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KYMCO Repair Manual Downtown 350i KYMCO Downtown 350i Service Manual Using this manual This manual has been designed to assist trained mechanics in servicing the models listed above. If you do not have the proper training or tools to perform a particular task it is best if you seek out a service professional.
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KYMCO Repair Manual Downtown 350i KYMCO reserves all rights to this publication and does not permit the reproduction or use of this publication, in full or in part, in any manner without our express written permission. No trademark or patent liability is assumed with respect to the use of the information contained in this manual.
KYMCO Repair Manual Downtown 350i 3.External Components This chapter covers the location and servicing of the external components for the KYMCO Downtown 350i model. REAR PART Seat ....................3-3 Luggage Box ..................3-7 Rear Carrier ..................3-9 Rear Center Cover ................3-10 Body Cover ..................3-11 Rear Inner Fender ................3-16...
KYMCO Repair Manual Downtown 350i 5.Cooling System This chapter covers the location and servicing of the cooling system components for the KYMCO Downtown 350i model. Coolant ....................5-3 Radiator ..................5-12 Water Temperature Sensor (WTS) ..........5-22 Water Pump ..................5-28 6.Fuel Injection System This chapter covers the location and servicing of the fuel system components for the KYMCO Downtown 350i model.
KYMCO Repair Manual Downtown 350i 8.Final Drive This chapter covers the location and servicing of the final drive components for the KYMCO Downtown 350i model. Final Drive Oil .................8-3 Final Reduction ................8-8 9.Electrical Systems This chapter covers the location and servicing of the electrical systems for the KYMCO Downtown 350i model.
KYMCO Repair Manual Downtown 350i 10.Brakes This chapter covers the location and servicing of the brake system components for the KYMCO Downtown 350i model. Brake Pad Replacement ..............10-2 Master Cylinders ................10-13 Master Cylinders ................10-22 Front Brake Caliper ................10-26 Rear Brake Caliper .................10-31 Brake Disc ..................10-37...
This chapter provides information on the rear suspension components of the KYMCO Downtown 350i model. Shock Absorbers ................13-2 Rear Fork ..................13-8 14.Wheels This chapter covers the location and servicing of the wheels for the KYMCO Downtown 350i model. Bearing Replacement ..............14-2 Front Wheel ..................14-6 Rear Wheel ..................14-11 Wheel Inspection ................14-19...
1.Quick Reference Downtown 350i 1. Quick Reference This chapter provides a quick reference source of technical specifications and information for KYMCO Downtown 350i models. Component Location ..............1-2 Special Tools ..................1-5 Specifications .................1-6 Torque Specifications ..............1-19 Troubleshooting ................1-22 VIN and Engine Number Location ..........1-27...
1.Quick Reference Downtown 350i KYMCO Downtown 350i Specifications General Information Downtown 350i (ACD5) Name (Model Code) Overall length (mm) 2250 Overall width (mm) Overall height (mm) 1310 Wheel base (mm) 1553 Engine type 4 stroke OHC Displacement (cc) Fuel recommended...
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1.Quick Reference Downtown 350i Starting system Starting motor Type Gasoline, 4-stroke Cylinder arrangement SINGLE CYLINDER Combustion chamber type Semi-sphere Valve arrangement O.H.C. Chain drive Bore x stroke (mm) 75.3 x 72 Compression ratio 10.7 Compression pressure 12 (kg/cm Max. Horsepower 30.05/7500 PS/rpm...
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1.Quick Reference Downtown 350i Air cleaner type & No Paper element, wet Fuel capacity 12.5 liter Brand Keihin Fuel System Type Throttle body Injection Venturi dia.(mm) Fuel pump pressure 3 Bar Type Ignition System Spec. CR7E (NGK) Electrical Equipment Spark plug Gap 0.6-0.7 mm...
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1.Quick Reference Downtown 350i ENGINE Throttle grip free play 2 ~ 6 mm Spark plug NGK: CR7E Spark plug gap 0.6 mm ~ 0.7 mm Valve clearance IN: 0.10 mm EX: 0.10 mm Idle speed 1600 ± 100 rpm Cylinder compression 12 ±...
1.Quick Reference Downtown 350i Fuel Injection System ITEM SPECIFICATIONS Throttle body identification number ACD5 Idle speed 1600 ± 100 rpm Throttle grip free play 2 - 6 mm (1/16 - 1/4 in) 9.9 - 13.5 Ω Fuel injector resistance (at 20°C/68°F) Float at full 1100 ±...
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1.Quick Reference Downtown 350i CELP FAILURE CODES LIST Failure Blinks Contents Causes Symptoms Codes • Faulty TPS voltage range (0.3 - 4.5 V) • Loose or poor connection on TPS Sensor Engine operates 06 P0120 Faulty TPS • Open or short circuit on the TPS wire normally •...
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1.Quick Reference Downtown 350i • Faulty Inductive ignition coil Ω range (4.2 Ω ± 15%) • Loose or poor connection on inductive ignition Faulty inductive Engine fails to be 37 P0351 coil ignition coil operated • Open or short circuit on inductive ignition coil wire •...
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1.Quick Reference Downtown 350i Axle/Brakes/Wheels Item Standard mm (in) Service Limit 0.2 mm — Axle shaft runout (0.008 in) 3.8 - 4.2 0.3 mm Brake disk thickness (front) (0.15 - 0.165) (0.012 in) — Brake disk thickness (rear) (0.2) —...
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1.Quick Reference Downtown 350i Electrical Item Standard Capacity 12V 10AH Fully charged 13.2V Battery Voltage (20°C) Insufficient charged < 12.3V Charging current 1.2A* 5 - 10H Item Standard Spark plug Standard type NGKCR7E Spark plug gap 0.6 - 0.7 mm 3.57 - 4.83 Ω...
1.Quick Reference Downtown 350i Troubleshooting Vehicle can not be started Preliminary 6 Step Inspection 1. Is the battery fully charged (12 V or higher). See the Battery topic for more information. 2. Key-On and listen for any action with Fuel Pump / Fuel Pump Relay (It will turn off automatically in 5-10 seconds) 3.
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1.Quick Reference Downtown 350i General Troubleshooting 1-23...
Your KYMCO dealer meets all of these requirements. * Should be serviced by your KYMCO dealer, unless you have the proper tools, service data and are technically qualified. ** In the interest of safety, we recommend these items be serviced only by your KYMCO dealer.
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2.Periodic Maintenance Downtown 350i WHICHEVER ODOMETER FREQUENCY COMES FIRST READING X 1000 km 1 5 10 15 20 25 30 X 1000 mi 0.6 3 6 9 12 15 18 ITEM MONTH 1 6 12 18 24 30 36 Air Filter Servicing...
2.Periodic Maintenance Downtown 350i Air Filter Servicing SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Replace the air filter according to the Maintenance Schedule, and more often in exceptionally rainy or dusty areas. Removal Remove the 8 air filter cover screws with a #2 Phillips screwdriver.
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2.Periodic Maintenance Downtown 350i Remove the 7 air filter bolts with an 8 mm socket or a #2 Phillips screwdriver. Remove the air filter from the airbox. Discard the air filter in favor of a new item. Caution: The air cleaner element has a viscous type paper element. Do not clean it with compressed air.
Downtown 350i Brake Fluid The KYMCO Downtown 350i uses DOT 4 brake fluid that should be inspected after 3,000 mi (5,000 km) of use. It should be flushed and bled every 12 months, 6,000 mi (10,000 km), whenever the brakes feel spongy, or if the brake system has been taken apart and rebuilt.
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2.Periodic Maintenance Downtown 350i Draining The brake bleeding process is the same for the front and rear brakes. Remove the two master cylinder cover screws with a #2 Phillips head screwdriver.
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2.Periodic Maintenance Downtown 350i Remove the cylinder cover. Remove the master cylinder cover, plastic piece and rubber diaphragm. Clean and inspect the rubber diaphragm for tears or other damage. Replace as necessary.
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2.Periodic Maintenance Downtown 350i Pull off the rubber cap over the bleeder valve and crack open the bleeder valve on the brake caliper using an 8 mm wrench. This valve is usually very tight so use a box end wrench or a 6 point socket and ratchet to prevent rounding off the head.
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2.Periodic Maintenance Downtown 350i Bleeding Place a length of 6 mm inside diameter clear hose on the bleeder valve and place the other end in a suitable container. A spare battery vent hose works well for this job. Fill the brake fluid with the proper type from a fresh, newly opened container.
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2.Periodic Maintenance Downtown 350i Pump the brake lever several times and hold the lever in. While holding the lever in, crack open the bleeder valve. The front brake lever will travel all the way to the grip and brake fluid and/or air will come out of the bleeder valve into the 6 mm hose.
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2.Periodic Maintenance Downtown 350i Place the rubber diaphragm, plastic piece and cover over the reservoir. Thread in the reservoir cover screws and tighten them securely with a #2 Phillips screwdriver. Check the function of the brakes before operating the machine.
2.Periodic Maintenance Downtown 350i Brake Inspection SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Brake Lever Adjuster There is adjuster on each brake lever. Each adjuster has four positions so that the released lever position can be adjusted to suit the rider’s hands.To adjust the distance of the lever from the handlebar grip, push the lever forward and turn the adjuster knob to align the number with the arrow mark on the lever holder.
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2.Periodic Maintenance Downtown 350i Brake Fluid Brake Pad Wear Replace the pads if the brake wear exceeds the wear indicator lines or if the wear is uneven. Note: Keep grease and oil off the brake discs to avoid brake failure.
2.Periodic Maintenance Downtown 350i Engine Compression Test SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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2.Periodic Maintenance Downtown 350i Low compression is an indication of excessive engine wear, possibly worn rings or poorly sealing valves, or maybe a tight valve with not enough valve clearance. High compression is possibly an indication of excessive carbon buildup on the piston or performance modifications.
2.Periodic Maintenance Downtown 350i Coolant Level Check SAFETY FIRST: Protective gloves and eyewear are recommended at this point. SAFETY FIRST: Antifreeze is highly toxic and can kill pets and animals if drank. Do not leave coolant where animals (including children!) can get to it.
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2.Periodic Maintenance Downtown 350i Remove the engine coolant lid screw with a #2 Phillips. And remove the engine coolant lid. Open the coolant reserve tank lid. Siphon the coolant out of the reserve tank with an appropriate suction device. If a suction device is unavailable remove the reserve tank and poor it out.
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2.Periodic Maintenance Downtown 350i Remove the engine coolant reserve tank cover. Open the coolant reserve tank lid. 2-19...
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2.Periodic Maintenance Downtown 350i Add coolant to the tank until it reaches the upper level mark. Note: Do not add coolant through the radiator cap. For more information on the engine coolant see the Coolant topic. 2-20...
2.Periodic Maintenance Downtown 350i Engine Oil SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Caution: Hot engine oil can burn. Avoid letting used motor oil contact exposed skin. TROUBLESHOOTING Oil level too low 1. Natural oil consumption 2.
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2.Periodic Maintenance Downtown 350i Oil Specifications Use a fully synthetic quality 4-stroke engine oil to ensure longer service life of the scooter. Only use oils that have a SJ rating above per the API service classification. Engine oil viscosity : SAE 5W-50 If these viscosities are not available, select an alternative engine oil according to the chart shown above.
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2.Periodic Maintenance Downtown 350i Inspection Oil Level Check the engine oil level each day before operating the scooter. Place the motorcycle upright on level ground for engine oil level check. Run the engine for 2 ~ 3 minutes and check the oil level after the engine is stopped for 2 ~ 3 minutes.
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2.Periodic Maintenance Downtown 350i Remove the oil filler cap/dipstick and wipe off the oil. Inspect the O-ring and replace it as needed. Insert the dipstick in without threading it in. Remove the dipstick and check the oil level. The level must be maintained between the upper (1) and lower level (2) marks on the oil filler cap/dipstick.
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2.Periodic Maintenance Downtown 350i If the oil level is at or below the lower mark add more of the same type and brand of oil to the engine through the oil filler hole. If the oil level is to high remove the drain plug and the excess oil.
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2.Periodic Maintenance Downtown 350i Servicing Draining Warm the engine as with the inspection, this will heat the engine and allow the oil to drain out faster and more completely. The vehicle should be on level ground. Stop the engine. Caution: Hot engine oil can burn. Avoid letting used motor oil contact exposed skin.
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2.Periodic Maintenance Downtown 350i Loosen the engine oil drain bolt with a 17 mm socket. Remove the bolt and allow the oil to drain into the pan. 2-27...
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2.Periodic Maintenance Downtown 350i Discard the old sealing washer. Remove the oil filler cap to allow for faster oil draining. Inspect the oil filler cap O-ring and replace it as needed. 2-28...
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2.Periodic Maintenance Downtown 350i When the oil has drained completely Install the drain bolt with a new sealing washer. Tighten the drain bolt to specification with a 17 mm socket. Torque Item Remarks kgf-m lb-ft Oil Drain bolt 18.08 New sealing washer Strainer Screen Remove the oil strainer screen bolt with a 17 mm socket.
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2.Periodic Maintenance Downtown 350i Remove the oil strainer screen. Remove the O-rings from the oil strainer screen and inspect them. Replace the O-rings if they are in poor condition. Inspect the oil strainer screen for debris and damage. Clean it with a high flash point solvent and compressed air. Metal debris in the strainer screen can be an indicator of engine wear or damage.
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2.Periodic Maintenance Downtown 350i Return the O-rings to the oil strainer screen and install it into the left side of the engine. Tighten the oil strainer screen cap to specification with a 17 mm socket. Torque Item kgf-m lb-ft Engine oil strainer cap 1.02...
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2.Periodic Maintenance Downtown 350i Loosen the oil filter cap with a 24 mm socket. Remove the oil filter cap with spring and take out the used oil filter. 2-32...
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2.Periodic Maintenance Downtown 350i Inspect the oil filter cap O-ring and spring. Replace the items if they are in poor condition. Install the spring to the oil filter cap. Apply a light coat of engine oil to the oil filter cap O-ring.
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2.Periodic Maintenance Downtown 350i Pour a small amount of fresh engine oil into the oil filter. Insert the oil filter into place with the rubber seal side facing up. Install the oil filter cap with spring. Makes sure the spring fits against the filter correctly.
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2.Periodic Maintenance Downtown 350i Filling Add the oil to the engine through the oil filler/dipstick hole. Use a fully synthetic quality 4-stroke engine oil to ensure longer service life of the scooter. Only use oils that have a SJ rating above per the API service classification.
2.Periodic Maintenance Downtown 350i General Lubrication SAFETY FIRST: Protective gloves and eyewear are recommended at this point. The frame lubrication points are listed below. Use general purpose grease. Apply clean engine oil or grease to cables and movable parts not specified. This will avoid abnormal noise and increase the durability of the motorcycle.
2.Periodic Maintenance Downtown 350i Hose Inspection Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Inspect the breather hose for damage and deterioration. Inspect the fuel hose for damage and deterioration.
2.Periodic Maintenance Downtown 350i Side Stand SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Interlock Function Check Your scooter's side stand is not only necessary when you park, but it contains an important safety feature. This feature cuts-off the ignition if you try to ride the scooter when the side stand is down.
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2. Put the side stand up and start the engine. 3. Lower the side stand. 4. The engine should stop as you put the side stand down. Note: If the side stand system does not operate as described, see your KYMCO dealer for service. 2-39...
2.Periodic Maintenance Downtown 350i Spark Plug SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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2.Periodic Maintenance Downtown 350i Remove the spark plug with a spark plug with a 5/8 in socket. Spark plug NGKCR7E Inspection Always check the gap of the spark plug before installation. If the gap needs to be adjusted bend the ground electrode carefully. Inspect the color of the porcelain nose of the spark plug.
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2.Periodic Maintenance Downtown 350i Installation Thread the spark plug by hand before using a socket to tighten. Torque to specification with a 5/8" spark plug socket. Do not over tighten the spark plug. The cylinder head is made out of soft metal, and it can be easily damaged.
2.Periodic Maintenance Downtown 350i Steering SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Inspection Raise the front wheel off the ground and check that the steering handlebar rotates freely. If the handlebar moves unevenly, binds, or has vertical movement, adjust the steering head bearing.
2.Periodic Maintenance Downtown 350i Suspension SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Front Suspension Check the action of the front shock absorbers by compressing them several times. Check the entire shock absorber assembly for oil leaks, looseness or damage.
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2.Periodic Maintenance Downtown 350i Pre-Load Setting Each shock absorber on the scooter has 5 spring preload adjustment positions for different load or riding conditions. Position 1 is for light loads and smooth road conditions. Position 3 to 5 increase spring preload for stiffer rear suspension and can be used when the scooters heavily loaded.
2.Periodic Maintenance Downtown 350i Throttle Free Play SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Inspection Closed Resistance First Felt Check the throttle cable free play by gently rotating the throttle grip back until resistance is felt.
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2.Periodic Maintenance Downtown 350i Major adjustment Major adjustment of the throttle grip free play is made with the adjusting nut at the throttle body side. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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2.Periodic Maintenance Downtown 350i The top throttle cable is the opening cable and the bottom is the closing cable. Loosen the lock nut (forward) with a 12 mm wrench. 2-48...
2.Periodic Maintenance Downtown 350i Turn the adjuster nut (rear) to adjust the throttle free play. When the free play has been moved into specification hold the adjuster in place and tighten the locknut securely. Adjust the closing cable as needed for a proper throttle action.
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2.Periodic Maintenance Downtown 350i Slide down the rubber cover. Loosen the throttle cable adjuster lock nut with a 10 mm wrench. 2-50...
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2.Periodic Maintenance Downtown 350i Turn the adjuster with an 8 mm wrench to achieve the specified free play. When the free play has been moved into specification hold the adjuster in place and tighten the locknut securely. Slide the rubber cover over the adjuster and lock nut.
2.Periodic Maintenance Downtown 350i Tires SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Check tires before each ride for wear and air pressure. Check tire air pressure before riding when tires are cold. 2.00 kg/cm Front (28.4 psi) Solo riding 2.25 kg/cm...
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2.Periodic Maintenance Downtown 350i Replace tires if the tread depth reaches the wear mark or fails to meet the minimum tread depth. Front wheel 120/80-14 58S Tires Rear wheel 150/70-13 64S 2-53...
2.Periodic Maintenance Downtown 350i Final Drive Oil SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Place the scooter on level ground and up on its center stand. The oil drain bolt and oil filler bolt are located on the transmission.
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2.Periodic Maintenance Downtown 350i Draining Place the vehicle on its center stand on level ground. Place a suitable oil drain pan under the transmission oil drain plug. Remove the transmission oil level filler bolt with a 12 mm socket. 2-55...
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2.Periodic Maintenance Downtown 350i Place a suitable container under the drain plug to capture the final drive oil. Loosen the oil drain plug with a 12 mm socket. Remove the drain plug and slowly rotate the rear wheel to drain the transmission oil.
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2.Periodic Maintenance Downtown 350i Install the oil drain plug and washer with a 12 mm socket. Tighten to specification. Torque Thread Item size (mm) kgf-m lb-ft Final drive oil drain bolt 0.8 - 1.2 5.79 - 8.68 2-57...
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2.Periodic Maintenance Downtown 350i Filling Fill the final drive with the specified quantity of oil with a syringe. Gear oil type: SAE 90 Gear oil capacity: At disassembly 0.23 Liter At change 0.21 Liter 2-58...
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2.Periodic Maintenance Downtown 350i Thread in the final drive oil level filler bolt. Install the oil filler plug and torque it to specification with a 12 mm socket. Torque Thread Item size (mm) kgf-m lb-ft Final drive oil filler bolt 0.8 - 1.2...
2.Periodic Maintenance Downtown 350i Valve Clearance SAFETY FIRST: Protective gloves and eyewear are recommended at this point. The valve clearance specification is only relevant if the engine is cold (below 35°C or 95°F). Inspection Remove the seat. See the Seat topic for more information.
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2.Periodic Maintenance Downtown 350i Remove the timing inspection cap from the right side of the engine with a large flat blade screwdriver. Inspect the O-ring on the cap and replace it as needed. The crankshaft must be rotated (clockwise) until the piston is at top dead center (TDC) on the compression stroke.
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2.Periodic Maintenance Downtown 350i Turn crankshaft clockwise until the "T" mark aligns with the index notch in the timing inspection hole. For correct engine timing the marks on the camshaft sprocket must be even with the cylinder head mating surface at the same time the "T" mark is lined up with the with the index notch in the timing inspection hole.
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2.Periodic Maintenance Downtown 350i Measure the valve clearance with a thickness feeler gauge. Insert the feeler gauge between the tappet adjusting screw and the valve stem. The clearance is correct when there is a light drag on the feeler gauge. The clearance is the same for the exhaust and intake valves.
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2.Periodic Maintenance Downtown 350i Adjustment Use a tappet adjuster tool to adjust the valves. SPECIAL TOOLS ITEM TOOL NO. DESCRIPTION TAPPET ADJUSTER E012 Tappet adjustment 2-64...
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2.Periodic Maintenance Downtown 350i Place a 9 mm box end wrench over the locknut, and loosen the locknut. If the valve clearance is tight back out the valve tappet adjusting screw with the tappet adjustment tool. If the clearance is too loose turn in the adjusting screw until there is a light drag on the feeler gauge.
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2.Periodic Maintenance Downtown 350i Make sure the O-rings on the crankshaft and timing plugs are in good condition. Replace them as needed. Install the timing inspection and crankshaft caps to the right side of the engine. Tighten the caps securely but not overly with a large flat blade screwdriver.
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3.External Components Downtown 350i 3.External Components This chapter covers the location and servicing of the external components for the KYMCO Downtown 350i model. REAR PART Seat ....................3-3 Luggage Box ..................3-7 Rear Carrier ..................3-9 Rear Center Cover ................3-10 Body Cover ..................3-11 Rear Inner Fender ................3-16...
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3.External Components Downtown 350i FRONT PART Front Center Cover ................3-29 Front Cover ..................3-30 Windshield ..................3-31 Front Meter Cover ................3-32 Head Light Assembly ..............3-33 Key Cover ..................3-36 Dash Board ..................3-38 Side Covers And Skirts ..............3-40 Side Board A ..................3-43 Side Board B ..................3-45 Floor Panel ..................3-47...
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3.External Components Downtown 350i General Instructions • When removing frame covers, use care not to pull them by force because the cover joint claws may be damaged. • Make sure to route cables and harnesses according to the Cable & Harness...
3.External Components Downtown 350i REAR PART Seat SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Insert the key and turn it counterclockwise . Lift up the seat.
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3.External Components Downtown 350i Remove the two piston pivot nuts with a 10 mm socket. Lift off the piston pivot mounting plate.
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3.External Components Downtown 350i Remove the two seat hinge nuts with a 10 mm socket. Remove the seat.
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3.External Components Downtown 350i Seat Latch Cable The seat latch cable runs from the ignition switch to the seat latches. The cable must be adjusted periodically so that the latches will open correctly. Open the seat.
3.External Components Downtown 350i Luggage Box SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the two luggage bolts and nuts.
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3.External Components Downtown 350i Remove the PDA panel located at the rear of the luggage box and free the PDA plug. Lift up the luggage box to unplug the luggage box light connector. Remove the luggage box.
3.External Components Downtown 350i Rear Carrier Removal SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Pry off the carrier bolt covers with a small flat blade screwdriver, the arrow mark indicates the pry point. Remove the four carrier bolts with a 6 mm Allen.
3.External Components Downtown 350i Rear Center Cover Removal SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
3.External Components Downtown 350i Body Cover SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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3.External Components Downtown 350i Remove the upper body cover bolt with a 10 mm socket. Remove the two mounting nuts. Remove the fasteners. 3-13...
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3.External Components Downtown 350i Unplug the taillight connector. Unplug the tag light connector. Remove the body cover. 3-14...
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3.External Components Downtown 350i Disassembly Taillight Assembly Remove the taillight assembly screws with a #2 Phillips. Unplug the connector of the license light. Remove the screws. 3-15...
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3.External Components Downtown 350i Separate the mud flap and the taillight assembly. Remove the license light assembly. 3-16...
3.External Components Downtown 350i Rear Inner Fender Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Remove the rear carrier. See the Rear Carrier topic for more information.
3.External Components Downtown 350i Rear Tire Fender Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Remove the rear carrier. See the Rear Carrier topic for more information.
3.External Components Downtown 350i Heat Shield Removal Remove the seat. See Remove the two rear center cover screws with a #2 Phillips. Carefully unhook the tabs on both sides and remove the rear center cover. Heat Shields Remove the muffler heat shield bolts with a 10 mm socket.
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3.External Components Downtown 350i To remove the heat shield on the exhaust pipe remove the two bolts with an 8 mm socket. 3-20...
3.External Components Downtown 350i Exhaust System SAFETY FIRST: Protective gloves and eyewear are recommended at this point. General Instructions • When removing frame covers, use care not to pull them by force because the cover joint claws may be damaged.
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3.External Components Downtown 350i Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Remove the rear carrier. See the Rear Carrier topic for more information. Remove the body cover. See the Body Cover topic for more information.
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3.External Components Downtown 350i Remove the three muffler mounting bolts with a 14 mm socket. And remove the exhaust system. Remove the exhaust pipe gasket and discard it. 3-23...
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3.External Components Downtown 350i Sensor Removal Remove the O sensor with a 17 mm wrench. Use care not to pinch the wires. The O sensor issues signal to ECU when the temperature is over 350°C while the engine is running.
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3.External Components Downtown 350i Exhaust System Installation Insert a new exhaust pipe gasket into the exhaust port. Fit the exhaust system into place 3-25...
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3.External Components Downtown 350i Install the two exhaust pipe joint nuts with a 12 mm deep well socket. Do not tighten. Install the three muffler mounting bolts and tighten to specification with a socket. Torque Item kgf-m Muffler Mounting Bolts...
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3.External Components Downtown 350i Tighten the two exhaust pipe joint nuts to specification with a 12 mm deep well socket. Torque Item kgf-m Exhaust Pipe Joint Nuts If the exhaust pipe and muffler were separated tighten the muffler clamp securely.
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3.External Components Downtown 350i Installation Sensor Apply anti-seize compound to the threads of the O sensor. Install the O sensor and tighten it to specification with a 17 mm wrench. Use care not to pinch the wires. Torque Item lb-ft...
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3.External Components Downtown 350i FRONT PART Follow the dismantled order as below illustration. 3-29...
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3.External Components Downtown 350i Front Center Cover Removal Pull the front center cover with certain direction. Remove the front center cover. 3-30...
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3.External Components Downtown 350i Front Cover Removal Remove the fastener. Remove the screws. And remove the front cover. 3-31...
3.External Components Downtown 350i Windshield Removal Remove the 4 hex mounting bolts. Rotate the KYMCO logo plate. Remove the screw. And remove the windshield. 3-32...
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3.External Components Downtown 350i Front Meter Cover Removal Remove the front meter cover. 3-33...
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3.External Components Downtown 350i Head Light Assembly Removal Remove the head light assembly and side moldings as a set. Remove the two mounting nuts. Push fender down to loosen the tabs. 3-34...
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3.External Components Downtown 350i Use pry tool to release the tabs. Note: Be carefully not to damage the tabs and surfaces of the board. Unplug the coupler of headlight. 3-35...
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3.External Components Downtown 350i Remove the head light assembly. 3-36...
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3.External Components Downtown 350i Key Cover Removal Remove the front cover, windshield and meter cover first. Loosen the mounting screw then turn and remove the ignition cover. 3-37...
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3.External Components Downtown 350i Remove the left and right fasteners. 3-38...
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3.External Components Downtown 350i Dash Board Removal Remove the dash board and cover as a set. Remove the left and right bolts. 3-39...
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3.External Components Downtown 350i Remove the couplers. Remove the dash board set. 3-40...
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3.External Components Downtown 350i Side Covers And Skirts Removal Remove the floor mat. Remove the side cover, turn signal light and skirt as a set. 3-41...
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3.External Components Downtown 350i Remove the screws which are mounted on floor panels. Remove the screws. Remove the screws. 3-42...
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3.External Components Downtown 350i Remove the fasteners. Remove the skirt set. 3-43...
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3.External Components Downtown 350i Side Board A Removal Note: 90652-LCA4 fasteners are mounted with body cover. Remove the mounting bolts of side board A. 3-44...
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3.External Components Downtown 350i Use tool to pry the tabs. Be carefully not to damage the tabs and surfaces of the board. Remove both the right and left side board A. 3-45...
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3.External Components Downtown 350i Side Board B Removal 3-46...
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3.External Components Downtown 350i Remove the mounting bolts of side board B. Remove the right and left side board B. 3-47...
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3.External Components Downtown 350i Remove the bolts and screws. Remove the right and left floor panels. 3-49...
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3.External Components Downtown 350i Leg Shield Set Removal Use ignition key and remove the fueling cap. 3-50...
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3.External Components Downtown 350i Remove the left and right bolts. Remove the coupler. Remove the leg shield set. 3-51...
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3.External Components Downtown 350i Inner Fender Removal Remove the connecter of the air temperature sensor. 3-52...
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3.External Components Downtown 350i Remove the left and right fasteners and remove front inner fender. Remove the screw. Remove the rear inner fender set. 3-53...
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3.External Components Downtown 350i Under Cover Set Removal Remove the connecter of the air temperature sensor. 3-54...
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3.External Components Downtown 350i Remove the left and right fasteners and remove front inner fender. Remove the screw. Remove the rear inner fender set. 3-55...
3.External Components Downtown 350i Front Fender SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal The front fender is held in place with four bolts, two on each side. Remove the left forward front fender bolt with a 6 mm Allen.
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3.External Components Downtown 350i Remove the right forward front fender bolt with a 6 mm Allen. And remove the right rear fender bolt with a 10 mm socket. Remove the front fender from the forks. 3-57...
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3.External Components Downtown 350i Handlebar SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the handlebar covers. See the Handlebar Covers topic for more information. Remove the front cover. See the Front Cover topic for more information.
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3.External Components Downtown 350i Switch Housings and Throttle Remove the two right switch housing mounting screws with a #2 Phillips screwdriver. Disconnect the switch. Separate the switch housing from the handlebar. Disconnect the throttle cables and free the right switch housing from the handlebar.
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3.External Components Downtown 350i Slide off the throttle grip. Remove the two left switch housing mounting screws with a #2 Phillips screwdriver. Disconnect the switch. Separate the left switch housing from the handlebar. 3-60...
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3.External Components Downtown 350i Handlebar Route the cables and lines from the handlebar cable guide. Hold the handlebar lock bolt with a 14 mm wrench and loosen the nut with a 17 mm socket. Installation torque: Torque Item lb-ft Handlebar Lock Nut...
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3.External Components Downtown 350i Remove the handlebar lock nut and bolt. Remove the handlebar. 3-62...
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3.External Components Downtown 350i Grips If you plan to replace the grips you can slice them lengthwise with a razor blade and peel them off. To remove the grips without cutting them use a screwdriver to open a gap between the grip and the handlebar. Spray in contact cleaner to break up the grip cement.
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3.External Components Downtown 350i When installation: Switch Housings and Throttle Align the left switch housing and install on the handlebar. Insert the two housing screws and tighten them securely with a #2 Phillips screwdriver. Connect the switch. Slide the throttle grip onto the right side of the handlebar.
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3.External Components Downtown 350i Install the right switch and throttle housing. The post on the housing should fit into the hole in the bar. Lubricate the end of the throttle in grease. Fit the ends of the throttle cables into the throttle tube.
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3.External Components Downtown 350i Bar Ends Install the bar ends with a 6 mm Allen. Install the front cover. See the Front Cover topic for more information. Install the handlebar covers. See the Handlebar Covers topic for more information. Check the throttle free play. See the...
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3.External Components Downtown 350i Removal Upper Cover Remove the four cover screws with a #2 Phillips. Lift up the rubber cover and loosen the mirror with a 17 mm wrench. Remove both mirrors in the same manner. 3-68...
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3.External Components Downtown 350i Carefully free the tabs and remove the upper handlebar cover. Lower Cover Remove the luggage box. See the Seat topic for more information. Remove the throttle cables from the throttle body. See the Throttle Body Removal and Installation topic for more information.
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3.External Components Downtown 350i Remove the four cover bolts and screws. Remove the lower cover. 3-70...
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3.External Components Downtown 350i Stands Side stand Removal Remove the luggage box. See the Luggage Box topic for more information. Remove the foot skirt. Unplug the three-pin side stand switch connector. 3-71...
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3.External Components Downtown 350i Remove the side stand spring with a spring puller. Remove the side stand bolt, switch, and side stand. 3-72...
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3.External Components Downtown 350i Center Stand Removal Remove the center stand spring with a spring puller. Remove the two center stand nuts and bolts. Remove the center stand. 3-73...
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4.Engine Downtown 350i 4.Engine This chapter covers the location and servicing of the engine components for the KYMCO Downtown 350i model. Cylinder Head Cover ..............4-5 Camshaft ..................4-8 Cylinder Head .................4-23 Valves ....................4-31 Cylinder and Piston ...............4-37 Starter Clutch .................4-62 Generator ..................4-69 Oil Pump ..................4-73...
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4.Engine Downtown 350i TROUBLESHOOTING Oil level too low 1. Natural oil consumption 2. Oil leaks 3. Worn or poorly installed piston rings 4. Worn valve guide or seal Poor lubrication pressure 1. Oil level too low 2. Clogged filter or oil passages 3.
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4.Engine Downtown 350i TROUBLESHOOTING • The poor cylinder head operation can be diagnosed by a compression test or by tracing engine top-end noises. Poor performance at idle speed • Compression too low Compression too low • Incorrect valve clearance adjustment •...
4.Engine Downtown 350i White smoke from exhaust muffler • Worn valve stem or valve guide • Damaged valve stem oil seal Cylinder and Piston • The cylinder and piston cannot be serviced with the engine installed in the frame. • After disassembly, clean the removed parts and dry them with compressed air before inspection.
4.Engine Downtown 350i Cylinder Head Cover SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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4.Engine Downtown 350i Loosen the fuel hose stay bolt with an 8 mm socket. Free the fuel hose stay from the cylinder head cover. Loosen the four cylinder head cover bolts with a 10 mm socket. Remove the cylinder head cover bolts with washers and grommets. Note the gold colored and...
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4.Engine Downtown 350i Remove the cylinder head cover and gasket. Discard the gasket and replace it with a new item on installation. Remove the dowel pin.
4.Engine Downtown 350i Camshaft SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Remove the spark plug. See the Spark Plug topic for more information.
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4.Engine Downtown 350i Remove the cam chain tensioner cap bolt with a 10 mm socket. Loosen the cam chain tensioner mounting bolts evenly with an 8 mm socket. Lift the cam chain tensioner our of the cylinder. Remove the cam chain tensioner...
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4.Engine Downtown 350i Use a 5 mm Allen wrench to remove the camshaft sprocket bolts. Remove the camshaft sprocket as shown. Support the chain so it does not fall into the cylinder head. Use a 5 mm Allen wrench to remove the set plate bolt.
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4.Engine Downtown 350i Remove the set plate as shown. Thread a bolt into the rocker arm shafts and pull the shafts out. Lift out the rocker arms as the shafts are removed. 4-11...
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4.Engine Downtown 350i Remove the camshaft from the cylinder head. 4-12...
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4.Engine Downtown 350i Inspection Inspect the camshaft cam heights for the intake and exhaust lobes. Inspect the camshaft bearings for excessive play or roughness. Replace the entire camshaft assembly if the bearings are rough or have excessive play. Item Standard (mm) 34.2987...
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4.Engine Downtown 350i Inspect the rocker arm inner diameter for the intake and exhaust valves. Item Standard (mm) 10.00 - 10.015 Valve rocker arm I.D. 10.00 - 10.015 Inspect the camshaft bearing journals for scoring or scratches. 4-14...
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4.Engine Downtown 350i Inspect the camshaft sprocket for worn teeth or other signs of wear or damage. Camshaft Installation Clear out the cylinder head oil passages with compressed air. Make sure all cylinder head oil passages are free of clogs.
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4.Engine Downtown 350i Remove the timing inspection cap from the right side of the engine with a large flat blade screwdriver. Inspect the O-ring on the cap and replace it as needed. The crankshaft must be rotate (clockwise) until the piston is at top dead center (TDC) on the compression stroke.
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4.Engine Downtown 350i Insert the camshaft into the camshaft holders with the lobes facing down. Lubricate the inside diameter of the rocker arms and the roller with fresh engine oil. Position the rocker arms to accept the rocker arm shafts.
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4.Engine Downtown 350i Install the camshaft set plate so it fits into the groove on the camshaft and between the projections on the rocker arm shafts. Apply a small amount of blue Loctite (non-permanent) to the threads of the set plate bolt.
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4.Engine Downtown 350i Install the camshaft sprocket onto the camshaft so the camshaft sprocket boss fits into the appropriate hole on the camshaft sprocket. Make sure the camshaft sprocket boss is facing up so it is visible above the edge of the cylinder head as shown.
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4.Engine Downtown 350i Double check the engine timing. Use a small flat blade screwdriver bring in the cam chain tensioner rod. Turn the screwdriver counter clockwise to retract the rod. The rod must be held in with the screwdriver until the cam chain tensioner mounting bolts have been installed.
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4.Engine Downtown 350i Rotate the crankshaft 360° clockwise and check the engine timing one more time. Make sure the cam chain tensioner cap bolt O-ring is in good condition. Install the O-ring and cam chain tensioner cap bolt. Tighten the bolt to securely with a 10 mm socket.
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4.Engine Downtown 350i Check the valve clearance. See the Valve Clearance topic for more information. Make sure the O-rings on the crankshaft and timing plugs are in good condition. Replace them as needed. Install the timing inspection and crankshaft caps to the right side of the engine.
4.Engine Downtown 350i Cylinder Head SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the spark plug. See the Spark Plug topic for more information. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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4.Engine Downtown 350i Loosen the thermostat hose clamp with a #2 Phillips screwdriver. Slide up the clamp and free the coolant hose from the thermostat. Allow any remaining coolant to drain into a suitable container. Squeeze the air bleed hose clamp with needle nose pliers and slide back the clamp.
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4.Engine Downtown 350i Remove the two right side cylinder head bolts with an 8 mm socket. Also, loosen the two cylinder bolts below with an 8 mm socket. There are two cylinder head mounting nuts; one below the intake port and one below the exhaust port.
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4.Engine Downtown 350i Loosen the upper nut with a 10 mm socket and the lower nut with a 10 mm wrench. Remove the two cylinder head mounting nuts. Remove the four camshaft holder nuts using a 14 mm socket. Loosen the camshaft holder nuts in a criss cross pattern over the course of 2-3 loosening sequences.
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4.Engine Downtown 350i Lift the cylinder head off of the studs. Guide the cam chain through the opening in the cylinder head but do not allow the chain to fall into the crankcase. Remove the cylinder head gasket. Remove the two dowel pins from the left side cylinder head studs.
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4.Engine Downtown 350i Remove the two intake mounting nuts with a 10 mm socket. Remove the intake from the cylinder head. Inspect the intake O-ring and replace it as needed. 4-28...
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4.Engine Downtown 350i Remove the intake plate and gasket from the cylinder head. Use a 17 mm wrench to remove the water temperature sensor if needed. Clean the combustion chamber with contact cleaner, a plastic knife, brush and/or rag. Take care to only remove carbon and not scrape the head.
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4.Engine Downtown 350i Place a straight edge across the bottom of the cylinder head and check for warp with a feeler gauge. You will need to check clearance readings from several places on the bottom of the cylinder head surface for warp.
4.Engine Downtown 350i Valves SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the camshaft. See the Camshaft topic for more information. Remove the cylinder head. See the Cylinder Head topic for more information. IMPORTANT: Record the position of all parts so they can be returned to their proper place during reassembly.
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4.Engine Downtown 350i Remove the spring retainer. Remove the valve springs. Push the valve stem down and remove the valve from the combustion chamber side of the cylinder head. Rotate the valve as it is removed. 4-32...
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4.Engine Downtown 350i Remove the valve seal from the valve guide. The valve seals should be replaced if they are removed or you are going to install new valves. Remove the spring seat. 4-33...
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4.Engine Downtown 350i Inspection Inspect the valve springs for fatigue and damage. Replace the valve springs as needed or if the valve is also to be replaced. 4-34...
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4.Engine Downtown 350i Inspect the valves for damage and burning. Measure the valve stem diameter in several places where the valve makes contact with the guide. If the measurement is below specification replace the valve. Item Standard (mm) 4.990 - 4.975 Valve stem O.D.
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4.Engine Downtown 350i Measure the inside diameter of the valve guides. Replace the guides if the measurement is out of specification. Calculate the valve stem-to-guide clearance. Replace the guide and valve if the clearance is out of specification. Item Standard (mm) 5.00 - 5.012...
4.Engine Downtown 350i Cylinder and Piston SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Cylinder Block Removal Remove the engine from the frame. See the Engine Removal topic for more information. Remove the cylinder head cover. See the...
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4.Engine Downtown 350i Loosen the cylinder coolant hose clamp with a #2 Phillips screwdriver. Free the coolant hose from the cylinder. Slide the cylinder off of the studs and piston. Guide the cam chain through its opening and do not allow if to fall into the crankcase. Remove the cylinder.
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4.Engine Downtown 350i Remove the two cylinder dowel pins from the left studs. Place a clean shop towel under and around the base of the piston to prevent any parts or debris falling into the crankcase. Remove the piston pin clips with a pick or needle nose pliers. Discard the piston pin clips.
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4.Engine Downtown 350i Spread the piston rings and lift them off opposite the gap. Spread the rings the minimum amount during removal. The rings can be easily damaged. The two upper rings are each a single piece of metal. The oil ring consists of an expander ring and two side rails.
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4.Engine Downtown 350i Clean the carbon build up off of the piston with a stiff bristled plastic brush or rag. Never use a wire brush to clean a piston. Also clean out the ring grooves. You can use an old ring to scrape out any carbon build up in the grooves.
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4.Engine Downtown 350i Inspection The cylinder and piston must be replaced as a set. There are two sets of cylinder and piston combinations. Make sure to have a No.A cylinder with an "A" piston or a No.B cylinder with a "B" piston.
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4.Engine Downtown 350i Measure the cylinder diameter as described below with a telescoping gauge. Inspect the cylinder front to back and side to side at three different height levels with a dial bore gauge. Replace the cylinder and piston as a set if the cylinder is out of specification.
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4.Engine Downtown 350i Measure the outside diameter of the piston at 9 mm up from the bottom of the skirt at a 90° angle to the piston pin. Measure the piston with vernier calipers or a micrometer. Check the piston for wear, damage, and extreme discoloration.
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4.Engine Downtown 350i Measure the inside diameter of the small end of the connecting rod with vernier calipers. Item Standard (mm) Connecting rod small end I.D. Bore 15.016 - 15.034 Measure the ring groove width and the ring-to-groove clearance with feeler gauges.
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4.Engine Downtown 350i Insert the top ring into the cylinder. Push the top ring in the cylinder about an inch. Use the piston to push in the ring to keep it square with the cylinder. Measure the ring gap with a feeler gauge. Repeat this procedure with second ring and the oil side rails.
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4.Engine Downtown 350i Check the oil jet for clogs. 4-47...
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4.Engine Downtown 350i Assembly Clean the piston ring grooves and apply fresh engine oil to the piston rings. Spread the rings the minimum amount possible to install them. Do not try and force them on the piston. Install the top and second rings with their markings facing up. Install the rings to the piston as shown above so that no ring end gaps line up with the piston pin or perpendicular to the piston pin.
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4.Engine Downtown 350i Install the oil expander ring so that the ends are not overlapping. Install the steel rails above and below the oil ring. Lubricate the piston pin and the small end of the connecting rod with fresh engine oil.
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4.Engine Downtown 350i The "IN" mark should face the intake side (rear) of the engine. Place the piston over the connecting rod. Insert the piston pin into the piston and rod. Install new piston pin clips securely into their grooves. Turn the gap in the clips away from the access gap.
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4.Engine Downtown 350i Make sure the cylinder head mating surface is clean. Install the two dowel pins as shown. Install the new base gasket onto the crankcase. Coat the inside of the cylinder, piston rings, and piston in fresh engine oil. Lower the cylinder over the studs and guide the piston into the cylinder while you are compressing the rings with your fingers.
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4.Engine Downtown 350i Thread in the two cylinder bolts on the right side of the engine. Fit the coolant hose to the cylinder. Tighten the cylinder coolant hose clamp to securely with a #2 Phillips screwdriver. Insert the lower cam chain guide and make sure it is seated correctly.
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4.Engine Downtown 350i A.C. Generator and Starter clutch SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Drain engine oil and remove the oil filter. See the Engine Oil topic for more information. Drain the coolant. See the Coolant topic for more information.
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4.Engine Downtown 350i Loosen the water pump hose clamp with a #2 Phillips screwdriver. Slide up the clamp and free the coolant hose from the water pump. Allow any remaining coolant to drain into a suitable container. Loosen the right crankcase coolant hose clamp with a #2 Phillips screwdriver.
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4.Engine Downtown 350i Remove the 12 generator cover bolts with an 8 mm socket. Utilize the pry points and remove the generator cover. Remove the generator cover gasket. 4-55...
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4.Engine Downtown 350i Remove the two dowel pins. Remove the two oil filter chamber O-rings. Inspect the O-rings and replace them as needed. 4-56...
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4.Engine Downtown 350i Stator and Pulsar Coil/Crank Position Sensor To inspect the stator see the Charging System topic. For crank position sensor inspection see the Ignition System topic. Free the rubber wire grommet from the right crankcase cover. Remove the three stator mounting bolts and the two crank position sensor bolts with an 8 mm socket.
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4.Engine Downtown 350i Flywheel To remove the fly wheel two special tools are needed. ITEM TOOL NO. UNIVERSAL HOLDER E021 ITEM TOOL NO. FLYWHEEL PULLER E003 4-58...
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4.Engine Downtown 350i Hold the flywheel with the universal holder and loosen the nut with a 19 mm socket. Remove the flywheel nut and washer. 4-59...
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4.Engine Downtown 350i Apply grease to the threads of the flywheel puller tool before using it. Thread the puller onto the flywheel. Hold the tool with a large wrench and turn in the bolt until the pressure separates the flywheel from the crankshaft.
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4.Engine Downtown 350i Slide the starter driven gear off of the crankshaft. Remove the woodruff key from the crankshaft. 4-61...
4.Engine Downtown 350i Starter Clutch Remove the starter idle gear and shaft from the crankcase. Inspect the starter idle gear and shaft for wear and damage. Replace the idle gear and shaft as needed. Inspect the starter driven gear for wear and damage. Measure the inside and outside diameter of the starter driven gear and replace it as needed.
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4.Engine Downtown 350i Fit the boss of the starter driven gear into the starter clutch. The starter clutch should only allow the driven gear to turn in one direction. If the starter clutch allows turning both ways or will not let the driven gear rotate smoothly in one direction the starter clutch must be replaced.
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4.Engine Downtown 350i Installation Starter Clutch Fit the starter clutch to the back of the flywheel. Apply blue Loctite to the threads of the three starter clutch mounting bolts. Insert the three starter clutch mounting bolts. Tighten the starter clutch mounting bolts to specification with a 6 mm Allen socket.
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4.Engine Downtown 350i Lubricate the starter idle gear shaft with fresh engine oil. Install the starter idle gear and shaft into the crankcase. Flywheel Install the woodruff key into its slot on the end of the crankshaft. 4-65...
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4.Engine Downtown 350i Lubricate the inside of the starter driven gear with fresh engine oil. Slide the starter driven gear onto the flywheel as shown. Clean off the tapered end of the crankshaft where the flywheel will ride and make sure the inside of the flywheel is oil free where it will contact the crankshaft.
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4.Engine Downtown 350i Install the washer and flywheel nut. Hold the flywheel with the universal holder and torque the flywheel nut to specification with a 19 mm socket. Torque Thread Item size (mm) kgf-m lb-ft ACG flywheel nut 5.5-6.5 39.78-47.01 ITEM TOOL NO.
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4.Engine Downtown 350i Stator and Crank Position Sensor Fit the stator and the crankshaft position sensor into the generator cover together as shown. Insert the two crank position sensor mounting bolts and the three stator mounting bolts. Tighten the bolts securely with an 8 mm socket.
4.Engine Downtown 350i Generator Cover Make sure the generator cover mating surface is clean. Install the two dowel pins and a new generator cover gasket. Make sure the oil filter chamber O-rings are in place and in good condition. 4-69...
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4.Engine Downtown 350i Fit the generator cover into place. Make sure the water pump shaft engages correctly with the oil pump shaft. Insert the 12 generator cover bolts. Tighten the bolts securely in a with an 8 mm socket. 4-70...
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4.Engine Downtown 350i Fit the coolant hose to the right crankcase cover pipe. Secure the hose with the clamp and tighten the coolant hose clamp securely with a #2 Phillips screwdriver. Connect the coolant hose to the water pump. Move the clamp into place and tighten it securely with a #2 Phillips screwdriver.
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4.Engine Downtown 350i Plug in the regulator/rectifier 3-pin connector. Plug in the crank position sensor wire coupler on the right side of the frame. Fill the engine oil. See the Engine Oil topic for more information. Install the exhaust system. See the Exhaust System topic for more information.
4.Engine Downtown 350i Oil Pump SAFETY FIRST: Protective gloves and eyewear are recommended at this point. GENERAL INSTRUCTIONS The maintenance of lubrication system can be performed with the engine installed in the frame. Use care when removing and installing the oil pump not to allow dust and foreign matters to enter the engine and oil line.
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4.Engine Downtown 350i Oil Pump Removal Drain the engine oil. See the Engine Oil topic for more information. Remove the generator cover, flywheel, starter idle gear and starter driven gear. See the A.C. Generator and Starter clutch topic. The oil pump is driven by a chain off of the crankshaft.
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4.Engine Downtown 350i Remove the two oil pump cover bolts and the oil pump cover. Remove the snap ring on the oil pump shaft with snap ring pliers. Remove the oil pump drive chain and driven sprocket. Inspect the oil pump drive chain and sprocket for signs of wear and damage.
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4.Engine Downtown 350i Remove the two oil pump screws with an impact #3 Phillips screwdriver. Remove the filter. Remove the oil pump. Turn the oil pump shaft by hand and make sure it turns smoothly. If the oil pump shaft will not rotate smoothly the oil pump should be replaced with a new unit.
4.Engine Downtown 350i Crankcase SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Splitting Drain the engine oil and remove the strainer screen. See the Engine Oiltopic for more information. Remove the engine. See the Engine Removal topic for more information.
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4.Engine Downtown 350i Remove the upper cam chain guide bolt with an 8 mm Allen. Remove the upper cam chain guide. Inspect the cam chain guides for damage and excessive wear. Replace the guides as needed. 4-78...
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4.Engine Downtown 350i Remove the cam chain from the crankshaft and crankcase. Inspect the cam chain for wear and damage. Replace the cam chain as needed. There are 11 crankcase bolts. Loosen the 11 crankcase bolts in a crisscross pattern with an 8 mm socket.
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4.Engine Downtown 350i Remove the plate with the bottom two crankcase bolts. Set the crankcases on the right side. Separate the halves of the crankcase. If needed gently tap the reinforced areas of the right crankcase half with a rubber mallet. Lift the right crankcase off of the left.
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4.Engine Downtown 350i Remove the dowel pins from the crankcase. Inspect the O-ring and replace it as needed. To remove the crankshaft see the Crankshaft topic. Replace the left crankshaft seal if the crankcases are separated. 4-81...
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4.Engine Downtown 350i Remove the seal with a seal pick. Drive the new seal into the left crankcase from the outside with a suitable driver. The driver should have the same outside diameter as the seal. Lubricate the new crankshaft seal lips with fresh engine oil.
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4.Engine Downtown 350i Assembly Thoroughly clean the crankcase mating surface. Apply sealant uniformly to the crankcase mating surface as indicated. Do not allow sealant to enter oil passages or get in bearings. Set the right case half down on top of the left. Install the engine mount spacer.
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4.Engine Downtown 350i Insert the 11 crankcase bolts. The plate goes on with the bottom two bolts. Tighten the bolts securely and evenly in a crisscross pattern with an 8 mm socket. Install the cam chain around the timing sprocket teeth on the crankshaft.
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4.Engine Downtown 350i Fit the upper cam chain guide into place. Insert the upper cam chain guide mounting bolt and tighten it to specification with an 8 mm Allen socket. Torque Thread Item size (mm) kgf-m lb-ft Cam chain tensioner pivot 0.8-1.2...
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4.Engine Downtown 350i Install the cylinder and piston. See the Cylinder and Piston topic for more information. Install the cylinder head. See the Cylinder Head topic. Install the camshaft. See the Camshaft topic for more information. Install the cylinder head cover. See the...
4.Engine Downtown 350i Crankshaft SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Split the crankcases. See the Crankcase topic for more information. Lift the crankshaft out of the left crankcase half. 4-87...
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4.Engine Downtown 350i Crankshaft Inspection Check the side clearance of the big end of the connecting rod with a feeler gauge. Item Standard (mm) Service Limit (mm) Connecting rod big Crankshaft 0.15 - 0.35 end side clearance Grip the small end of the connecting rod and try and push the rod down towards the crank weights.
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4.Engine Downtown 350i Crankshaft Bearings Inspect the crankshaft bearings for signs of damage and wear. Replace the bearings if they show any kind of imperfection. Note the bearing color code and crankcase code. The crank weights are also marked with a size code.
4.Engine Downtown 350i Engine Removal SAFETY FIRST: Protective gloves and eyewear are recommended at this point. • A floor jack or other adjustable support is required to support and maneuver the engine. Be careful not to damage the scooter body, cables and wires during engine removal.
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4.Engine Downtown 350i Drain the engine oil. See the Engine Oil topic for more information. Remove the airbox. See the Airbox topic for more information. Remove the rear brake caliper. See the Rear Brake Caliper topic for more information. Remove the throttle body. See the...
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4.Engine Downtown 350i Pull back the rubber starter motor lead cover. Remove the starter motor lead nut with a 10 mm wrench. Free the cable lead from the starter motor. Thread the nut back on to keep track of it.
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4.Engine Downtown 350i Loosen the thermostat hose clamp with a #2 Phillips screwdriver. Slide up the clamp and free the coolant hose from the thermostat. Allow any remaining coolant to drain into a suitable container. Squeeze the air bleed hose clamp with needle nose pliers and slide back the clamp.
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4.Engine Downtown 350i Loosen the main engine ground bolt with an 8 mm socket. Remove the bolt and free the engine ground from the right side of the engine. Unplug the oil pressure switch wire at the bullet connector. The oil pressure switch is located below the cylinder.
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4.Engine Downtown 350i Support the engine with a suitable jack or stand. Remove the rear shock absorbers. See the Shock Absorbers topic for more information. Hold the engine mounting bolts with a 14 mm wrench and loosen the nuts with a 19 mm socket.
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4.Engine Downtown 350i Lift up the engine mounting bracket. Carefully move the engine back and separate it from the chassis. 4-96...
5. Cooling System Downtown 350i 5.Cooling System This chapter covers the location and servicing of the cooling system components for the KYMCO Downtown 350i model. Coolant ....................5-3 Radiator ..................5-12 Water Temperature Sensor (WTS) ..........5-22 Water Pump ..................5-28 GENERAL INSTRUCTIONS • The water pump must be serviced after removing the engine. Other cooling system service can be done with the engine installed in the frame.
5. Cooling System Downtown 350i TROUBLESHOOTING Engine temperature too high • Faulty temperature gauge or sensor • Faulty radiator cap • Faulty thermostat • Insufficient coolant • Passages blocked in hoses or water jacket • Clogged radiator fins • Passages blocked in radiator •...
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5. Cooling System Downtown 350i Coolant SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Allow the engine sufficient time to cool before handling or working on the cooling system components. To check the coolant level see the...
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5. Cooling System Downtown 350i Remove the radiator cap in two stages. Allow any built up pressure to vent and then open the cap all the way and remove it. The water pump is located on the right side of the engine. Ready a drain pan under the water pump drain bolt.
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5. Cooling System Downtown 350i Remove the drain bolt and sealing washer and allow the coolant to drain into a suitable container. The coolant reserve tank is under the left floorboard. Remove the left floorboard.
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5. Cooling System Downtown 350i Remove the engine coolant lid screw with a #2 Phillips. And remove the engine coolant lid. Open the coolant reserve tank lid. Siphon the coolant out of the reserve tank with an appropriate suction device. If a suction device is unavailable remove the reserve tank and poor it out.
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5. Cooling System Downtown 350i When the coolant has fished draining return the drain bolt to the water pump with a new sealing washer. Tighten the drain bolt securely with an 8 mm socket.
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Total 1719 cc Reserve tank: 590 cc Hose: 363 cc • Use coolant of specified mixing rate. (The mixing rate of 860cc KYMCO SIGMA coolant concentrate + 859cc distilled water is 50%.) • Do not mix coolant concentrate of different brands.
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5. Cooling System Downtown 350i Add coolant to the reserve tank until it reaches the upper level mark. Gently rock the vehicle side-to-side to release any air bubbles trapped in the cooling system. Place the vehicle on its center stand and start the engine. Let it run for several minutes.
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5. Cooling System Downtown 350i Install the coolant reserve tank lid. Install the engine coolant reserve tank cover. Insert the screw and tighten its securely with a #2 Phillips. Install the left floorboard cover. 5-10...
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5. Cooling System Downtown 350i Install the front meter cover. Install the windshield. See the Windshield topic for more information. 5-11...
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5. Cooling System Downtown 350i Radiator SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Allow the engine sufficient time to cool before handling or working on the cooling system components. Pressure Testing Remove the windshield. See the Windshield topic for more information.
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5. Cooling System Downtown 350i Remove the radiator cap in two stages. Allow any built up pressure to vent and then open the cap all the way and remove it. When checking the cooling system for leaks you will need a pressure tester.
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5. Cooling System Downtown 350i Removal Drain the coolant. See the Coolant topic for more information. Unplug the cooling fan motor connector. There are three coolant hoses that connect to the radiator. The top right hose runs to the filler neck and cap. The top left hose runs to the thermostat on the cylinder head.
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5. Cooling System Downtown 350i Loosen the coolant hose clamps with a #2 Phillips screwdriver. Free the filler neck coolant hose from the stay and remove it from the radiator. Remove the water pump and thermostat hoses in the same manner.
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5. Cooling System Downtown 350i Slide the radiator to the left and free the grommet from the post above the right side of the radiator. Remove the radiator from the frame. 5-16...
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5. Cooling System Downtown 350i Coolant Reserve Tank The coolant reserve tank is mounting to the frame with two bolts. There are two hoses that connect to the reserve tank. The top hose is a dump hose that hangs over the other side. The bottom hose is the overflow hose that runs to the filler neck.
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5. Cooling System Downtown 350i Pull back the clamp and free the overflow hose from the bottom of the reserve tank. Allow the coolant in the reserve tank to drain into the container. Remove the two reserve tank mounting bolts with a 10 mm socket.
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5. Cooling System Downtown 350i To remove the reserve tank bracket take off the mounting nuts with a 10 mm socket. Remove the reserve tank bracket from the studs on the frame. 5-19...
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5. Cooling System Downtown 350i Inspection Inspect the radiator fins for damage and clogging. To remove the fan take out the three mounting bolts with a 10 mm socket. Clean out the fins with low pressure compressed air and water.
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5. Cooling System Downtown 350i Check the radiator for any bent or damaged fins. Use a small flat blade screwdriver to straighten them out, but be careful not to puncture the radiator. Jump a 12 volt battery to the fan connector and make sure the radiator fan operates.
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5. Cooling System Downtown 350i Water Temperature Sensor (WTS) Removal Drain the coolant. See the Coolant topic for more information. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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5. Cooling System Downtown 350i Use a 17 mm wrench to remove the water temperature sensor. Discard the WTS O-ring and replace it with a new item. 5-23...
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5. Cooling System Downtown 350i Thermostat Loosen the thermostat hose clamp with a #2 Phillips screwdriver. Slide up the clamp and free the coolant hose from the thermostat. Squeeze the air bleed hose clamp with needle nose pliers and slide back the clamp.
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5. Cooling System Downtown 350i Remove the two thermostat mounting bolts with an impact #3 Phillips screwdriver. Lift off the thermostat cover. 5-25...
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5. Cooling System Downtown 350i Lift out the thermostat. Remove the thermostat O-ring and discard it. Inspection Water Temperature Sensor Inspect the WTS in a simlar manner as the thermosensor. Measure the resistance between the WTS terminals and compare this to the specifications.
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5. Cooling System Downtown 350i Thermostat The thermostat should be closed at room temperature. Suspend the thermostat and a thermometer in a pot of water with string. Make sure the thermostat and the thermometer are not touching the pot. Bring the temperature up to the specification slowly and check the operation of the thermostat.
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5. Cooling System Downtown 350i Water Pump SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Mechanical Seal Inspection Inspect the telltale hole in the generator cover below the water pump for signs of coolant leaking. If there is coolant coming from this hole the mechanical seal is compromised and must be replaced.
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5. Cooling System Downtown 350i Loosen the four water pump cover bolts with an 8 mm socket. Remove the bolts and the water pump cover. Remove the two dowel pins and the water pump cover gasket. 5-29...
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5. Cooling System Downtown 350i Impeller and Shaft Remove the generator cover. See the A.C. Generator and Starter clutchtopic for more information. Hold the water pump shaft and loosen the impeller with a 12 mm socket. The impeller has left hand threads.
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5. Cooling System Downtown 350i When assembly Install the impeller to the water pump shaft. Note: Left hand threads. Hold the water pump shaft and tighten the impeller to specification with a 12 mm socket. Remember the impeller has left hand threads.
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6.Fuel System Downtown 350i 6.Fuel Injection System This chapter covers the location and servicing of the fuel system components for the KYMCO Downtown 350i model. Airbox ....................6-4 Fuel Tank ..................6-8 Fuel Pump ..................6-13 Throttle Body Removal ..............6-21 Throttle Cable .................6-32 Throttle Body ..................6-35...
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6.Fuel System Downtown 350i ● Do not snap the throttle valve from fully open to fully close after the throttle cable has been removed; it may cause incorrect idle speed. ● Do not loosen or tighten the painted bolts and screws of the throttle body.
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6.Fuel System Downtown 350i TROUBLESHOOTING Engine fail to start • Intake manifold air leak • Fuel contaminated/deteriorated • Pinched or clogged fuel hose • Faulty fuel pump • Clogged fuel filter, throttle body • Sticking fuel injector needle • Faulty fuel pump operating system •...
6.Fuel System Downtown 350i Airbox SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the air filter see the Air Filter Servicing topic for more information. Remove the seat. See the Seat topic for more information.
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6.Fuel System Downtown 350i Remove the breather hose from the airbox. Remove the two rear airbox bolts and washers.
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6.Fuel System Downtown 350i Remove the breather hose connecting of the gear box and airbox. Remove the two front airbox bolts with an 8 mm socket. And remove the airbox.
6.Fuel System Downtown 350i Fuel Tank SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Gas is extremely flammable! Do not work around an open flame or a source of sparks. Removal Seat Windshield ...
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6.Fuel System Downtown 350i In order to drain the fuel from the fuel pipe and release the fuel pressure unplug the fuel pump connecter. Start the engine and let it run until it dies of fuel starvation. Turn the ignition switch off.
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6.Fuel System Downtown 350i Note: When slide back the fuel hose carefully not to damage the fuel pump pipe, and replace the clamp with a new one when installation. Remove the fuel tank mounting nuts. 6-10...
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6.Fuel System Downtown 350i Remove the fuel tank mounting nuts. Remove the fuel tank mounting nuts and brackets. Remove the fuel tank from the bottom of the frame. 6-11...
6.Fuel System Downtown 350i Fuel Pump SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Gas is extremely flammable! Do not work around an open flame or a source of sparks. Input Voltage Inspection Remove the seat. See the Seat topic for more information.
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6.Fuel System Downtown 350i Set the engine stop switch to the “RUN” position. Unplug the fuel pump connecter. Set the multi meter to read battery voltage. Touch the multi meter leads to the harness side of the fuel pump connector, with the positive lead touching the red/black wire terminal and the negative lead touching the green wire terminal.
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6.Fuel System Downtown 350i Removal In order to drain the fuel from the fuel pipe and release the fuel pressure unplug the fuel pump connecter. Start the engine and let it run until it dies of fuel starvation. Turn the ignition switch off.
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6.Fuel System Downtown 350i Loosen the fuel hose clamp with a #2 Phillips screwdriver. Slide back the clamp and free the injector fuel hose from the fuel pump pipe. Clean up any remaining fuel immediately. Remove the 6 fuel pump bolts with a 7 mm socket or #2 Phillips screwdriver.
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6.Fuel System Downtown 350i Fuel Level Gauge Inspection Using a digital multi meter set to ohms of resistance (Ω), measure the resistance between the fuel pump/level gauge connector terminals (green and yellow/white) with the float raised to the positions indicted below.
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6.Fuel System Downtown 350i Fuel Level Float Position Resistance 1100 ± 33 Ω Full 100 ± 3 Ω Empty Replace the fuel level float unit with a new part if the resistance is out of specification. 6-18...
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6.Fuel System Downtown 350i Fuel Output Pressure Turn the key to the OFF position. Use a fuel hose clamp as shown. Disconnect the fuel hose from the fuel injector. Connect the fuel pressure gauge. Remove the fuel hose clamp. Turn the key to the ON position. Check the fuel pressure.
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6.Fuel System Downtown 350i If the fuel output pressure is less than 3.0 bar, may fail to start the engine or in trouble in case of riding. Turn the key to the OFF position and use the fuel hose clamp to block the fuel hose.
● Do not damage the throttle body, it may cause the throttle and idle valve to fail synchronization. ● The throttle body is preset in KYMCO factory, do not disassemble it incorrectly. ● Do not loosen or tighten the painted bolts and screws for the throttle body.
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6.Fuel System Downtown 350i MAP Inspection Support the scooter on a level surface. Put the side stand up and engine stop switch is at “RUN”. Turn the ignition switch to “ON” position. Measure if the ECU voltage outputs to the MAP between the following terminals of the MAP connector.
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6.Fuel System Downtown 350i TPS Inspection Support the scooter on a level surface. Put the side stand up and engine stop switch is at “RUN”. Turn the ignition switch to “ON”. Measure if the ECU voltage outputs to TPS between the following terminals of the TPS connector.
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6.Fuel System Downtown 350i Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Seat topic for more information. Adjust the throttle cables for maximum free play at the throttle body. See Throttle Free Play topic for more information.
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6.Fuel System Downtown 350i Fuel Injector SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Gas is extremely flammable! Do not work around an open flame or a source of sparks. Disconnect the Component Location Fuel Pump In order to release fuel pressure from the fuel pipe when removing the fuel injector, unplug the fuel pump connecter.
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6.Fuel System Downtown 350i Remove the fuel injector mounting bolt with a 10 mm socket. Unplug the fuel injector connector. Lift the fuel injector out of the intake pipe. Loosen the fuel hose clamp with a #2 Phillips screwdriver. Slide back the clamp and free the injector fuel pipe from the fuel hose.
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6.Fuel System Downtown 350i Lift the fuel pipe off the top of the injector. 6-27...
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6.Fuel System Downtown 350i Sensors Unplug the MAP sensor. Unplug the ISC connector. 6-28...
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6.Fuel System Downtown 350i Throttle Body Unplug the throttle position sensor (TPS) connector. Loosen the airbox hose clamp screw at the throttle body with a #2 Phillips. Loosen the intake hose clamp screw at the throttle body with a flat blade screwdriver.
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6.Fuel System Downtown 350i Remove the throttle out of the airbox and intake boots. To disassemble the throttle body see the Throttle Body topic for more information. 6-30...
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6.Fuel System Downtown 350i When installation: The throttle position sensor (TPS) and idle air bypass valve (ISC) have to be reset when the throttle body MAP, TPS, ISC or ECU have been reinstalled. See TPS ISC Reset Procedure for more information.
6.Fuel System Downtown 350i Throttle Cable SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information.
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6.Fuel System Downtown 350i Remove the two right switch housing mounting screws with a #2 Phillips screwdriver. Disconnect the switch. Separate the switch housing from the handlebar. Disconnect the throttle cables and free the right switch housing from the handlebar.
6.Fuel System Downtown 350i Notes of installation Route the throttle body end of the cables through the opening in the lower handlebar cover. Route the cables through the guide. Route the cables to the throttle body as shown. 6-34...
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6.Fuel System Downtown 350i Slide the throttle grip onto the right side of the handlebar. Install the right switch and throttle housing. The post on the housing should fit into the hole in the bar. Lubricate the end of the throttle in grease. Fit the ends of the throttle cables into the throttle tube.
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6.Fuel System Downtown 350i Throttle Body SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the throttle body. See the Throttle Body Removal and Installationtopic for more information. Disassembly The throttle position sensor (TPS) and idle air bypass valve (ISC) have to be reset when the throttle body MAP, TPS, ISC or ECU have been reinstalled.
6.Fuel System Downtown 350i MAP Sensor Remove the MAP sensor set plate screw with a #2 Phillips. Remove the set plate and MAP sensor. ISC (Air Bypass Valve) Remove the ISC screw with a #2 Phillips. Remove the ISC. 6-37...
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6.Fuel System Downtown 350i TPS Sensor Remove the TPS sensor with a T-25 Torx. Assembly TPS Sensor Apply oil onto a new O-ring. Install the TPS onto the throttle body, being careful not to damage the O-ring. Install and tighten the screw securely with a T-25 Torx.
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6.Fuel System Downtown 350i ISC (Air Bypass Valve) Apply oil onto a new O-ring. Install the ISC and set plate onto the throttle body, being careful not to damage the O-ring. Install the ISC screw and tighten securely with a #2 Phillips.
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6.Fuel System Downtown 350i MAP Sensor Apply oil onto a new O-ring. Install the MAP onto the throttle body, being careful not to damage the O-ring. Install the MAP sensor set plate screw and tighten securely with a #2 Phillips.
6.Fuel System Downtown 350i Fuel Injector SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: Gas is extremely flammable! Do not work around an open flame or a source of sparks. Removal Remove the seat. See the Seat topic for more information.
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6.Fuel System Downtown 350i Inspect the fuel hose for signs of deterioration or damaged. Replace the fuel hose as needed. Unplug the fuel injector connector. Remove the fuel injector mounting bolt with a 10 mm socket. Lift the fuel injector out of the intake pipe.
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6.Fuel System Downtown 350i Loosen the fuel hose clamp. Slide back the clamp and free the injector fuel pipe from the fuel hose. Lift the fuel pipe off the top of the injector. 6-43...
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6.Fuel System Downtown 350i Inspection A digital multi meter is needed to test the fuel injector. Measure the resistance between the fuel injector terminals. ITEM SPECIFICATIONS 9.9 - 13.5 Ω Fuel injector resistance (at 20°C/68°F) Inspect the seals on both sides of the fuel injector. Replace the injector if the seals are in poor condition.
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6.Fuel System Downtown 350i Cleaning PROBLEM 1. Fuel Injector cannot output the fuel. 2. The Injector injection time (ms) is shorter or longer. Standard: < 1.6ms ANALYSIS Injector block (With some carbons). TROUBLESHOOTING 1. Use the specified injector cleaner. 2. Pouring the liquid of carburetor cleaner until half container.
6.Fuel System Downtown 350i TPS ISC Reset Procedure SAFETY FIRST: Protective gloves and eyewear are recommended at this point. ● When opening and closing the throttle grip randomly, the ECU may record the incorrect TPS reading when the ECU or the throttle body has been reinstalled.
6.Fuel System Downtown 350i Self-Diagnosis SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Note: No matter when the CELP illuminated while riding condition, should find out the cause of the problem as soon as possible. The check engine lamp (CELP) or Fi indicator is located next to the battery warning indicator.
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6.Fuel System Downtown 350i Without Diagnostic Special Tool SELF-DIAGNOSTIC PROCEDURES Place the scooter on its main stand and put the side stand up. Set the engine stop switch to the “RUN” position. 6-48...
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6.Fuel System Downtown 350i ● Turn key to On position. ● The CELP will be lighting for two seconds and then off. ● If the engine has problem, the CELP will blink to show the failure codes. ● There’re 11 failure codes for the KEHIN system.
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6.Fuel System Downtown 350i CELP FAILURE CODES LIST Failure Blinks Contents Causes Symptoms Codes • Faulty TPS voltage range (0.3 - 4.5 V) Engine • Loose or poor connection on TPS Sensor 06 P0120 Faulty TPS operates • Open or short circuit on the TPS wire normally •...
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6.Fuel System Downtown 350i • Faulty Fuel pump fl range (F: 1100 ± 33 Ω E: 100 + 3 Ω) Faulty fuel Engine fails to be • Loose or poor connection on fuel pump 41 P0230 pump operated • Open or short circuit on fuel pump wire •...
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6.Fuel System Downtown 350i Self-Diagnosis Reset Procedure Note: The self-diagnosis memory cannot be reset when there is still a problem inside the system. 1. Put the side stand up and engine stop switch is at “RUN”. 2. Turn the key to the ON position and wait for ten seconds.
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6.Fuel System Downtown 350i Spark Plug Anti-Flood When no failure code occurs and pressing starter switch repeatedly can still not start the engine the spark plug maybe fouled and there may be a flooded engine. Perform the spark plug anti-flood to purge the fuel in the engine.
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OPERATION INSTRUCTIONS Diagnostic tool Part Number: 3620A-LEB2-E00 This tool has been developed by KYMCO and for KYMCO vehicles only. The tool software can be updated for new models with a computer via the USB cable. Please refer to the specifications when serving this vehicle.
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6.Fuel System Downtown 350i Remove the PDA panel located at the rear of the luggage box and free the PDA plug. 6-55...
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6.Fuel System Downtown 350i Plug in the tool to the ECU connector and turn on the ignition switch to send power to the tool. Place the scooter on its main stand and put the side stand up prior to using the diagnostic tool.
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6.Fuel System Downtown 350i ECU Version The four functions will display when the tool is powered on. The model name will show LEA7 for the Downtown 300i. Pressing the enter button on the ECU version will show model name, ECU number, identifications number and software version.
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6.Fuel System Downtown 350i DTC (Diagnostic Trouble Code) INSPECTION PROCEDURE Press the down button (right) to move the item selector down to the DTC Inspect item. Pressing the enter button on the DTC Inspect item will bring up the options shown above.
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6.Fuel System Downtown 350i Press the down button to select the load DTC option. Press the enter button on the Load DTC item to display the DTC options. Move the selector to the Current option and press enter to display current DTC.
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6.Fuel System Downtown 350i CELP FAILURE CODES LIST Failure Blinks Contents Causes Symptoms Codes • Faulty TPS voltage range (0.3 - 4.5 V) • Loose or poor connection on TPS Sensor Engine operates 06 P0120 Faulty TPS • Open or short circuit on the TPS wire normally •...
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6.Fuel System Downtown 350i • Faulty Fuel pump fl range (F: 1100 ± 33 Ω E: 100 + 3 Ω) Faulty fuel Engine fails to be • Loose or poor connection on fuel pump 41 P0230 pump operated • Open or short circuit on fuel pump wire •...
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6.Fuel System Downtown 350i DTC Clear Procedure Press the down button (right) to move the item selector down to the DTC Inspect item. Pressing the enter button on the DTC Inspect item will bring up the options shown above. 6-62...
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6.Fuel System Downtown 350i Move the selector down to the Clear DTC option and press enter. The diagnostic tool will show when the DTC in memory are cleared. Also, the DTC indicator light between the center and right buttons will be off.
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6.Fuel System Downtown 350i Data Analysis Procedure Press the down button (right) to move the item selector down to the DATA Analyze item. Press enter to bring up the DATA Analyze page 01 shown below. Press the down button to continue through the seven DATA Analyze pages.
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6.Fuel System Downtown 350i Page 02 The 02 page shows TPS position, intake pressure, and intake air temperature if available. Page 03 The 03 page shows atmosphere pressure, fuel injector interval, and ignition advance timing. 6-65...
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6.Fuel System Downtown 350i Page 04 The 04 page shows engine temperature, 02 sensor voltage, and 02 heater activation. Page 05 The 05 page shows the ISC target, ISC step, and ISC learn step. 6-66...
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6.Fuel System Downtown 350i Page 06 The 06 page shows the ISC motor stage. Page 07 The 07 page shows the Cut Out voltage. 6-67...
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7.CVT Continuously Variable Transmission Downtown 350i 7.CVT Continuously Variable Transmission This chapter covers the location and servicing of the CVT components for the KYMCO Downtown 350i model. Belt Case ..................7-2 CVT Removal ..................7-7 CVT Installation ................7-26 GENERAL INSTRUCTIONS • The drive pulley, clutch and driven pulley can be serviced with the engine installed.
7.CVT Continuously Variable Transmission Downtown 350i Belt Case SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the mounting bolts of belt case cover. Remove the belt case cover.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the bolts of belt case and remove the belt case. Remove the bolts of filter and remove the filter.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the belt case cover and gasket. Remove the two dowel pins.
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7.CVT Continuously Variable Transmission Downtown 350i Inspection Inspect the drive belt for cracks or excessive wear. Inspect the belt case bearing by turning it with a finger. Replace the bearing if it is rough or noisy. Remove the bearing snap ring with snap ring pliers.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the bearing with a suitable bearing puller. Drive in a new bearing with a suitable bearing driver that has the same outside diameter as the bearing. Install a new snap ring with snap ring pliers.
7.CVT Continuously Variable Transmission Downtown 350i CVT Removal SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the belt case. See the Belt Case topic for more information. Pulleys and Belt Hold the drive pulley with a universal holder tool and loosen the nut with a 19 mm socket.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the left face of the drive pulley. Loosen the driven pulley nut with a 19 mm socket. Remove the driven pulley nut and bushing.
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7.CVT Continuously Variable Transmission Downtown 350i Slide the driven pulley off of the shaft. Remove the belt from the driven pulley. Inspect the drive belt for cracks or excessive wear.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the right (movable) face of the drive pulley from the crankshaft. Slide the bushing out of the movable drive face. Remove the washer from the crankshaft. 7-10...
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7.CVT Continuously Variable Transmission Downtown 350i Drive Pulley Disassembly Inspect the faces of the drive pulley. Clean away any grease from the faces. Lift the ramp plate out of the back of the movable drive pulley face. Remove the rubber damper pieces from the ramp.
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7.CVT Continuously Variable Transmission Downtown 350i There are eight weight rollers in the back of the movable face of the drive pulley. Remove the rollers and check them for excessive or uneven wear. Measure the outside diameter of the rollers. Replace the weight rollers as needed.
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7.CVT Continuously Variable Transmission Downtown 350i Clutch Disassembly Lift the clutch outer off of the centrifugal clutch. Inspect the inside of the clutch outer for excessive wear and damage. Measure the inside diameter of the clutch outer and replace the part as needed.
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7.CVT Continuously Variable Transmission Downtown 350i Inspect the clutch shoe lining thickness. Replace the shoes if the wear is below the service limit. Item Standard (mm) Service Limit (mm) Clutch lining thickness To disassemble the clutch and driven pulley set the clutch fitting tool to onto the clutch.
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7.CVT Continuously Variable Transmission Downtown 350i Use the clutch spring compressor tool to compress the spring in the driven pulley assembly. Secure the spring compressor tool in a vise. Loosen the clutch drive plate nut with the special socket that comes with the fitting tool.
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7.CVT Continuously Variable Transmission Downtown 350i Inspect the left side bearing by turning it with a finger. If the bearing is rough turning or noisy it should be replaced. Remove the clutch spring compressor tool. Lift off the centrifugal clutch.
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7.CVT Continuously Variable Transmission Downtown 350i Remove the collars and spring. Measure the free length of the clutch spring. Replace the spring if the measurement fails to meet the service limit. 7-17...
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7.CVT Continuously Variable Transmission Downtown 350i Remove the three circlips from the clutch pivot pins with a small flat blade screwdriver. Lift off the plate. Slide the clutch shoes off of the pivots on the drive plate. 7-18...
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7.CVT Continuously Variable Transmission Downtown 350i Inspect the clutch shoe bumpers and replace them as needed. 7-19...
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7.CVT Continuously Variable Transmission Downtown 350i Driven Pulley Disassembly Remove the clutch as shown above. Remove the four guide rollers with guide roller pins. Separate the left and right faces of the driven pulley. 7-20...
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7.CVT Continuously Variable Transmission Downtown 350i Inspect the faces of the driven pulley. Clean away any grease from the faces where the belt rides. Remove the seals from the left face of the driven pulley. 7-21...
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7.CVT Continuously Variable Transmission Downtown 350i Drive in the new seals with a suitable driver with the same outside diameter as the seal. Remove the O-rings on the left face. Clean the left face and roller pins with a high flash point solvent and compressed air.
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7.CVT Continuously Variable Transmission Downtown 350i Bearing Replacement Inspect the bearings in the right face of the driven pulley. Remove the needle bearing with a suitable puller. 7-23...
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7.CVT Continuously Variable Transmission Downtown 350i Remove the collar, snap ring, and bearing from the right face of the driven pulley. Clean the right face with a high flash point solvent and compressed air. NOTE: Always wear safety glasses when using compressed air and never point it directly at yourself or anyone else.
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7.CVT Continuously Variable Transmission Downtown 350i Lubricate the bearings in the right face of the driven pulley with grease. 7-25...
7.CVT Continuously Variable Transmission Downtown 350i CVT Installation SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Driven Pulley Lubricate the bearings in the right face of the driven pulley with grease. Drive in the new seals with a suitable driver with the same outside diameter as the seal.
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7.CVT Continuously Variable Transmission Downtown 350i Install the O-rings to the left face of the driven pulley. Coat the O-rings seals, and inside of the left face where it rides on the right face with grease. Fit the left face onto the right face. Wipe away any grease that gets on the faces where the belt will ride.
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7.CVT Continuously Variable Transmission Downtown 350i Lubricate the guide pins and rollers with grease. Place the rollers on the pins and insert the pins into driven pulley as shown. Clutch Apply a light coat of grease to the brake shoe pivot pins on the drive plate. Install the three rubber bumpers.
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7.CVT Continuously Variable Transmission Downtown 350i Connect the clutch shoes with the springs as shown. Slide the clutch shoes onto the drive plate pivots. Fit the plate onto the clutch shoe pivots. 7-29...
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7.CVT Continuously Variable Transmission Downtown 350i Install the three clutch shoe pivot circlips. Install the seal collar and spring. Install the spring collar into the spring and set the centrifugal clutch on top of the spring collar. 7-30...
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7.CVT Continuously Variable Transmission Downtown 350i Set the clutch fitting tool to onto the clutch. Use the clutch spring compressor tool to compress the spring in the driven pulley assembly. Thread on the clutch drive plate nut. 7-31...
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7.CVT Continuously Variable Transmission Downtown 350i Tighten the clutch drive plate nut to specification with the special socket that comes with the fitting tool. Torque Item kgf-m lb-ft Clutch drive plate nut 55.32 Wipe away any excess grease. Do not allow grease to contact the clutch shoe linings or the driven faces where the belt will ride.
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7.CVT Continuously Variable Transmission Downtown 350i Drive Pulley Install the rollers into the back of the movable drive face of the driven pulley. Position the rollers so that their colored sides are clockwise. Insert the four rubber damper pieces into the ramp.
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7.CVT Continuously Variable Transmission Downtown 350i Pulleys and Belt Slide the drive pulley washer onto the crankshaft. Insert the bushing into movable drive face of the drive pulley. Slide the movable face of the drive pulley onto the crankshaft. Make sure the drive face are clean and grease free where they will contact the belt.
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7.CVT Continuously Variable Transmission Downtown 350i Fit the Belt in between the faces of the driven pulley. Spread the faces by had if needed in get the belt to fit. Slide the driven pulley and clutch assembly onto the final drive shaft. Position the front end of the belt around the crankshaft.
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7.CVT Continuously Variable Transmission Downtown 350i Install the driven pulley bushing and nut. Torque the driven pulley nut to specification with a 19 mm socket. Torque Thread Item size (mm) kgf-m lb-ft Clutch outer nut (driven pulley) 5.0-6.0 36.17-43.40 7-36...
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7.CVT Continuously Variable Transmission Downtown 350i Slide the left face of the drive pulley onto the crankshaft. Lubricate the threads of the drive pulley nut with engine oil. Install the drive pulley washer and nut. 7-37...
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7.CVT Continuously Variable Transmission Downtown 350i Hold the drive pulley with a universal holder tool and torque the nut to specification with a 19 mm socket. Torque Thread Item size (mm) kgf-m lb-ft Drive face nut 9.0-10.0 65.10-72.33 Install the belt case. See the Belt Case topic for more information.
8.Final Drive Downtown 350i 8.Final Drive This chapter covers the location and servicing of the final drive components for the KYMCO Downtown 350i model. Final Drive Oil .................8-3 Final Reduction ................8-8 Downtown 350i parts diagram. GENERAL INSTRUCTIONS • The servicing operations of this section can be made with the engine installed.
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8.Final Drive Downtown 350i TROUBLESHOOTING Engine starts but motorcycle won't move • Damaged transmission • Seized or burnt transmission Abnormal noise • Worn, seized or chipped gears • Worn bearing Oil leaks • Oil level too high • Worn or damaged oil seal...
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8.Final Drive Downtown 350i Final Drive Oil SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Place the scooter on level ground and up on its center stand. The oil drain bolt and oil filler bolt are located on the transmission.
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8.Final Drive Downtown 350i Draining Place the vehicle on its center stand on level ground. Place a suitable oil drain pan under the transmission oil drain plug. Remove the transmission oil level filler bolt with a 12 mm socket. Place a suitable container under the drain plug to capture the final drive oil.
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8.Final Drive Downtown 350i Inspect the drain plug and washer. Install the oil drain plug and washer with a 12 mm socket. Tighten to specification. Torque Thread Item size (mm) kgf-m lb-ft Final drive oil drain bolt 0.8 - 1.2...
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8.Final Drive Downtown 350i Filling Fill the final drive with the specified quantity of oil with a syringe. Gear oil type: SAE 90 Gear oil capacity: At disassembly 0.23 Liter At change 0.21 Liter Thread in the final drive oil level filler bolt.
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8.Final Drive Downtown 350i Install the oil filler plug and torque it to specification with a 12 mm socket. Torque Thread Item size (mm) kgf-m lb-ft Final drive oil filler bolt 0.8 - 1.2 5.79 - 8.68...
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8.Final Drive Downtown 350i Final Reduction SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Disassembly Note:Do not remove the transmission case cover except for necessary part replacement. If the drive shaft is replaced, make sure to also replace the bearing and oil seal.
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8.Final Drive Downtown 350i Remove the 9 transmission case cover bolts using a 12 mm socket. Utilize the reinforced pry points and remove the case cover.
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8.Final Drive Downtown 350i Use a press to remove the drive shaft. Thread a nut onto the drive shaft to protect the threads. If the drive shaft is to be replaced also replace the seal. Remove the two dowel pins and the gasket.
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8.Final Drive Downtown 350i Remove the countershaft. Remove the final shaft. 8-11...
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8.Final Drive Downtown 350i Inspection Inspect the countershaft gear for wear or damage. Inspect the final gear and final shaft for wear, damage or seizure. If the final shaft snap ring is removed replace it with a new item. Check the left crankcase bearings for excessive play. Inspect the oil seal for wear or damage.
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8.Final Drive Downtown 350i Check the transmission case cover bearings for excessive play. Inspect the drive shaft, drive shaft bearing and oil seal for wear or damage. Use a bearing puller to remove the crankcase or transmission case covers. Use a seal pick to remove the oil seals.
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8.Final Drive Downtown 350i Use a bearing driver to install any new bearings into the crankcase and transmission case cover. The driver should have the same outside diameter as the bearings. The bearings should go in square and have their markings facing out.
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8.Final Drive Downtown 350i Insert the final shaft through the oil seal and bearing. Install the countershaft into its bearing as shown. Install the final gear onto the final shaft as shown. Install the dowel pins. Install a new gasket onto the transmission case.
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8.Final Drive Downtown 350i Install the transmission case cover onto the transmission. Fit the drive into its bearing in the case and make sure it gear engages correctly with the countershaft gear. Turn the drive shaft and make sure the final shaft turns.
9.Electrical Systems Downtown 350i 9.Electrical Systems This chapter covers the location and servicing of the electrical systems for the KYMCO Downtown 350i model. Electrical Specifications ..............9-8 Fuses ....................9-10 ECU Removal .................9-11 Ignition System ................9-15 Charging System ................9-22 Battery .....................9-24 Relays .....................9-28 Starting System ................9-30...
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9.Electrical Systems Downtown 350i • If a battery is not used for a long time, it will discharge by itself and should be recharged every 3 months. • A new battery filled with electrolyte will generate voltage within a certain time and it should be recharged when the capacity is insufficient.
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9.Electrical Systems Downtown 350i TROUBLESHOOTING No power • Dead battery • Disconnected battery cable • Fuse burned out • Faulty ignition switch Intermittent power • Loose battery cable connection • Loose charging system connection • Loose connection or short circuit in the ignition system Low power •...
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9.Electrical Systems Downtown 350i Ignition System GENERAL INSTRUCTIONS • Some electrical components may be damaged if terminals or connectors are connected or disconnected while the ignition switch is “ON” and current is present. • When servicing the ignition system, always follow the steps in the troubleshooting on page above.
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9.Electrical Systems Downtown 350i TROUBLESHOOTING No peak voltage • Short circuit in engine stop switch or ignition switch wire. • Faulty engine stop switch or ignition switch. • Loose or poorly connected ignition control module connectors. • Open circuit or poor connection in ground wire of the ignition control module.
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9.Electrical Systems Downtown 350i TROUBLESHOOTING Starter motor will not turn • Fuse burned out • Weak battery • Faulty ignition switch • Faulty starter clutch or gear • Faulty front or rear stop switch • Faulty starter relay • Poorly connected, broken or shorted wire •...
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9.Electrical Systems Downtown 350i • Check the battery condition before performing any inspection that requires proper battery voltage. • A continuity test can be made with the switches installed on the scooter. • Route the wires and cables properly after servicing each component.
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9.Electrical Systems Downtown 350i Electrical Item Standard Capacity 12V 10AH Fully charged 13.2V Battery Voltage (20°C) Insufficient charged < 12.3V Charging current 1.2A* 5 - 10H Item Standard Spark plug Standard type NGKCR7E Spark plug gap 0.6 - 0.7 mm 3.57 - 4.83 Ω...
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9.Electrical Systems Downtown 350i 18.8 KΩ At -20°C/-4°F Water temperature 1.136 KΩ At 40°C/104°F sensor resistance 0.1553 KΩ At 100°C/212°F Item Standard Service Limit Starter motor brush length 12.5 mm 8.5 mm Fuse 10A,15A,30A,40A(ABS Model) Headlight bulb 12V 55W/55W *2...
9.Electrical Systems Downtown 350i Fuses SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Fuse Box Remove the seat and the luggage box. See the Seat topic for more information. The fuse box is located on top of the battery.
9.Electrical Systems Downtown 350i ECU Removal SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the front cover. See the Front Cover topic for more information. Note: The ignition control module or ECU maybe damaged if dropped or the connector is disconnected when the key is “...
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9.Electrical Systems Downtown 350i Remove the two mounting nuts with a socket. Remove the bracket and remove the ECU. 9-12...
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9.Electrical Systems Downtown 350i Inspection Check for continuity between pin 9 and 10 of the ECU side connector. There should be continuity at all times. Check for continuity between each pins 2, 4 and 23 of the ECU side connector.
9.Electrical Systems Downtown 350i Ignition System SAFETY FIRST: Protective gloves and eyewear are recommended at this point. The ignition timing is set at the factory and is not adjustable. Perform the following checks. Before performing any tests make sure the electrical connections are not loose or corroded.
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9.Electrical Systems Downtown 350i Ignition Coil Removal Remove the two ignition coil leads. Remove the two ignition coil mounting bolts with an 8 mm socket. Remove the ignition coil. 9-15...
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9.Electrical Systems Downtown 350i Ignition Coil Resistance Primary Set the multimeter to read ohms of resistance (Ω). Touch the positive and negative meter leads to the ignition coil terminals as shown. Measure the resistance. 3.57 - 4.83 Ω Ignition Coil Primary Resistance...
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9.Electrical Systems Downtown 350i Check the secondary resistance between the ignition coil terminal and the spark plug cap. Touch the negative meter lead to the terminal and the positive meter lead to the spark plug cap as shown. 15 - 19 kΩ...
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9.Electrical Systems Downtown 350i AC Generator Inspection Crank Position Sensor Inspection Note: This test is performed with the stator installed in the engine. Disconnect the crank position sensor wire coupler. Measure the resistance between the and green/white and blue/yellow wire terminals.
9.Electrical Systems Downtown 350i Charging System SAFETY FIRST: Protective gloves and eyewear are recommended at this point. You will need a digital multimeter to inspect the charging system. To replace the stator/charging coil see the A.C. Generator and Starter clutch topic.
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9.Electrical Systems Downtown 350i Regulator/Rectifier Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. The regulator/rectifier is located on the left side of the vehicle. Disconnect the regulator/rectifier connector. Check the connectors for loose contacts or corroded terminals.
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9.Electrical Systems Downtown 350i Battery Wire Measure the voltage between the Red/White wire terminal and ground. There should be battery voltage at all times. Ground Wire Check the continuity between the Green wire terminal and ground. There should be continuity at all times.
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9.Electrical Systems Downtown 350i Charging Coil Wire Disconnect the generator 3-pin connector. Check the connectors for loose contacts or corroded terminals. Measure the resistance between each Yellow wire terminals. Check for continuity between each yellow wire terminal regulator/rectifier side and ground. There should be no continuity.
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9.Electrical Systems Downtown 350i Removal Disconnect the two regulator/rectifier connectors. Remove the two mounting nuts with a 10 mm socket. Remove the regulator/rectifier. 9-23...
9.Electrical Systems Downtown 350i Battery SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Warning: The battery electrolyte (sulfuric acid) is poisonous and may seriously damage the skin and eyes. Avoid contact with skin, eyes, or clothing. In case of contact, flush with water and get prompt medical attention.
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9.Electrical Systems Downtown 350i The battery is located in the back of the vehicle. Remove the negative battery cable bolt with a 10 mm socket or #3 Phillips screwdriver. Free the negative cable from the battery. Remove the positive battery cable bolt with a 10 mm socket or #3 Phillips screwdriver.
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9.Electrical Systems Downtown 350i Lift the battery out of the battery tray. Testing Check the battery voltage with a multi-meter. Place the positive probe onto the positive battery terminal and the negative probe to the negative battery terminal. If the battery reads under 12.3 V it is undercharged.
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9.Electrical Systems Downtown 350i Battery Charging Charge the battery with a motorcycle specific battery charger at the specified rate. Connect the charger leads to their appropriate battery terminals. Keep open flames away from a charging battery. Standard Charge 1.2 Amps...
9.Electrical Systems Downtown 350i Relays SAFETY FIRST: Protective gloves and eyewear are recommended at this point. 9-28...
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9.Electrical Systems Downtown 350i Inspection Use a digital multimeter to inspect the fuel cut-off relay (Fuel Pump Relay). Set the multimeter to read ohms of resistance. Connect the multimeter to the fuel cut-off relay connector terminals. Connection: Black - Red/Black Connect 12 V battery with the fuel cut-off relay connector.
9.Electrical Systems Downtown 350i Starting System SAFETY FIRST: Protective gloves and eyewear are recommended at this point. You will need a digital multimeter to inspect the starting system. Starter Relay Inspection Remove the body cover. See the Body Cover topic for more information.
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9.Electrical Systems Downtown 350i Check for continuity between the yellow/red wire and green/yellow wire. There should be continuity when the starter button is depressed. If there is no continuity, check the starter button for continuity and inspect the wire. Operation Test Remove the battery cover.
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9.Electrical Systems Downtown 350i Remove the two terminal covers. Remove the nuts that hold the starter motor lead and battery lead wires to the starter relay with a 10 mm socket. 9-32...
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9.Electrical Systems Downtown 350i Disconnect the starter relay wire connector. And remove the starter relay. Connect the electric meter to the starter relay terminals that connect to the battery positive cable and the starter motor cable. Connect a fully charged battery across the starter relay yellow/red and green/yellow wire terminals.
9.Electrical Systems Downtown 350i Starter Motor SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the battery cover. See the Battery topic for more information. Turn the ignition switch to "OFF". Remove the negative battery cable bolt with a 10 mm socket or #3 Phillips screwdriver.
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9.Electrical Systems Downtown 350i Remove the starter motor lead nut with a 10 mm wrench. Free the cable lead from the starter motor. Thread the nut back on to keep track of it. Remove the two starter motor mounting bolts with an 8 mm socket.
9.Electrical Systems Downtown 350i Switches SAFETY FIRST: Protective gloves and eyewear are recommended at this point. You will need a digital multimeter to inspect the switches. Ignition Switch Unplug the white six-pin ignition switch connector. 9-36...
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9.Electrical Systems Downtown 350i Use a digital multimeter to check for continuity to inspect the ignition switches. Continuity should exist between the wires as indicated. 9-37...
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9.Electrical Systems Downtown 350i Removal Remove the seat latch cable cover. 9-38...
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9.Electrical Systems Downtown 350i Loosen the seat latch cable screw with a #2 Phillips screwdriver. Remove the seat latch cable screw and free the seat latch cable from the ignition switch. To remove the anti-tamper bolts use a punch and a hammer to strike the bolts so that they rotate loose.
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9.Electrical Systems Downtown 350i Tilt Switch Remove the front cover. See the Front Cover topic for more information. Support the scooter level surface. Put the side stand up and engine stop switch on “RUN”. Turn the ignition switch to “OFF”.
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9.Electrical Systems Downtown 350i Incline the tilt switch 65±10 degrees to the left or right at the ignition switch “ON”. Measure the voltage as below. Terminal Standard Violet/Red (+) ~ Green/Pink (-) 5 V (ECU voltage) Black/Blue (+) ~ Green/Pink (-) 3.7 - 4.4 V...
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9.Electrical Systems Downtown 350i Handlebar Switches Remove the front cover. See the Front Cover topic for more information. To remove the handle bar switches see the Handlebar topic. Unplug the black connector for the left handlebar switches. Unplug the green connector for the right handlebar switches.
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9.Electrical Systems Downtown 350i Right Handlebar Switches Use a digital multimeter to check for continuity to inspect the handlebar switches. Continuity should exist between the wires as indicated. 9-43...
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9.Electrical Systems Downtown 350i Left Handlebar Switches Use a digital multimeter to check for continuity to inspect the handlebar switches. Continuity should exist between the wires as indicated. 9-44...
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9.Electrical Systems Downtown 350i Luggage Box Switch Remove the luggage box. See the Luggage Box topic for more information. Unplug the two-pin luggage box light switch connector with red/white and green/red wires. Remove the luggage box light and switch. 9-45...
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9.Electrical Systems Downtown 350i Side Stand Switch Remove the luggage box. See the Luggage Box topic for more information. Place the vehicle on the center stand. Unplug the three-pin side stand switch connector. Use a digital multimeter to check for continuity.
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9.Electrical Systems Downtown 350i Brake Light Switches Test the front and rear brake light switches in the same manner. Use a digital multimeter to check for continuity. Remove the upper handlebar cover. See the Handlebar Covers topic for more information.
9.Electrical Systems Downtown 350i Lights SAFETY FIRST: Protective gloves and eyewear are recommended at this point. For general information and troubleshooting for the lights see the Electrical Systems chapter landing page. Headlight Bulb Replacement Make sure the machine has been off for several minutes before removing the headlight bulb.Remove the front cover.
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9.Electrical Systems Downtown 350i Remove the front position LED connecter. Slide back the head light bulb connecter. 9-49...
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9.Electrical Systems Downtown 350i Loosen the screw and spring. Unplug the bulb from its connector. Do not touch the bulb with your bare hands if you plan to reuse it. Do not touch your new bulb with your bare hand. The oils on your hand can cause an early failure of the headlight bulb.
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9.Electrical Systems Downtown 350i Turn the screws to adjust the head light aim as needed. 9-51...
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9.Electrical Systems Downtown 350i Front Turn Signals Remove 3 screws of the turn signal light set. And remove the turn signal light set. Replace the turn signal light bulb if needed. 9-52...
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9.Electrical Systems Downtown 350i Rear turn signal lights Bulb Replacement Lift the seat. See the Seat topic for more information. Remove the turn signal sockets with bulbs from the turn signal lamps. Remove the bulbs from the tail light housing by turning it counterclockwise.
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9.Electrical Systems Downtown 350i Tail/Stop light(LED) Remove the rear cover. See the Body Cover topic for more information. Repalce Check the tail/stop light (LED), if the LED fail to light replace the whole module with a new one. Change the whole set if the rear turn signal LED fail to light.
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9.Electrical Systems Downtown 350i License Tag Light Remove the license tag light from the mud flap. See the Body Cover topic for more information. Remove the screws. Pull the rubber tag light socket out of its housing. Pull the bulb straight out and insert a new one.
9.Electrical Systems Downtown 350i Horn SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the front cover. See the Front Cover for more information. Disconnect the horn connectors from the horn. Connect a 12 V battery to the horn terminals.
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10..Brake System Downtown 350i 10.Brakes This chapter covers the location and servicing of the brake system components for the KYMCO Downtown 350i model. Brake Pad Replacement ..............10-2 Master Cylinders ................10-13 Master Cylinders ................10-22 Front Brake Caliper ................10-26 Rear Brake Caliper .................10-31 Brake Disc ..................10-37...
10..Brake System Downtown 350i Brake Pad Replacement SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Replace the pads if the brake wear exceeds the wear indicator lines or if the wear is uneven.
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10..Brake System Downtown 350i Front Remove the screw and loosen the brake pad pin with a 5 mm Allen. Remove the two caliper mounting bolts with a 12 mm socket. And remove the front caliper.
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10..Brake System Downtown 350i Remove the speedometer sensor mounting bolt with an 8 mm socket. And remove the speedometer sensor. Remove the brake pad pin. Remove the brake pads. Replace the pads if the brake wear exceeds the wear indicator lines or if the wear is uneven. Insert new brake pads as needed.
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10..Brake System Downtown 350i Fit the ends of the pads into the pad retainer as shown. Apply a light coat of waterproof grease to the brake pad pin. Push the pads against the pad spring and insert the brake pad pin.
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10..Brake System Downtown 350i Install the front caliper. Guide the brake disc between the pads. Line up the caliper bracket mounts with the fork. Install the two caliper bracket mounting bolts. Tighten the mounting bolts to specification. Torque Item lb-ft Front/Rear caliper bolt 25.8...
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10..Brake System Downtown 350i Install the speedometer sensor. Install the speedometer sensor mounting bolt with an 8 mm socket. Torque Item lb-ft Speed sensor cable 9.80 - 13.73 7.23 - 10.13 Tighten the brake pad pin securely with a 5 mm Allen.
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10..Brake System Downtown 350i Rear Remove the muffler. See the Exhaust System topic for more information. Remove the rear fender. See the Rear Fender topic for more information. If the caliper is to be disassembled the brake hose must be removed. Drain the rear brake fluid.
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10..Brake System Downtown 350i Remove the two rear caliper mounting bolts with a 12 mm socket. Remove the rear caliper from the swingarm.
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10..Brake System Downtown 350i One at a time, move the brake pads to the center gap in the pad retainers and lift the pad out. If needed, use the piston side pad to push the pistons in to allow for more room.
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10..Brake System Downtown 350i One at a time, fit the brake pads into the center gap in the pad retainers and then move the pad into the retainer. If needed, use the piston side pad to push the pistons in to allow for more room.
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10..Brake System Downtown 350i Fit the rear brake hose guide into place. Insert the two rear brake hose clamp bolts and tighten them securely with a socket. Fill the rear brake system with fresh brake fluid and bleed out the air. See Brake Fluid topic for more information.
10..Brake System Downtown 350i Master Cylinders SAFETY FIRST: Protective gloves and eyewear are recommended at this point. NOTE: Brake fluid is a corrosive chemical and can damage paints and some plastics. Avoid contact with skin. Removal The master cylinders for the front and rear brakes are essentially the same.
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10..Brake System Downtown 350i Unplug the brake light switch connector. Remove the two master cylinder mounting bolts with an 8 mm socket. Remove the master cylinder clamp. Remove the master cylinder. 8-14...
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10..Brake System Downtown 350i Remove the two master cylinder cover screws with a #2 Phillips head screwdriver. Remove the master cylinder cover, plastic piece and rubber accordion diaphragm. Pour out any remaining brake fluid. 8-15...
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10..Brake System Downtown 350i Disassembly Brake Levers Loosen the brake lever pivot nut with a 10 mm socket and the pivot bolt with a flat blade screwdriver. Remove the pivot nut and bolt. Remove the brake lever. 8-16...
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10..Brake System Downtown 350i Brake Light Switch Remove the brake light switch mounting bolt with a #2 Phillips screwdriver. Remove the brake light switch. Piston Remove the rubber piston cover. Remove the snap ring using a pair of internal snap ring pliers. Use a suitable tool to hold back the piston as it can spring out.
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10..Brake System Downtown 350i Remove the piston, spring and cups. Remove the spring from the piston and 8-18...
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10..Brake System Downtown 350i Inspection Clean the master cylinder components with fresh brake fluid. Inspect the master cylinder components for wear and damage. Replace the parts as needed Inspect the piston and cups for wear and damage. Measure the outside diameter of the piston.
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10..Brake System Downtown 350i Assembly Piston Place a film of clean DOT 4 brake fluid on the piston, spring and master cylinder bore. Install the master cylinder piston and spring into the master cylinder bore. Compress the snap ring with internal snap ring pliers and Install the snap ring.
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10..Brake System Downtown 350i Install the rubber boot over the end of the master cylinder piston. 8-21...
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10..Brake System Downtown 350i Brake Light Switch Install the brake light switch. Tighten the mounting screw securely with a #2 Phillips screwdriver. Brake Levers Install the brake lever. 8-22...
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10..Brake System Downtown 350i Apply a light coat of grease to brake lever pivot bolt. Insert the pivot bolt from above and thread on the nut. Tighten the brake lever bolt with a flat blade screwdriver and then tighten the nut with a 10 mm socket.
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10..Brake System Downtown 350i Installation Position the master cylinder on the handlebar. Install the master cylinder clamp. Be sure to insert the pin on the clamp into the hole on the handlebar. Install the two master cylinder mounting bolts and tighten them securely with an 8 mm socket.
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10..Brake System Downtown 350i Plug in the brake light switch connector. Install the brake hose to the master cylinder with the banjo bolt. Use new sealing washers. Tighten the banjo bolt to specification with a 12 mm socket. Torque Item...
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10..Brake System Downtown 350i Front Caliper SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the screw and loosen the brake pad pin with a 5 mm Allen. Remove the two caliper mounting bolts with a 12 mm socket.
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10..Brake System Downtown 350i Remove the speedometer sensor mounting bolt with an 8 mm socket. And remove the speedometer sensor. Remove the brake pad pin. Remove the brake pads. Replace the pads if the brake wear exceeds the wear indicator lines or if the wear is uneven. Insert new brake pads as needed.
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10..Brake System Downtown 350i Fit the ends of the pads into the pad retainer as shown. Apply a light coat of waterproof grease to the brake pad pin. Push the pads against the pad spring and insert the brake pad pin.
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10..Brake System Downtown 350i Inspection Inspect the pistons for wear and damage. Measure the outside diameter of the piston with a micrometer and compare the measurement with the specification. Replace the pistons as needed. Item Standard mm (in) Brake caliper piston O.D.
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10..Brake System Downtown 350i Inspect the piston bores for wear and damage. Inspect the piston bores for wear and damage. Measure the inside diameter of the piston bore with a telescoping gauge and micrometer. Replace the caliper as needed. Item Standard mm (in) Brake caliper cylinder I.D.
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10..Brake System Downtown 350i Rear Remove the muffler. See the Exhaust System topic for more information. Remove the rear fender. See the Rear Fender topic for more information. If the caliper is to be disassembled the brake hose must be removed. Drain the rear brake fluid.
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10..Brake System Downtown 350i Remove the two rear caliper mounting bolts with a 12 mm socket. Remove the rear caliper from the swingarm. 8-32...
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10..Brake System Downtown 350i Place a suitable container under the banjo bolt to catch any remaining brake fluid. Remove the banjo bolt that holds the brake hose to the caliper using a 12 mm socket. Discard the two sealing washers.
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10..Brake System Downtown 350i Installation Install the rear caliper onto the swingarm. Install the two caliper bracket mounting bolts. Tighten the mounting bolts to specification. Torque Item lb-ft Front/Rear caliper bolt 25.8 8-34...
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10..Brake System Downtown 350i Install the banjo bolt with new sealing washers and tighten to specification with a 12 mm socket. Torque Item lb-ft Banjo bolt 25.8 Fit the rear brake hose guide into place. 8-35...
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10..Brake System Downtown 350i Insert the two rear brake hose clamp bolts and tighten them securely with a 10 mm socket. Fill the rear brake system with fresh brake fluid and bleed out the air. See Brake Fluid topic for more information.
10..Brake System Downtown 350i Disc Brake Inspection Measure the thickness of the brake rotor with a Vernire caliper or micrometer. ITEM STANDARD 3.8 - 4.2 mm Front (0.15 - 0.165 in) Brake disc thickness 5.0 mm Rear (0.2 in) Check if the brake rotor runout is within service limit.
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10..Brake System Downtown 350i Front Removal Remove the front wheel. See the Front Wheel topic for more information. Remove the five brake disc mounting bolts with an Allen wrench. 8-38...
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10..Brake System Downtown 350i Remove the front brake disc and front wheel speed sensor rotor. Separate the wheel speed sensor rotor from the brake disc. 8-39...
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10..Brake System Downtown 350i Inspect the wheel speed sensor and brake disc for wear and damage. Replace the parts as needed. Set the front brake disc and speed sensor rotor in place on the front wheel. 8-40...
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10..Brake System Downtown 350i Installation Coat the threads of the disc bolts in a non-permanent thread locking agent. Thread in the bolts and torque them to specification with an Allen socket. Set the speed sensor rotor on the front brake disc. Position the rotor so that its sharp side sits against the brake disc.
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10..Brake System Downtown 350i SAFETY FIRST: Protective gloves and eyewear are recommended at this point. ABS Component Location 1. Front Wheel speed Sensor 2. Front Wheel speed Sensor Rotor 3. Rear Wheel speed Sensor 4. Rear Wheel speed Sensor Rotor 5.
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10..Brake System Downtown 350i Introduction to KYMCO Anti-Lock Brake System ABS is designed to help prevent the wheels from locking up when the brakes are applied hard while running straight. The ABS automatically regulates brake force. Intermittently gaining gripping force and braking force helps prevent wheel lock-up and allows stable steering control while stopping.
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10..Brake System Downtown 350i Caution: Use of non-recommended tires may cause malfunctioning of ABS and lead to extended braking distance. The rider could have an accident as a result. Always use the standard tires for this vehicle. Notice: When the ABS is functioning,you may feel a pulsing in the brake lever. This is normal - you need not suspend applying the brakes.
10..Brake System Downtown 350i ABS Servicing Precautions There are a number of important precautions that should be followed servicing the ABS system. □ This ABS system is designed to be used with a 12V sealed battery as its power source.
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10..Brake System Downtown 350i Caution If any of the brake line fittings, including the ABS hydraulic unit joint nuts, or the bleed valve are opened at any time, the air must be bled completely from the brake line. Do not ride the scooter with air in the brake line, or the ABS could malfunction.
10..Brake System Downtown 350i ABS Troubleshooting Outline The ABS indicator light lights up to alert the rider when an abnormality is detected by the system. The service codes are stored in the ABS unit memory. The codes will not be erased unless manually cleared.
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10..Brake System Downtown 350i Meter Instruments (For models equipped with ABS) The ABS indicator light is on the right side of the meter. This light will comes on when the ignition switch is turned on and goes off shortly after the vehicle starts moving. The light stays off as long as the system is ok.
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10..Brake System Downtown 350i ABS Indicator Light Is Unlit (When The Ignition Switch Turned To ON) 1st step test. Disconnect the meter connector. Check the terminal voltage between the ABS signal wire (Pink lead) terminal of the meter connector and ground. Turn the ignition switch ON.
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10..Brake System Downtown 350i 3rd step test. Disconnect the ABS hydraulic unit connector. Check for continuity between the ABS signal wire (Pink lead) terminal of the meter side connector and the ABS signal wire (Pink lead) terminal of the ABS unit side connector.
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10..Brake System Downtown 350i ABS Indicator Light lights (When the scooter is running, - no service code) 1st step test. Disconnect the ABS hydraulic unit connector and meter connector. Check for continuity between the ABS signal wire (Pink lead) terminal of the meter side connector and the ABS signal wire (Pink lead) terminal of the ABS unit side connector.
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10..Brake System Downtown 350i Front, Rear Wheel Rotation Difference Abnormal (service code 25) 1st step test. Check the following and correct the faulty part. 1. Incorrect the tire pressure 2. Tire not recommended for the scooter were installed (incorrect tire size).
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10..Brake System Downtown 350i ABS Motor Relay Inspection (service code 35) 1st step test. Check the ABS motor relay fuse (25A). Front Wheel Rotation Sensor Signal Abnormal (service code 42) 1st step test. Measure the clearance between the front wheel rotation sensor and sensor rotor.
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10..Brake System Downtown 350i Front Wheel Rotation Sensor Wiring Inspection (service code 43) 1st step test. Disconnect the ABS hydraulic unit connector and front wheel sensor connector. Short the white/brown and red-green lead terminals of the main harness side connector with a jumper lead, and check for continuity between the white/brown and red green lead terminals of the main harness side connector.
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10..Brake System Downtown 350i Rear Wheel Rotation Sensor Wiring Inspection (service code 45) 1st step test. Disconnect the ABS hydraulic unit connector and rear wheel sensor connector. Short the light-blue/brown and black/red lead terminals of the main harness side connector with a jumper lead, and check for continuity between the light-blue brown and black/red lead terminals of the main harness side connector.
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10..Brake System Downtown 350i Power Supply Voltage Abnormal (under-voltage) (service code 52) 1st step test. Disconnect the ABS diagnosis connector and ABS hydraulic unit connector. Check for continuity for the black lead terminal of the main harness side connector. 2nd step test.
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10..Brake System Downtown 350i Power Supply Voltage Abnormal (over-voltage) (service code 53) 1st step test. Disconnect the ABS diagnosis connector and ABS hydraulic unit connector. Check for continuity for the black lead terminal of the main harness side connector. 2nd step test.
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10..Brake System Downtown 350i ECU Inspection (service code 55) 1st step test. Recheck the service code indication; erase the service code, perform the pre-diagnosis inspection 1 and 2, and retrieve the service code. If the ABS indicator light lit. faulty ECU in the ABS hydraulic unit. Replace the ABS hydraulic unit.
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10..Brake System Downtown 350i ABS Diagnostic Tool Connect the diagnostic tool and set the ECU to the ABS. See the Diagnostic Tool topic for more information. 8-61...
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10..Brake System Downtown 350i Check and clear the ABS DTCs in the same manner as the fuel injection DTCs. Bosch ABS9m DTC LIST Code NO (Diagnostic Tool description (PDA) 3620A-LEB2-E00) 5013 Rear Inlet Valve malfunction (EV) 5014 Rear Outlet Valve malfunction (AV)
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10..Brake System Downtown 350i When using the DATA Analyze feature of the diagnostic tool with the ABS system the front and rear wheel speed sensors should show speed when the wheels are rotated. Inspect the wheel speed sensors, rotors, wires, and connectors if the speed doesn't show correctly.
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10..Brake System Downtown 350i ABS Unit Note the markings on the ABS unit for the brake Front (F) and Rear (R) brake hose positions. Do not attempt to disassemble the ABS unit. If the ABS unit must be replaced the new unit should come filled with brake fluid. Install the new component immediately so that the brake fluid doesn't drain out.
11.Steering Downtown 350i 11.Steering This chapter covers the location and servicing of the steering components for the KYMCO Downtown 350i model. Handlebar ..................11-2 Grips ....................11-8 Steering stem .................11-8 TROUBLESHOOTING Hard steering (heavy) • Excessively tightened steering stem top cone race •...
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11.Steering Downtown 350i Handlebar SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the handlebar covers. See the Handlebar Covers topic for more information. Remove the front cover. See the Front Cover topic for more information.
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11.Steering Downtown 350i Switch Housings and Throttle Remove the two right switch housing mounting screws with a #2 Phillips screwdriver. Disconnect the switch. Separate the switch housing from the handlebar. Disconnect the throttle cables and free the right switch housing from the handlebar.
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11.Steering Downtown 350i Remove the two left switch housing mounting screws with a #2 Phillips screwdriver. Disconnect the switch. Separate the left switch housing from the handlebar. 11-4...
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11.Steering Downtown 350i Handlebar Route the cables and lines from the handlebar cable guide. Hold the handlebar lock bolt with a 14 mm wrench and loosen the nut with a 17 mm socket. 11-5...
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11.Steering Downtown 350i Remove the handlebar lock nut and bolt. Remove the handlebar. The torque of installation. Torque Item lb-ft Handlebar Lock Nut 11-6...
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11.Steering Downtown 350i Grips If you plan to replace the grips you can slice them lengthwise with a razor blade and peel them off. To remove the grips without cutting them use a screwdriver to open a gap between the grip and the handlebar. Spray in contact cleaner to break up the grip cement.
If the movement is to tight or loose the steering stem adjusting nut may need to be adjusted. The KYMCO Downtown 350i uses ball bearings in the steering. Always replace the races at the same time as the bearings.
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11.Steering Downtown 350i A special lock nut wrench is needed to loosen the steering stem lock nut. Special Tool - Lock Nut Wrench: F00002 Slide the special tool over the steering stem and loosen the lock nut. Installation torque Torque...
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11.Steering Downtown 350i Remove the steering stem lock nut. Slide off the lock washer. Support the steering stem and loosen the steering stem adjusting nut. 11-10...
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11.Steering Downtown 350i Remove the steering stem adjusting nut. Remove the dust cover and grease seal. Lower the steering stem out of the frame. 11-11...
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11.Steering Downtown 350i Lift out the upper ball bearings. Slide the lower ball bearings up and off of the steering stem. Inspect the bearings and races for wear and damage. Replace them as needed. Use a chisel to remove the bottom bearing inner race and dust seal. Do not damage the steering stem.
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11.Steering Downtown 350i Use the special tools or a drift and hammer to drive out the bearing races in the steering head. Have the drift set against the lip of the race, and work around the race evenly to drive it out. Repeat the process with the remaining bearing race.
12.Front Suspension Downtown 350i 12.Front Suspension This chapter covers the location and servicing of the front fork components for the KYMCO Downtown 350i model. Front Fork Removal ...............12-2 Front Fork Installation ..............12-6 Fork Disassembly ................12-8 Fork Assembly ................12-17 TROUBLESHOOTING Soft front shock absorber •...
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12.Front Suspension Downtown 350i Front Fork Removal and Installation SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Remove the front cover. See the Front Cover topic for more information. Remove the front fender. See the Front Fender topic for more information.
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12.Front Suspension Downtown 350i Remove the two caliper mounting bolts with a 12 mm socket. And remove the front caliper. Remove the speedometer sensor mounting bolt with an 8 mm socket. And remove the speedometer sensor. 12-3...
12.Front Suspension Downtown 350i Remove the front wheel speed sensor from the bottom of the right fork leg. Remove the front brake caliper. See the Front Caliper topic for more information. Remove the front wheel. See the Front Wheel topic for more information.
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12.Front Suspension Downtown 350i Loosen the fork clamp pinch bolts with a 12 mm socket. The top bolts must be removed. Slide the forks legs down and out of the fork clamp using a twisting motion. To disassemble the forks see the Fork Disassembly topic for more information.
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12.Front Suspension Downtown 350i Installation Slide the fork legs up into fork clamp using a twisting motion. Install the fork legs so that the upper fork clamp bolt hole lines up with the groove on the inner fork tube. Insert the fork clamp upper bolt.
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12.Front Suspension Downtown 350i Install the speed sensor wire and front brake hose guide to the fork clamp. Insert the guide mounting bolt and tighten it to specification with an 8 mm socket. Torque Thread Item size (mm) kgf-m lb-ft Speed sensor cable 1.0-1.4...
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12.Front Suspension Downtown 350i Fork Disassembly SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Remove the front forks. See the Front Fork Removal and Installation topic for more information. Clean the outside of the forks before disassembly and inspect them for any cracks, dents or other damage.
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12.Front Suspension Downtown 350i Remove the rubber fork cap. Place the fork leg in a soft jawed vice. Push down on the top plug and remove the snap ring. 12-9...
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12.Front Suspension Downtown 350i Remove the top plug. Lift out the fork spring. Dump the fork oil into a suitable container. Pump the fork through its stroke several times to free as much oil as possible. Hold the fork inverted for several minutes to let the oil drain completely.
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12.Front Suspension Downtown 350i Use a flat blade screwdriver to pop the dust seal out of the fork slider. Take care to avoid scratching the fork tube. Use a small flat blade screwdriver to pry out the fork oil seal stopper ring. Take care to avoid scratching the fork tube.
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12.Front Suspension Downtown 350i Place the axle holder of the outer fork tube in a soft jawed vise. Insert an 8 mm Allen socket into the damper rod. Hold the damper rod and loosen the fork bottom bolt with an 8 mm Allen wrench.
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12.Front Suspension Downtown 350i Separate the inner and outer fork tubes by pulling them apart using a slide hammer motion. Remove the oil lock piece. The oil lock piece may come out with the damper rod in the inner fork tube or it may be left in the slider.
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12.Front Suspension Downtown 350i Inspect the oil seal and the bushing in the fork slider. Place a rag across the top of the fork slider and pry out the oil seal as shown. Remove the oil seal and spacer from the fork slider.
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12.Front Suspension Downtown 350i Inspection Inspect the top plug O-ring and replace it if needed. Insect the slider bushing and replace it as needed. 12-15...
12.Front Suspension Downtown 350i Inspect the fork springs for signs of fatigue. Replace the fork springs if they vary dramatically in length. Inspect the damper rod and seal. Replace the components as needed. Inspect the inner fork tube for bends and damage. Replace it as needed.
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12.Front Suspension Downtown 350i Fork Assembly SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Clean all of the fork components with aerosol brake cleaner and a lint free cloth. Coat the bushing and seals with fork oil before installation.
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12.Front Suspension Downtown 350i Place the spacer into the fork slider. Insert the inner fork tube into the outer fork tube. Place a new sealing washer on the fork bottom bolt. Insert the fork bottom bolt into the bottom the fork slider and thread it into the damper rod.
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12.Front Suspension Downtown 350i Place the axle holder of the outer fork tube in a soft jawed vise. Insert an 8 mm Allen socket into the damper rod. Hold the damper rod and tighten the fork bottom bolt securely with an 8 mm Allen wrench.
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12.Front Suspension Downtown 350i Insert the stopper ring into its groove. Install the dust seal securely into the outer fork tube. Compress the fork tube all the way. Fill the fork tube with the specified quantity of fork oil 185 cc or 6.26 US oz. Use fork oil type SS#8 (10W).
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12.Front Suspension Downtown 350i Pump the fork slowly through its stroke several times to release any trapped air. Fully extend the fork and insert the fork spring with its tightly coiled end facing down towards the axle. Lubricate the top plug O-ring with fresh fork oil and insert the plug into the top of the inner fork tube as shown.
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12.Front Suspension Downtown 350i Install the rubber fork cap. Fit the fork protectors into place so that they face forward. Install the front fork. See the Front Fork Removal and Installation topic for more information. 12-22...
13.Rear Suspension Downtown 350i 13.Rear Suspension This chapter provides information on the rear suspension components of the KYMCO Downtown 350i model. Shock Absorbers ................13-2 Rear Fork ..................13-8 TROUBLESHOOTING Soft rear shock absorber • Weak shock absorber spring • Damper oil leaks...
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13.Rear Suspension Downtown 350i Shock Absorbers SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Pre-Load Setting Each shock absorber on the scooter has 5 spring preload adjustment positions for different load or riding conditions. 13-2...
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13.Rear Suspension Downtown 350i Position 1 is for light loads and smooth road conditions. Position 3 to 5 increase spring preload for stiffer rear suspension and can be used when the scooters heavily loaded. Be certain to adjust both shock absorbers to the same spring preload positions.
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13.Rear Suspension Downtown 350i Removal Place the vehicle on its center stand. Remove the seat. See the Seat topic for more information. Remove the luggage box. See the Luggage Box topic for more information. Remove the rear carrier. See the Rear Carrier topic for more information.
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13.Rear Suspension Downtown 350i Remove the upper shock absorber mounting bolt with a 12 mm socket. Free the shock absorber from the frame. Remove the left shock absorber in the same manner as the right. Inspect the shock absorbers for wear and damage. Replace the shock absorbers as needed.
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13.Rear Suspension Downtown 350i Installation Fit the shock absorber into place. Make sure the preload arrow indicator faces out from the lower mount. Install the upper shock absorber mounting bolt and torque it to specification with a 12 mm socket.
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13.Rear Suspension Downtown 350i Install the lower shock absorber mounting bolt and torque it to specification with a 12 mm socket. Torque Item kgf-m lb-ft Shock absorber mounting bolt 28.93 Install the other shock absorber in the same manner. Install the rear carrier. See the Rear Carrier topic for more information.
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13.Rear Suspension Downtown 350i Rear Fork SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Place the vehicle on its center stand. Remove the muffler. See the Exhaust System topic for more information. Remove the rear fender. See the Rear Fender topic for more information.
13.Rear Suspension Downtown 350i Hold the rear brake to keep the rear wheel from turning. Remove the rear axle nut with a 24 mm socket. Remove the rear brake caliper. See the Rear Brake Caliper topic for more information. 13-9...
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13.Rear Suspension Downtown 350i Remove the two rear fork bolts with a 14 mm socket. Slide the rear fork out and remove it from the right side of the vehicle. Inspect the rear fork for damage and replace it as needed.
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13.Rear Suspension Downtown 350i Installation Fit the rear fork into place. 13-11...
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13.Rear Suspension Downtown 350i Install the two rear fork mounting bolts and tighten them securely with a 14 mm socket. Install the rear axle nut and tighten it to specification with a 24 mm socket. Thread Torque Item Remarks kgf-m...
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13.Rear Suspension Downtown 350i Install the lower shock absorber mounting bolt and torque it to specification with a 12 mm socket. Torque Item kgf-m lb-ft Shock absorber mounting bolt 28.93 Install the muffler. See the Exhaust System topic for more information.
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14.Wheels Downtown 350i 14.Wheels This chapter covers the location and servicing of the wheels for the KYMCO Downtown 350i model. Bearing Replacement ..............14-2 Front Wheel ..................14-6 Rear Wheel ..................14-11 Wheel Inspection ................14-19 Wheel Specifications ..............14-21 Troubleshooting Front wheel wobbling • Bent rim •...
14.Wheels Downtown 350i Wheel Bearing Replacement SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Replace bearings as a set, and do not reuse old bearings. Place the new bearings in the freezer about an hour before you plan to install them.
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14.Wheels Downtown 350i Remove one of the bearings with a bearing puller. Special Tools- Bearing Puller: E00037 Remove the distance collar. Repeat the procedure and remove the other bearing and seal. The seal should be replaced with a new item.
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14.Wheels Downtown 350i Heat the bearing area of the wheel with a heat gun, take the bearing out of the freezer and install it. You can use a bearing installer tool or a socket with the same outside diameter as the bearing. Make sure the bearing is fully seated and the marked side is facing out.
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14.Wheels Downtown 350i Drive in the other bearing. The bearing should fit against the distance collar. Do not continue to force the bearing in or the distance collar will begin to push the right bearing back out. Apply grease to the lips of the dust seals. Drive in new dust seals.
14.Wheels Downtown 350i Front Wheel SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Removal Loosen the front axle pinch bolt with a 6 mm Allen. Loosen the front axle with an 8 mm Allen socket. 14-6...
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14.Wheels Downtown 350i Lift the front end of the vehicle with a suitable stand or jack so that the front wheel comes off of the ground. Support the front wheel and slide the front axle out from the left side.
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14.Wheels Downtown 350i Remove the collars from each side of the wheel. Inspect the bearing seals and the O-rings seals on the collars. Replace the seals if they are in poor condition. Inspect the wheels and axle. See the Wheel Inspection topic for more information.
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14.Wheels Downtown 350i Installation Apply grease to the lips of the dust seals and collar O-rings. Insert the collars into the hub as shown. Make sure the tire direction of rotation marker is correct. Slide the front wheel into the fork. Fit the brake disc between the brake pads in the front caliper.
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14.Wheels Downtown 350i Torque the axle to specification with an 8 mm Allen. Torque Thread Item size (mm) kgf-m lb-ft Front axle 1.5-2.5 10.84-18.08 Tighten the front axle pinch bolt securely with a 6 mm Allen. Pump the front brake lever to establish pressure and to seat the pads against the disc.
14.Wheels Downtown 350i Rear Wheel SAFETY FIRST: Protective gloves and eyewear are recommended at this point. • When performing the services stated in this section, the engine and exhaust muffler must be cold to avoid scalding. • During servicing, keep oil or grease off the brake pads and brake disk.
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14.Wheels Downtown 350i Free the lower mount of the rear shock. Hold the rear brake to keep the rear wheel from turning. Remove the rear axle nut with a 24 mm socket. Remove the rear brake caliper. See the Rear Brake Caliper topic for more information.
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14.Wheels Downtown 350i Remove the rear brake caliper. See the Rear Brake Caliper topic for more information. Remove the two rear fork bolts with a 14 mm socket. 14-13...
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14.Wheels Downtown 350i Slide the rear fork out and remove it from the right side of the vehicle. To remove the rear wheel support the right rear shock absorber so that it is out of the way or remove it.
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14.Wheels Downtown 350i Installation Line up the splines on the rear wheel with those of the rear axle. Slide the rear wheel on to the axle so that the brake disc sits on the right side. Install the right shock absorber if it was removed. Install the upper mounting bolt and tighten it to specification with a 12 mm socket.
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14.Wheels Downtown 350i Fit the rear fork into place. Install the two rear fork mounting bolts and tighten them securely with a 14 mm socket. 14-16...
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14.Wheels Downtown 350i Install the rear axle nut and tighten it to specification with a 24 mm socket. Torque Thread Item Remarks size (mm) kgf-m lb-ft Rear axle nut 11-13 79.56-94.03 U-nut Fit the shock absorber into place. Make sure the preload arrow indicator faces out from the lower mount.
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14.Wheels Downtown 350i Install the upper shock absorber mounting bolt and torque it to specification with a 12 mm socket. Torque Item kgf-m lb-ft Shock absorber mounting bolt 28.93 Install the lower shock absorber mounting bolt and torque it to specification with a 12 mm socket.
14.Wheels Downtown 350i Wheel Inspection SAFETY FIRST: Protective gloves and eyewear are recommended at this point. Turn the inner race of each bearing with your finger to see if they turn smoothly and quietly. Also check if the outer race fits tightly in the hub.
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14.Wheels Downtown 350i Check for radial hop. The service limit is 2.0 mm (0.08 in) or less. Check the front axle runout. The axle runout specification is half of the total indicator reading. Replace the axle if the measurement exceeds 0.2 mm or 0.008 in.
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14.Wheels Downtown 350i Axle/Brakes/Wheels Item Standard mm (in) Service Limit 0.2 mm — Axle shaft runout (0.008 in) 3.8 - 4.2 0.3 mm Brake disk thickness (front) (0.15 - 0.165) (0.012 in) — Brake disk thickness (rear) (0.2) — Brake disk runout 0.4 mm...
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Memo Reference Data ECU No ACD5 Hardware Ver Software Ver C-2441 Calibration Ver ACD5-AA Model Name KYMCO-LEA7 Active Occurred History DTC Number Full Throttle: >93% Throttle Position(%) < 1.00% Full Throttle Voltage: 3.5~3.8V 0.60±0.1 V Throttle Position Voltage (V) Engine Temp.(°C) Environ.temp ±...
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OWNTOWN 350i Memo 3.5~3.8V up at an elevation of 1000 re pressure goes down 12kpa. e Temp. > 80°C 可能會高於2.8ms(常溫初始動約3.5ms) e Temp. > 80°C 可能會高於2.8ms(常溫初始動約3.5ms)
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