Yamaha F25C Service Manual
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Yamaha F25C Service Manual

Yamaha F25C Service Manual

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F25C
SERVICE MANUAL
290539
6D5-28197-5F-11

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Summary of Contents for Yamaha F25C

  • Page 1 F25C SERVICE MANUAL 290539 6D5-28197-5F-11...
  • Page 2 NOTICE This manual has been prepared by Yamaha primarily for use by Yamaha dealers and their trained mechanics when performing maintenance procedures and repairs to Yamaha equipment. It has been written to suit the needs of persons who have a basic understanding of the mechanical and electrical concepts and procedures inherent in the work, for without such knowledge attempted repairs or service to the equipment could render it unsafe or unfit for use.

  • Page 3: Table Of Contents

    Contents General information INFO Specifications SPEC Periodic checks and adjustments Fuel system FUEL Power unit POWR Lower unit LOWR Bracket unit BRKT – Electrical systems ELEC Troubleshooting TRBL SHTG Index...

  • Page 5: General Information

    INFO General information How to use this manual ................. 1-1 Manual format.................... 1-1 Symbols..................... 1-2 Safety while working..................1-3 Fire prevention................... 1-3 Ventilation....................1-3 Self-protection ................... 1-3 Parts, lubricants, and sealants ..............1-3 Good working practices ................1-4 Disassembly and assembly ............... 1-4 Identification....................1-5 Applicable models ..................1-5 Serial number ....................

  • Page 6: How To Use This Manual

    INFO General information How to use this manual Manual format The format of this manual has been designed to make service procedures clear and easy to under- stand. Use the information below as a guide for effective and quality service. 1 Parts are shown and detailed in an exploded diagram and are listed in the components list.

  • Page 7: Symbols

    7 Apply Yamaha 4-stroke motor oil A Apply corrosion resistant grease 8 Apply gear oil (Yamaha grease D) 9 Apply water resistant grease (Yamaha grease A) B Apply low temperature resistant grease 0 Apply molybdenum disulfide grease (Yamaha grease C)

  • Page 8: Safety While Working

    Parts, lubricants, and sealants Use only genuine Yamaha parts, lubricants, and sealants or those recommended by Yamaha, when servicing or repairing the out- board motor. Ventilation Gasoline vapor and exhaust gas are heavier than air and extremely poisonous.

  • Page 9: Good Working Practices

    Safety while working Disassembly and assembly 6. Keep a supply of clean, lint-free cloths for wiping up spills, etc. 1. Use compressed air to remove dust and dirt during disassembly. Good working practices Special service tools 2. Apply engine oil to the contact surfaces Use the recommended special service tools of moving parts before assembly.

  • Page 10: Identification

    INFO General information Identification Propeller selection Applicable models The performance of a boat and outboard motor will be critically affected by the size This manual covers the following models. and type of propeller you choose. Propellers Applicable models greatly affect boat speed, acceleration, engine life, fuel economy, and even boating F25CMH, F25CM and steering capabilities.

  • Page 11: Selection

    Identification / Propeller selection / Predelivery checks a Propeller diameter (in inches) b Propeller pitch (in inches) CAUTION: c Propeller type (propeller mark) This is a 4-stroke engine. Never use pre- mixed fuel. Selection When the engine speed is at the full throttle operating range (5,000–6,000 r/min), the Checking the engine oil level ideal propeller for the boat is one that pro-...

  • Page 12: Checking The Outboard Motor Mounting Height

    INFO General information Checking the outboard motor mounting height 1. Check that the anti-cavitation plate is between the bottom of the boat and a maximum of 25 mm (1 in) a below it. If the mounting height is too high, cavita- tion will occur and propulsion will be reduced.

  • Page 13: Checking The Steering System

    Predelivery checks Checking the steering system Checking the gear shift and throttle 1. Check the steering friction for proper operation adjustment. 1. Check that the gear shift operates smoothly when the remote control lever or shift lever is shifted from neutral to for- ward or reverse.

  • Page 14: Checking The Engine Stop Lanyard Switch

    INFO General information Checking the engine stop lanyard Checking the cooling water pilot switch holes 1. Check that the engine turns off when the 1. Check that cooling water is discharged engine stop lanyard switch is pushed or from the cooling water pilot holes. the engine stop lanyard is pulled from the engine stop lanyard switch.

  • Page 15: Break-In

    Predelivery checks Break-in During the test run, perform the break-in operation in the following three stages. 1. One hour a at 2,000 r/min or at approxi- mately half throttle 2. One hour b at 3,000 r/min or 3/4 throttle and 1 minute out of every 10 at full throt- 3.
  • Page 16 INFO General information — MEMO — 1-11 6D55F11...

  • Page 17: Specifications

    SPEC Specifications General specifications................... 2-1 Maintenance specification ................2-3 Power unit....................2-3 Lower unit ....................2-7 Electrical ....................2-7 Dimensions....................2-9 Tightening torques..................2-11 Specified torques..................2-11 General torques..................2-13 6D55F11...

  • Page 18: General Specifications

    SPEC Specifications General specifications Model Item Unit F25CMH F25CM Dimension Overall length mm (in) 1,151 (45.3) 703 (27.7) Overall width mm (in) 430 (16.9) 376 (14.8) Overall height mm (in) 1,148 (45.2) — mm (in) 1,275 (50.2) Boat transom height mm (in) 381 (15.0) —...
  • Page 19 General specifications Model Item Unit F25CMH F25CM Fuel and oil Fuel type Regular unleaded gasoline (*1) Fuel minimum rating Engine oil 4-stroke motor oil Engine oil grade SE, SF, SG, SH, or SJ 10W-30 or 10W-40 Engine oil quantity (without oil filter replacement) L (US qt, 1.7 (1.8, 1.5) lmp qt)

  • Page 20: Maintenance Specification

    SPEC Specifications Maintenance specification Power unit Model Item Unit F25CMH F25CM Power unit Minimum compression 810 (8.1, 115) (*1) pressure (kgf/cm , psi) (*2) Lubrication oil pressure 80 (0.8, 11) at engine idle speed (kgf/cm , psi) Cylinder heads Warpage limit mm (in) 0.10 (0.0039) (lines indicate straightedge...
  • Page 21 Maintenance specification Model Item Unit F25CMH F25CM Piston rings Top ring Dimension B mm (in) 1.17–1.19 (0.0461–0.0469) Dimension T mm (in) 2.25–2.45 (0.0885–0.0965) End gap mm (in) 0.15–0.30 (0.0059–0.0118) Side clearance mm (in) 0.02–0.06 (0.0008–0.0024) Oversize diameter mm (in) 65.250 (2.5689) mm (in) 65.500 (2.5787) 2nd ring...
  • Page 22 SPEC Specifications Model Item Unit F25CMH F25CM Valves Valve clearance (cold) Intake mm (in) 0.15–0.25 (0.006–0.010) Exhaust mm (in) 0.25–0.35 (0.010–0.014) Head diameter (A) Intake mm (in) 31.90–32.10 (1.256–1.264) Exhaust mm (in) 25.90–26.10 (1.020–1.028) Face width (B) Intake mm (in) 1.84–2.97 (0.072–0.117) Exhaust mm (in)
  • Page 23 Maintenance specification Model Item Unit F25CMH F25CM Crankcase Crankshaft main journal oil mm (in) 0.012–0.044 (0.0005–0.0017) clearance Crankcase main journal bearing thickness Blue mm (in) 1.498–1.502 (0.0590–0.0591) Black mm (in) 1.494–1.498 (0.0588–0.0590) Brown mm (in) 1.490–1.494 (0.0587–0.0588) Oil pump Type Trochoid Outer rotor-to-housing mm (in)

  • Page 24: Lower Unit

    SPEC Specifications Lower unit Model Item Unit F25CMH F25CM Gear backlash Pinion-to-forward gear mm (in) 0.30–0.72 (0.0118–0.0283) Pinion-to-reverse gear mm (in) 0.92–1.65 (0.0362–0.0650) Pinion shims 0.7, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6 Forward gear shims 1.0, 1.1, 1.2, 1.3, 1.4 Reverse gear shims 1.0, 1.1, 1.2, 1.3 Electrical...
  • Page 25 Maintenance specification Model Item Unit F25CMH F25CM Charge coil output peak voltage (G/W – W/G) at cranking (unloaded) 170.0 at cranking (loaded) 130.0 at 1,500 r/min (loaded) 140.0 at 3,500 r/min (loaded) 140.0 (*1) Charge coil resistance (G/W – W/G) Ω...

  • Page 26: Dimensions

    SPEC Specifications Dimensions Exterior * Tiller handle model only mm (in) 572 (22.5)* S: 763 (30.0) 363 (14.3)* L: 877 (34.5) 296 (11.7)* 580 (22.8) 190 (7.5)* 65 (2.6) S: 43 (1.7) L: 34 (1.3) 432 (17.0) S6D52010 6D55F11...
  • Page 27 Maintenance specification Clamp bracket 2-10 6D55F11...

  • Page 28: Tightening Torques

    SPEC Specifications Tightening torques Specified torques Tightening torques Part to be tightened Thread size N·m kgf·m ft·lb Fuel system Fuel pump mounting bolt Fuel pump screw Carburetor bracket bolt Throttle link rod screw Power unit Power unit mounting bolt 15.5 Apron bolt Start-in-gear protection cable bolt Manual starter roller bolt...
  • Page 29 Tightening torques Tightening torques Part to be tightened Thread size N·m kgf·m ft·lb Lower unit Gear oil drain screw — Gear oil check screw — Lower case mounting bolt 27.3 Cooling water inlet cover screw Propeller nut 25.1 Propeller shaft housing bolt Pinion nut 36.9 Bracket unit...

  • Page 30: General Torques

    SPEC Specifications General torques This chart specifies tightening torques for standard fasteners with a standard ISO thread pitch. Tightening torque specifications for special components or assemblies are provided in applicable sections of this man- ual. To avoid warpage, tighten multi-fastener assemblies in a crisscross fashion and pro- gressive stages until the specified torque is reached.
  • Page 31 Periodic checks and adjustments Special service tools ..................3-1 Maintenance interval chart................3-2 Top cowling ....................3-3 Checking the top cowling................3-3 Fuel system ....................3-3 Checking the fuel joint and fuel hoses (fuel joint-to-carburetor) ....3-3 Checking the fuel filter ................3-3 Power unit.......................

  • Page 32: Chk Adj

    Periodic checks and adjustments Special service tools Oil filter wrench 90890-01426 Digital tachometer 90890-06760 Timing light 90890-03141 Leakage tester 90890-06840 6D55F11...

  • Page 33: Maintenance Interval Chart

    Cooling water passages Clean Top cowling Check Fuel filter (can be disassembled) Check/replace Fuel system Check Fuel tank Check/clean (Yamaha portable tank) Gear oil Change Lubrication points Lubricate Engine idle speed Check/adjust (carburetor models) Propeller and cotter pin Check/replace Shift link/shift cable...

  • Page 34: Top Cowling

    Periodic checks and adjustments Top cowling Checking the top cowling 1. Check the fitting by pushing the cowling with both hands. Adjust if necessary. Fuel system Checking the fuel joint and fuel hoses (fuel joint-to-carburetor) S6D53010 1. Check the fuel hose connections and fuel 2.

  • Page 35: Power Unit

    Top cowling / Fuel system / Power unit NOTE: Be sure not to spill any fuel when removing the fuel filter cup. Power unit Checking the engine oil 1. Place the outboard motor in an upright position. 2. Remove the engine oil dipstick, wipe it 3.

  • Page 36: Replacing The Oil Filter

    Periodic checks and adjustments 7. Turn the engine off, and then check the Oil filter: oil level and correct it if necessary. 18 N·m (1.8 kgf·m, 13.3 ft·lb) Replacing the oil filter 1. Drain the engine oil. 5. Pour the specified amount of the recom- mended engine oil into the oil filler hole.

  • Page 37: Checking The Spark Plugs

    Power unit 5. Install the spark plugs, tighten them fin- NOTE: ger tight, then to the specified torque The valve system of this model will not be using a spark plug wrench. damaged even if the timing belt breaks. Spark plug: 17 N·m (1.7 kgf·m, 12.5 ft·lb) Timing belt slack a: Within 13 mm (0.5 in)

  • Page 38: Checking The Cooling Water Passage

    Periodic checks and adjustments 4. Check the thermostat valve opening at 3. Check for water flow at the cooling water specified water temperatures. pilot holes. If there is no water flow, Replace if out of specification. check the cooling water passages inside the outboard motor.

  • Page 39: Adjusting The Throttle Cables (Tiller Handle Model)

    Power unit / Control system 5. Operate the throttle cam to check that the throttle valve fully opens and fully closes. Adjusting the throttle cables (tiller handle model) 1. Turn the throttle grip to the fully open position. S6D53210 2. Loosen the locknut 1, and then turn the adjusting nut 2 to adjust the throttle Adjusting the throttle cable cable 3.

  • Page 40: Checking The Gear Shift Operation (Tiller Handle Model)

    Periodic checks and adjustments 5. Check the throttle cable for smooth oper- ation and, if necessary, repeat steps 1–4. Checking the gear shift operation (tiller handle model) 1. Check that the gear shift operates smoothly when shifting it from neutral to forward or reverse.

  • Page 41: Checking The Engine Idle Speed

    Control system 3. Turn the throttle stop screw 2 in direc- NOTE: tion a or b until the specified engine If the starter rope cannot be pulled out, the idle speed is obtained. start-in-gear protection is working correctly. 3. Shift the remote control lever or shift lever to neutral.

  • Page 42: Chk Adj

    Periodic checks and adjustments 4. Check that the a is specified timing on the flywheel magnet. Lower unit Checking the gear oil level Ignition timing at engine idle speed: 1. Fully tilt the outboard motor down. BTDC 8.5° 2. Remove the check screw 1, and then Bracket check the gear oil level in the lower case.

  • Page 43: Changing The Gear Oil

    Control system / Bracket / Lower unit Changing the gear oil Checking the lower unit for air 1. Tilt the outboard motor up slightly. leakage 1. Remove the check screw 1, and then 2. Place a drain pan under the drain screw install the special service tool.

  • Page 44: General

    Periodic checks and adjustments General Checking the anodes 1. Check the anodes for scales, grease, or oil. Clean if necessary. S6D53240 È CAUTION: Do not oil, grease, or paint the anodes, otherwise they will be ineffective. S6D53290 È Tiller handle model 2.

  • Page 45: Fuel

    FUEL Fuel system Special service tools ..................4-1 Hose routing ....................4-2 Fuel hoses and fuel filter................4-3 Fuel pump ....................... 4-4 Checking the fuel pump................4-5 Disassembling the fuel pump ..............4-5 Checking the diaphragms and valves............4-6 Assembling the fuel pump ................. 4-6 Checking the fuel joint ................

  • Page 46: Fuel System

    FUEL Fuel system Special service tools Vacuum/pressure pump gauge set 90890-06756 6D55F11...

  • Page 47: Hose Routing

    Special service tools / Hose routing Hose routing S6D54010 1 Blowby hoses 2 Fuel hose (fuel joint-to-fuel filter) 3 Fuel hose (fuel filter-to-fuel pump) 4 Fuel hose (fuel pump-to-carburetor) 5 Pilot water hose 6D55F11...

  • Page 48: Fuel Hoses And Fuel Filter

    FUEL Fuel system Fuel hoses and fuel filter Part name Q’ty Remarks Fuel joint M6 × 25 mm Bolt Fuel hose M8 × 14 mm Bolt Bracket Fuel filter Fuel filter element O-ring Not reusable Fuel hose Fuel hose Fuel pump O-ring Not reusable Bracket...

  • Page 49: Fuel Pump

    Fuel hoses and fuel filter / Fuel pump Fuel pump Part name Q’ty Remarks ø5 × 43 mm Screw Cover Gasket Not reusable Diaphragm Not reusable Fuel pump body 2 assembly Plunger Spring Fuel pump body 1 Spring Diaphragm 6D55F11...

  • Page 50: Checking The Fuel Pump

    FUEL Fuel system Checking the fuel pump 6. Apply the specified positive pressure and check that there is no air leakage. Disas- 1. Place a drain pan under the fuel hose semble the fuel pump if necessary. connections, and then disconnect the fuel hoses from the fuel pump.

  • Page 51: Checking The Diaphragms And Valves

    Fuel pump 3. Turn fuel pump body 1 2 approximately 90°, and then push down on the plunger several times to make sure that the pin does not come out. 3. Slowly let up on the plunger and dia- phragm, and then remove them. Checking the diaphragms and valves 1.

  • Page 52: Checking The Fuel Joint

    FUEL Fuel system Checking the fuel joint 1. Visually check the fuel hose connector for cracks or damage. 2. Connect the special service tool at the outlet of fuel hose connector. 3. Apply the specified pressure to check that the pressure is maintained for 10 seconds.

  • Page 53: Carburetor Unit

    Fuel pump / Carburetor unit Carburetor unit Part name Q’ty Remarks M6 × 25 mm Bolt Fuel hose Plastic tie Not reusable Blowby hose M6 × 100 mm Bolt Intake silencer Joint Seal O-ring Not reusable Plate Bracket O-ring Not reusable Spacer Carburetor 6D55F11...

  • Page 54: Carburetor

    FUEL Fuel system Carburetor Part name Q’ty Remarks Throttle link rod ø4 × 5 mm Screw ø4 × 10 mm Screw Retainer Prime Start O-ring Not reusable ø4 × 10 mm Screw Cover Gasket Not reusable Throttle stop screw Spring Pilot screw O-ring Not reusable...
  • Page 55 Carburetor Part name Q’ty Remarks Carburetor body Float chamber Gasket Not reusable Plunger rod Plunger Spring Circlip Ball Drain screw ø4 × 13 mm Screw ø4 × 7 mm Screw Float Needle valve Main jet Main nozzle Plug Pilot jet 4-10 6D55F11...

  • Page 56: Removing The Carburetor

    FUEL Fuel system Removing the carburetor 1. Remove the manual starter. 2. Disconnect the throttle link rod and Prime Start connectors. 3. Disconnect the fuel hose. 4. Disconnect the blowby hose 1. CAUTION: • Direct the compressed air downward, otherwise cleaning solvent may be blown into your eyes or small parts of the carburetor may be blown off.

  • Page 57: Checking The Prime Start

    Carburetor Prime Start plunger extended length a (reference data): 10.7–15.4 mm (0.42–0.61 in) Time (min) Length (mm [in]) 10.7 (0.42) 12.6 (0.50) 14.1 (0.56) 14.8 (0.58) 15.3 (0.60) NOTE: • The float should be resting on the needle 15.4 (0.61) valve 1, but not compressing it.

  • Page 58: Adjusting The Throttle Stop Screw

    FUEL Fuel system 2. Install the needle valve 5, float 6, float pin 7, and screw 8 as shown, and then the check the float for smooth operation. NOTE: For remote control models, the throttle cam S6D54120 cannot be turned unless the remote control lever is shifted to forward.
  • Page 59 Carburetor NOTE: • To increase the idle speed, turn the throttle stop screw in direction a. • To decrease the idle speed, turn the throttle stop screw in direction b. Engine idle speed: 925–1,025 r/min 4-14 6D55F11...

  • Page 60: Powr

    POWR Power unit Special service tools ..................5-1 Power unit....................... 5-3 Checking the compression pressure ............5-3 Checking the oil pressure ................5-3 Checking the valve clearance..............5-4 Disassembling the manual starter ............5-13 Checking the spiral spring ............... 5-13 Measuring the starter rope ..............5-13 Assembling the manual starter ..............5-13 Installing the starter rope .................5-14 Removing the timing belt and sprockets..........
  • Page 61 Cylinder block ....................5-33 Disassembling the cylinder block ............5-36 Checking the balancer................5-37 Checking the piston diameter ..............5-37 Checking the cylinder bore ..............5-37 Checking the piston clearance ..............5-38 Checking the piston rings ................5-38 Checking the piston ring grooves ............5-39 Checking the piston ring side clearance..........

  • Page 62: Power Unit

    POWR Power unit Special service tools Compression gauge Valve spring compressor attachment 90890-03160 90890-06320 Flywheel holder Valve guide remover/installer 90890-06522 90890-06801 Universal clutch holder Valve guide reamer 90890-04086 90890-06804 Flywheel puller Valve seat cutter holder 90890-06521 90890-06316 Valve spring compressor Valve seat cutter 90890-04019 90890-06312, 90890-06315, 90890-06323,...
  • Page 63 Special service tools Bearing outer race attachment 90890-06626 Driver rod LS 90890-06606 Oil filter wrench 90890-01426 Piston slider 90890-06529 6D55F11...

  • Page 64: Power Unit

    POWR Power unit Power unit 5. If the compression pressure is below specification and the compression pres- Checking the compression pressure sure for each cylinder is unbalanced, add 1. Start the engine, warm it up for 5 min- a small amount of engine oil to the cylin- utes, and then turn it off.

  • Page 65: Checking The Valve Clearance

    Power unit Checking the valve clearance 7. Check the intake and exhaust valve clearances for cylinder #2. Adjust if out of 1. Remove the manual starter. specification. 2. Remove the fuel pump 1. 3. Disconnect the ignition coil connectors and spark plug caps 2 and remove the spark plugs and cylinder head cover 3.
  • Page 66 POWR Power unit 8. Loosen the rocker arm locknut 4, and then turn the adjusting screw 5 until the specified valve clearance is obtained. S6D55100 NOTE: • To decrease the valve clearance, turn the adjusting screw in direction f. • To increase the valve clearance, turn the adjusting screw in direction g.
  • Page 67 Power unit Part name Q’ty Remarks M5 × 13 mm Bolt Washer Clip Start-in-gear protection cable M6 × 25 mm Bolt Manual starter M6 × 12 mm Bolt Power unit Dipstick Dowel M6 × 14 mm Bolt Gasket Not reusable M8 ×...
  • Page 68 POWR Power unit Part name Q’ty Remarks M8 × 12 mm Bolt Starter pulley Washer Flywheel magnet Spacer M5 × 25 mm Bolt Stator coil Woodruff key Woodruff key Drive sprocket Driven sprocket Pulser coil M5 × 16 mm Bolt Washer M10 ×...
  • Page 69 Power unit m (0.5 kgf m, 3.7 ft m (0.8 kgf m, 5.9 ft • • • • • • 23 24 m (0.5 kgf m, 3.7 ft • • • S6D55040 Part name Q’ty Remarks Ignition coil M6 × 30 mm Bolt Holder Grommet...
  • Page 70 POWR Power unit m (0.5 kgf m, 3.7 ft m (0.8 kgf m, 5.9 ft • • • • • • 23 24 m (0.5 kgf m, 3.7 ft • • • S6D55040 Part name Q’ty Remarks CDI unit Bracket M5 ×...
  • Page 71 Power unit Part name Q’ty Remarks M6 × 55 mm Bolt Washer Throttle control lever Spacer Throttle cam M6 × 10 mm Bolt Bracket M6 × 25 mm, Remote control model Bolt Washer Remote control model Shift link lever Remote control model Collar Remote control model Shift link rod...
  • Page 72 POWR Power unit m (0.8 kgf m, 5.9 ft • • • m (0.3 kgf m, 2.2 ft • • • 15 N m (1.5 kgf m, 11.1 ft • • • S6D55020 Part name Q’ty Remarks M6 × 30 mm Bolt Washer Roller...
  • Page 73 Power unit m (0.8 kgf m, 5.9 ft • • • m (0.3 kgf m, 2.2 ft • • • 15 N m (1.5 kgf m, 11.1 ft • • • S6D55020 Part name Q’ty Remarks Bolt Drive plate Spring Sheave drum Cartridge spring Spring washer...

  • Page 74: Disassembling The Manual Starter

    POWR Power unit Disassembling the manual starter Measuring the starter rope 1. Remove the lock cam retainer, and then 1. Measure the starter rope length. Replace remove the lock cam base plate 1 and if the length is out of specification. lock cam 2.

  • Page 75: Installing The Starter Rope

    Power unit 3. Install the drive pawls 4. 3. Turn the sheave drum clockwise until the rope hole a and manual starter roller b 4. Install the spring 5 and drive plate 6, are aligned. Hold the sheave drum in this and then tighten the bolt 7 to the speci- position.

  • Page 76: Removing The Timing Belt And Sprockets

    POWR Power unit 5. Pull the manual starter handle several times to check that the sheave drum turns smoothly and to check the starter rope for slack. Repeat steps 2–4 if nec- essary. NOTE: When checking the manual starter operation, pull the manual starter handle while pushing the start-in-gear protection lock cam so that it 3.
  • Page 77 Power unit 6. Disconnect the charge coil connectors CAUTION: and power bobbin connectors, and remove the stator coil 2. Apply force in the direction of the arrows shown to prevent the flywheel holder from slipping off easily. Flywheel holder: 90890-06522 5.

  • Page 78: Checking The Timing Belt And Sprockets

    POWR Power unit Checking the timing belt and sprockets 1. Check the interior and exterior of the tim- ing belt for cracks, damage, or wear. Replace if necessary. 2. Check the drive sprocket and driven sprockets for cracks, damage, or wear. Replace if necessary.

  • Page 79: Removing The Power Unit

    Power unit NOTE: Do not turn the drive sprocket counterclock- wise, otherwise the valve system may be damaged. 6. Install the stator coil, and connect the charge coil connectors and power bobbin connectors. 7. Install the Woodruff key, then the fly- Universal clutch holder: wheel magnet.
  • Page 80 POWR Power unit 5. Remove the apron 1, and then remove the power unit by removing the bolts 2. 6. Remove the flywheel magnet, then the woodruff key. 5-19 6D55F11...

  • Page 81: Cylinder Head

    Power unit / Cylinder head Cylinder head Part name Q’ty Remarks Cylinder head Gasket Not reusable Dowel M9 × 95 mm Bolt M6 × 25 mm Bolt O-ring Not reusable O-ring Not reusable O-ring Not reusable Oil pump assembly M6 × 35 mm Bolt Gasket Not reusable...
  • Page 82 POWR Power unit Part name Q’ty Remarks Cover M5 × 12 mm Bolt Anode Grommet Spark plug 5-21 6D55F11...
  • Page 83 Cylinder head Part name Q’ty Remarks Exhaust valve Intake valve Valve spring seat Valve seal Not reusable Valve spring Valve spring retainer Valve cotter Rocker arm assembly Rocker arm retainer M8 × 30 mm Bolt Stopper guide Tensioner Rocker arm shaft Retaining bolt Gasket Not reusable...

  • Page 84: Removing The Cylinder Head

    POWR Power unit Removing the cylinder head 1. Remove the cylinder head cover. 2. Remove the cylinder head bolts in the sequence shown. & ± S6D55450 6. Remove the intake and exhaust valves. CAUTION: Do not scratch or damage the mating sur- faces of the cylinder head and cylinder block.

  • Page 85: Checking The Valve Springs

    Cylinder head Checking the valve springs Valve margin thickness a: 1. Measure the valve spring free length a. Intake: 0.8 mm (0.0315 in) Replace if below specification. Exhaust: 0.9 mm (0.0354 in) 3. Measure the valve stem diameter b. Replace if out of specification. Valve spring free length a: 39.85 mm (1.5689 in) 2.

  • Page 86: Checking The Valve Guides

    POWR Power unit Checking the valve guides Valve guide remover/installer: NOTE: 90890-06801 Before checking the valve guide make sure that the valve stem diameter is within specifi- 2. Install a new valve guide 2 by striking cation. the special service tool from the cam- shaft side until the valve guide clip 3 1.

  • Page 87: Checking The Valve Seat

    Cylinder head 4. Measure the valve guide inside diameter. Valve guide inside diameter: Intake and exhaust: 5.500–5.512 mm (0.2165–0.2170 in) Checking the valve seat 1. Eliminate carbon deposits from the valve with a scraper. 2. Apply a thin, even layer of Mechanic’s blueing dye (Dykem) onto the valve seat.
  • Page 88 POWR Power unit 2. Cut the surface of the valve seat with a 45° cutter by turning the cutter clockwise until the valve seat face has become smooth. 60˚ S69J5890 b Previous contact width 5. Use a 45° cutter to adjust the contact width of the valve seat to specification.

  • Page 89: Checking The Rocker Arms And Rocker Arm Shaft

    Cylinder head 7. If the valve seat contact area is too nar- CAUTION: row and situated near the top edge of the valve face, use a 30° cutter to cut the top Do not get the lapping compound on the edge of the valve seat.

  • Page 90: Checking The Camshaft

    POWR Power unit Checking the camshaft 1. Measure the cam lobe. Replace if out of specification. Camshaft journal diameter c: 36.925–36.945 mm (1.4537–1.4545 in) Camshaft journal diameter d: Cam lobe a: 36.935–36.955 mm Intake and exhaust: (1.4541–1.4549 in) 30.834–31.034 mm Cylinder head journal inside (1.2139–1.2218 in) diameter e:...

  • Page 91: Checking The Oil Pump

    Cylinder head S6D55560 S6D55570 Clearance a: 0.09–0.15 mm (0.0035–0.0059 in) Cylinder head warpage limit: Clearance b: 0.10 mm (0.0039 in) Within 0.12 mm (0.047 in) Clearance c: Checking the oil pump 0.03–0.08 mm (0.0012–0.0031 in) 1. Measure the oil pump rotor clearances as shown.

  • Page 92: Installing The Camshaft

    POWR Power unit 2. Install the valve 2, valve spring seat 3, 4. Lightly tap the valve spring retainer with valve spring 4, and valve spring retainer a plastic hammer to set the valve cotter 5 in the sequence shown, and then securely.

  • Page 93: Installing The Rocker Arm Shaft Assembly

    Cylinder head S6D55660 Rocker arm shaft bolt: 18 N·m (1.8 kgf·m, 13.3 ft·lb) Installing the oil pump Installing the rocker arm shaft 1. Install the oil pump 1 by aligning the oil pump drive shaft a with the camshaft pin assembly 1.

  • Page 94: Cylinder Block

    POWR Power unit Cylinder block Part name Q’ty Remarks Oil filter Union bolt Exhaust cover Holder M6 × 35 mm Bolt Thermostat cover Gasket Not reusable Thermostat Gasket Not reusable M8 × 35 mm Bolt Engine hanger Filter Steel Gasket Not reusable Plug Steel...
  • Page 95 Cylinder block Part name Q’ty Remarks Balancer piston Cover O-ring Not reusable M6 × 20 mm Bolt M8 × 82 mm Bolt M6 × 35 mm Bolt Crankcase Main bearing Bolt Connecting rod assembly Connecting rod bearing Oil seal Not reusable Balancer rod Crankshaft Oil seal...
  • Page 96 POWR Power unit Part name Q’ty Remarks Cylinder block Piston ring assembly Piston Piston pin Clip Not reusable 5-35 6D55F11...

  • Page 97: Disassembling The Cylinder Block

    Cylinder block Disassembling the cylinder block 1. Remove thermostat cover exhaust cover by removing the bolts in the sequence shown. S6D55730 5. Remove the crankcase bolts in the 2. Remove the oil filter. sequence shown. S6D55760 NOTE: Be sure to clean up any oil spills. 6.

  • Page 98: Checking The Balancer

    POWR Power unit 8. Remove the piston pin clips 4 and pis- Piston diameter a: ton pin, and then remove the piston. 64.950–64.965 mm (2.5571–2.5577 in) Measuring point b: 2.0 mm (0.08 in) up from the bottom of the piston skirt Oversize piston diameter: Oversize 1st: 65.200–65.215 mm...

  • Page 99: Checking The Piston Clearance

    Cylinder block 3. Check the piston ring end gap d at the Out-of-round limit: specified measuring point. Replace if out (measuring point a) –D of specification. (measuring point c) –D 0.05 mm (0.0020 in) Checking the piston clearance 1. Replace the piston and piston rings as a set or the cylinder block, or all parts if out of specification.

  • Page 100: Checking The Piston Ring Grooves

    POWR Power unit Checking the piston ring grooves Piston ring side clearance: 1. Measure piston ring grooves. Top ring a: Replace the piston if out of specification. 0.02–0.06 mm (0.0008–0.0024 in) 2nd ring b: 0.02–0.06 mm (0.0008–0.0024 in) Oil ring c: 0.04–0.18 mm (0.0016–0.0070 in) Checking the piston pin boss bore...

  • Page 101: Checking The Connecting Rod Small End Inside Diameter

    Cylinder block Checking the connecting rod small end inside diameter 1. Measure the connecting rod small end inside diameter a. Replace the connect- ing rod if out of specification. S6D55810 Connecting rod small end inside diameter a: 15.985–15.998 mm S6D55820 (0.6293–0.6298 in) Crankshaft journal diameter a: Checking the connecting rod big end...

  • Page 102: Checking The Crankpin Oil Clearance

    POWR Power unit Checking the crankpin oil clearance 1. Clean the bearings and the connecting rod. 2. Install the upper bearing into the con- necting rod 1 and the lower bearing into the connecting rod cap 2. NOTE: • Install the connecting rod bearings in their NOTE: original positions.

  • Page 103: Selecting The Connecting Rod Bearing

    Cylinder block 6. Remove the connecting rod cap and Connecting rod measure the width of the compressed Bearing color b mark a Plastigauge (PG-1) on each crankpin. Blue Replace the connecting rod bearing if out of specification. Black Brown Checking the crankshaft main journal oil clearance 1.

  • Page 104: Selecting The Crankshaft Main Bearing

    POWR Power unit 4. Put a piece of Plastigauge (PG-1) on each main journal parallel to the crank- shaft. Crankshaft main journal oil clearance: 0.012–0.044 mm NOTE: (0.0005–0.0017 in) Do not put the Plastigauge (PG-1) over the oil hole in the main journals of the crankshaft. Selecting the crankshaft main bearing 1.

  • Page 105: Assembling The Pistons And Cylinder Block

    Cylinder block Assembling the pistons and cylinder block 45˚ 45˚ 1. Assemble the piston 1, connecting rod 2, piston pin 3, and piston pin clips 4. #1,#4 S6D55900 CAUTION: Do not scratch the pistons or break the piston rings. NOTE: After installing the piston rings, check that they move smoothly.
  • Page 106 POWR Power unit 5. Install the piston with the “UP” mark on the piston crown facing towards the fly- wheel magnet. NOTE: Apply engine oil to the side of the pistons and NOTE: piston rings before installation. Apply engine oil to the inner oil seals before installation.
  • Page 107 Cylinder block 10. Install half of the main bearings into the 1–6 Crankcase bolt (M8): crankcase. 1st: 15 N·m (1.5 kgf·m, 11.1 ft·lb) NOTE: 2nd: 30 N·m (3.0 kgf·m, 22.1 ft·lb) • Install the main bearings in their original 7–B Crankcase bolt (M6): positions.

  • Page 108: Installing The Cylinder Head

    POWR Power unit 16. Before installing the oil filter, be sure to supply engine oil to the oil passage h. S6D55A10 Exhaust cover bolt: S6D55990 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 17. Install the oil filter, and then tighten it to 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb) the specified torque using the oil filter Thermostat cover bolt:...
  • Page 109 Cylinder block Cylinder head bolt (M9): 1st: 23 N·m (2.3 kgf·m, 17.0 ft·lb) 2nd: 46 N·m (4.6 kgf·m, 34.0 ft·lb) Cylinder head bolt (M6): 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb) 2. Install the cylinder head cover, and then tighten the bolts.

  • Page 110: Installing The Power Unit

    POWR Power unit 6. Connect the blowby hose 7. 7. Adjust the valve clearance. Valve clearance: Intake: 0.15–0.25 mm (0.006–0.010 in) Exhaust: 0.25–0.35 mm (0.010–0.014 in) NOTE: For adjustment procedures, see “Checking S6D55A50 the valve clearance”. 7. Connect the throttle cable 8 and shift cable 9 (remote control model), or throt- Installing the power unit tle cables 0 (tiller handle model), and...
  • Page 111 Cylinder block 10. Install the flywheel magnet. 12. Install all parts removed during disas- sembly. CAUTION: Apply force in the direction of the arrows shown to prevent the flywheel holder from slipping off easily. NOTE: Apply engine oil to the flywheel magnet nut before installation.
  • Page 112 POWR Power unit — MEMO — 5-51 6D55F11...

  • Page 113: Lowr

    LOWR Lower unit Special service tools ..................6-1 Lower unit ....................... 6-4 Removing the lower unit ................6-7 Removing the water pump................. 6-7 Checking the water pump................6-8 Propeller shaft housing ................. 6-9 Removing the propeller shaft housing assembly........6-11 Disassembling the propeller shaft assembly ...........6-11 Disassembling the propeller shaft housing..........

  • Page 114: Lower Unit

    LOWR Lower unit Special service tools Bearing housing puller claw S Bearing puller assembly 90890-06564 90890-06535 Stopper guide plate Needle bearing attachment 90890-06501 90890-06608, 90890-06611, 90890-06615 Center bolt Driver rod L3 90890-06504 90890-06652 Bearing separator Ball bearing attachment 90890-06534 90890-06635, 90890-06637 Stopper guide stand Driver rod LS 90890-06538...
  • Page 115 Special service tools Driver rod SS Bearing outer race attachment 90890-06604 90890-06625, 90890-06628 Bearing depth plate Driver rod LL 90890-06603 90890-06605 Bearing inner race attachment Pinion height gauge 90890-06640, 90890-06643, 90890-06644 90890-06710 Drive shaft holder 3 Pinion height gauge plate B 90890-06517 90890-06712 Driver rod SL...

  • Page 116: Lower Unit

    LOWR Lower unit Shimming plate 90890-06701 Backlash indicator 90890-06706 Magnet base plate 90890-07003 Dial gauge set 90890-01252 Magnet base B 90890-06844 6D55F11...
  • Page 117 Special service tools / Lower unit Lower unit Part name Q’ty Remarks Lower unit Check screw Gasket Not reusable Drain screw Adjusting nut Locknut Cooling water inlet cover M6 × 35 mm Bolt Washer Anode ø5 × 26 mm Screw M10 ×...
  • Page 118 LOWR Lower unit Part name Q’ty Remarks Collar Washer Cotter pin Not reusable Dowel 6D55F11...
  • Page 119 Lower unit Part name Q’ty Remarks Water tube L-transom model O-ring Not reusable L-transom model O-ring Not reusable S-transom model Water tube S-transom model O-ring Not reusable S-transom model M6 × 40 mm Bolt Extension plate Cover Water pump housing Insert cartridge O-ring Not reusable...

  • Page 120: Removing The Lower Unit

    LOWR Lower unit 4. Loosen the locknut 3, and then remove Removing the lower unit the adjusting nut 4. 1. Drain the gear oil. 5. Loosen the bolts 5, and then remove the lower unit from the upper case. 2. Shift the remote control lever or shift lever to neutral, place a block of wood between the anti-cavitation plate and propeller to keep the propeller from turn-...

  • Page 121: Checking The Water Pump

    Lower unit Checking the water pump 1. Check the water pump housing for defor- mation. Replace if necessary. 2. Check the impeller and insert cartridge for cracks or wear. Replace if necessary. 3. Check the Woodruff key 1 and the key- way a in the drive shaft for wear.

  • Page 122: Propeller Shaft Housing

    LOWR Lower unit Propeller shaft housing Part name Q’ty Remarks Shift plunger Dog clutch Cross pin Spring Spring Propeller shaft Washer Reverse gear Reverse gear shim — O-ring Not reusable Ball bearing Not reusable O-ring Not reusable Propeller shaft housing Needle bearing Oil seal Not reusable...
  • Page 123 Propeller shaft housing Part name Q’ty Remarks M6 × 25 mm Bolt Shift rod bracket Shift rod plate O-ring Not reusable Oil seal housing Dowel Gasket Not reusable Shift rod 6-10 6D55F11...

  • Page 124: Removing The Propeller Shaft Housing Assembly

    LOWR Lower unit Removing the propeller shaft housing assembly 1. Remove the bolts, and then pull out the propeller shaft housing assembly. Bearing separator 1: 90890-06534 Bearing housing puller claw S 1: Stopper guide plate 2: 90890-06501 90890-06564 Stopper guide stand 3: Stopper guide plate 2: 90890-06501 90890-06538 Center bolt 3: 90890-06504...

  • Page 125: Disassembling The Oil Seal Housing

    Propeller shaft housing 2. Check the propeller shaft for bends or wear. Replace if necessary. 3. Measure the propeller shaft runout. Needle bearing attachment 8: 90890-06615 Driver rod L3 9: 90890-06652 S6D56510 Disassembling the oil seal housing Runout limit: 0.02 mm (0.0008 in) 1.

  • Page 126: Assembling The Propeller Shaft Housing

    LOWR Lower unit Assembling the propeller shaft Needle bearing attachment 4: housing 90890-06611 1. Install the needle bearing into the propel- Driver rod L3 5: 90890-06652 ler shaft housing to the specified depth. Depth d: 13.0–13.5 mm (0.512–0.532 in) Depth e: 6.0–6.5 mm (0.236–0.256 in) 3.

  • Page 127: Assembling The Oil Seal Housing

    Propeller shaft housing Needle bearing attachment 0: 90890-06608 Assembling the oil seal housing 1. Apply grease to new oil seals, and then install them into the oil seal housing to the specified depth. Ball bearing attachment 1: 90890-06635 Driver rod LS 2: 90890-06606 Depth a: 5.5–6.0 mm (0.217–0.236 in) 6-14...
  • Page 128 LOWR Lower unit Drive shaft and lower case Part name Q’ty Remarks Drive shaft Taper roller bearing assembly Not reusable Pinion shim — Sleeve Needle bearing Pinion Forward gear shim — Taper roller bearing assembly Not reusable Forward gear Lower case 6-15 6D55F11...

  • Page 129: Drive Shaft And Lower Case

    Drive shaft and lower case Removing the drive shaft 1. Remove the drive shaft assembly and pinion, and then pull out the forward gear. CAUTION: Do not reuse the bearing, always replace it with a new one. S68S6150 Drive shaft holder 3 1: 90890-06517 Bearing separator 1: 90890-06534 Disassembling the drive shaft Disassembling the lower case...

  • Page 130: Checking The Pinion And Forward Gear

    LOWR Lower unit 2. Remove the drive shaft bearing outer Checking the drive shaft race, shim(s), and drive shaft sleeve. 1. Check the drive shaft for bends or wear. Replace if necessary. 2. Measure the drive shaft runout. NOTE: Install the claws as shown. S6D56520 Stopper guide plate 3: 90890-06501 Runout limit: 0.5 mm (0.020 in)

  • Page 131: Assembling The Forward Gear

    Drive shaft and lower case Depth c: CAUTION: 185–186 mm (7.283–7.323 in) Add or remove shim(s), if necessary, if replacing the forward gear or lower case. 2. Install the sleeve, original shim(s), and drive shaft bearing outer race. Bearing outer race attachment 6: 90890-06625 Driver rod LL 7: 90890-06605 Assembling the forward gear...

  • Page 132: Installing The Pinion

    LOWR Lower unit Installing the pinion 1. Install the forward gear, then the drive shaft assembly, pinion, and pinion nut, and then tighten the nut to the specified torque. S6D56260 Propeller shaft housing bolt: 11 N·m (1.1 kgf·m, 8.1 ft·lb) Installing the water pump and shift S68S6410 1.
  • Page 133 Drive shaft and lower case 5. Install the new O-ring 9 and insert car- tridge 0 into the pump housing A, and then apply grease to the inside of the insert cartridge. S6D56300 NOTE: • When installing the pump housing, apply grease to the inside of the housing, and then turn the drive shaft clockwise while pushing down the pump housing.

  • Page 134: Installing The Lower Unit

    LOWR Lower unit 5. Install the trim tab 5 to its original posi- Installing the lower unit tion, and then tighten the trim tab bolt 6. 1. Set the remote control lever or shift lever to reverse. È S6D56310 É Lower case mounting bolt 2: S6D56320 37 N·m (3.7 kgf·m, 27.3 ft·lb)
  • Page 135 Drive shaft and lower case 8. Install the check screw and quickly install the drain screw. WARNING • Do not hold the propeller with your hands when loosening or tightening it. • Be sure to remove the clip from the engine stop lanyard switch.

  • Page 136: Shimming

    LOWR Lower unit Shimming 42.5 24.0 24.0 S6D56370 6-23 6D55F11...

  • Page 137: Selecting The Pinion Shims

    Shimming Shimming 2. Install the pinion and pinion nut, and then tighten the nut to the specified torque. NOTE: • Shimming is not required when assembling Pinion nut: the original lower case and inner parts. 50 N·m (5.0 kgf·m, 36.9 ft·lb) •...

  • Page 138: Selecting The Forward Gear Shims

    LOWR Lower unit 4. Calculate the pinion shim thickness (T3) Example: as shown in the examples below. If “T3” is 1.25 mm, then the pinion shim is 1.3 If “T3” is 1.75 mm, then the pinion shims are 0.7 and 1.1 mm. Selecting the forward gear shims 1.

  • Page 139: Selecting The Reverse Gear Shims

    Shimming Selecting the reverse gear shims 1. Install the ball bearing onto the propeller shaft housing. 2. Measure the bearing housing height (M2) as shown. S6D56400 NOTE: “F” is the deviation of the lower case dimen- sion from standard. The “F” mark a is stamped on the anode mounting surface of the lower case in 0.01 mm units.

  • Page 140: Backlash

    LOWR Lower unit 3. Calculate the reverse gear shim thick- Example: ness (T2) as shown in the examples If “T2” is 1.05 mm, then the reverse gear below. shim is 1.0 mm. If “T2” is 1.20 mm, then the reverse gear shim is 1.1 mm.
  • Page 141 Shimming / Backlash 7. Remove the special service tools from the propeller shaft. 8. Apply a load to the reverse gear by installing the propeller 8 (without the spacer 9), the collar 0, then the washer A as shown. NOTE: Install the dial gauge so that the plunger a contacts the mark b on the backlash indica- NOTE:...
  • Page 142 LOWR Lower unit 10. Add or remove shim(s) if out of specifica- tion. Reverse gear Shim thickness backlash Less than To be decreased by (1.29 – M) × 0.49 0.92 mm (0.0362 in) More than To be increased by (M – 1.29) × 0.49 1.65 mm (0.0650 in) M: Measurement Available shim thicknesses:...

  • Page 143: Brkt

    BRKT Bracket unit Tiller handle ....................7-1 Assembling the tiller handle............... 7-3 Bottom cowling ....................7-4 Upper case, steering arm ................7-6 Draining the engine oil................7-10 Disassembling the oil pan................7-10 Checking the oil strainer ................7-10 Checking the oil pan ................7-10 Assembling the oil pan ................7-10 Removing the steering arm ..............
  • Page 144 BRKT Bracket unit Tiller handle Part name Q’ty Remarks Throttle cable Engine stop lanyard switch Grommet Shift link rod Shift lever Washer Wave washer Collar M6 × 30 mm Bolt Self-locking nut Cable guide Bushing Steering bracket Plastic washer 6D55F11...
  • Page 145 Tiller handle Part name Q’ty Remarks Metal washer Wave washer Bushing Tiller handle bracket Throttle friction adjuster Throttle grip ø5 × 25 mm Screw Washer Spring Bushing Throttle shaft Friction piece M6 × 20 mm Bolt Plate Engine stop lanyard 6D55F11...

  • Page 146: Bracket Unit

    BRKT Bracket unit Assembling the tiller handle NOTE: 1. Install the engine stop lanyard switch 1 • Route the engine stop lanyard switch lead to the tiller handle bracket 2. Tighten the 9 and throttle cables 0 and A as shown. nut to the specified torque.

  • Page 147: Bottom Cowling

    Tiller handle / Bottom cowling Bottom cowling Part name Q’ty Remarks Shift rod lever joint Remote control model M6 × 25 mm Bolt Bracket Start-in-gear protection lever Shift rod lever Shift rod Bottom cowling Rubber seal Grommet Grommet Remote control model Grommet Remote control model Grommet...
  • Page 148 BRKT Bracket unit Part name Q’ty Remarks Grommet Collar Water outlet Bolt Hook M6 × 20 mm Bolt Lever Bushing Bushing Wave washer Washer Cowling lock lever Grommet Tiller handle model Grommet Remote control model Cable guide Remote control model M6 ×...

  • Page 149: Upper Case, Steering Arm

    Bottom cowling / Upper case, steering arm Upper case, steering arm Part name Q’ty Remarks Mount housing Rubber damper Rubber damper M10 × 80 mm Bolt M10 × 120 mm Bolt ø6 × 8 mm Screw Ground lead Grease nipple M8 ×...
  • Page 150 BRKT Bracket unit Part name Q’ty Remarks Bushing Straight key Bushing O-ring Not reusable Bushing Remote control model Washer Remote control model Steering hook Remote control model M8 × 20 mm Bolt Rubber seal 6D55F11...
  • Page 151 Upper case, steering arm Part name Q’ty Remarks Upper case ø5 × 15 mm Screw Baffle plate Dowel M8 × 30 mm Bolt Gasket M6 × 50 mm Bolt Washer Bracket Exhaust manifold Gasket Not reusable Oil pan Gasket Not reusable M14 ×...
  • Page 152 BRKT Bracket unit Part name Q’ty Remarks Gasket Not reusable Exhaust guide Oil seal Not reusable Grommet Anode Cover M5 × 12 mm Bolt Cover M6 × 20 mm Bolt Cooling water pipe Rubber seal M6 × 16 mm Bolt Oil strainer M6 ×...

  • Page 153: Draining The Engine Oil

    Upper case, steering arm Draining the engine oil 2. Check the cooling water pipe for defor- mation or corrosion. Replace if neces- 1. Place a drain pan under the drain hole, sary. and then remove the drain bolt and let the oil drain completely.

  • Page 154: Removing The Steering Arm

    BRKT Bracket unit 4. Install the cooling water pipe 4. 5. Install the oil pan 5 and bolts, and then tighten the bolts finger tight. 6. Install the exhaust manifold 6, seal, and bolts, and then tighten the bolts finger tight.

  • Page 155: Installing The Steering Arm

    Upper case, steering arm 4. Tighten the lower mounting nuts 5 to the Installing the steering arm specified torque, then tighten the lower 1. Install the washer 1, bushing 2, and mounting nuts 7 to the specified torque. straight key 3 onto the steering arm 4. 2.

  • Page 156: Clamp Brackets, Swivel Bracket

    BRKT Bracket unit Clamp brackets, swivel bracket Part name Q’ty Remarks Tilt pin Spring M8 × 255 mm Bolt Collar Washer Cap nut Self-locking nut Plate Through tube Clamp bracket Washer Bushing Swivel bracket Clamp bracket Washer 7-13 6D55F11...
  • Page 157 Clamp brackets, swivel bracket Part name Q’ty Remarks Plastic washer Tilt stopper plate Wave washer Bolt Bushing Circlip Collar Bushing Grease nipple 7-14 6D55F11...
  • Page 158 BRKT Bracket unit Part name Q’ty Remarks Spring Tilt lock rod Tilt lever ø5 × 5 mm Screw Collar Circlip Tilt lock lever Bushing Bushing Tilt support bar Spring Pin 1 Pin 2 Tilt lock plate Tilt lock arm Collar 7-15 6D55F11...

  • Page 159: Removing The Clamp Brackets

    Clamp brackets, swivel bracket 3. Install the tilt support bar A and pin B, Removing the clamp brackets and then insert the tilt lock lever C par- 1. Remove the tilt pin, and then remove the tially into the swivel bracket. clamp bracket bolt, clamp bracket nut, and collar.

  • Page 160: Installing The Clamp Brackets

    BRKT Bracket unit 5. Install the screw G to the tilt lever E, Tilt stopper plate nut: and then install the circlip H to the pin 24 N·m (2.4 kgf·m, 17.7 ft·lb) Self-locking nut 1: 45 N·m (4.5 kgf·m, 33.2 ft·lb) Clamp bracket nut 4: 8 N·m (0.8 kgf·m, 5.9 ft·lb) 6.

  • Page 161: Elec

    – ELEC Electrical systems Special service tools ..................8-1 Checking the electrical components............8-2 Measuring the peak voltage ..............8-2 Measuring the lower resistance..............8-2 Electrical components................... 8-3 Front and aft views ..................8-3 Port and starboard views................8-4 Wiring diagram ..................8-5 Checking the ignition spark gap ..............8-7 Checking the spark plug caps ..............8-7 Checking the ignition coil................8-7...

  • Page 162: Electrical Systems

    – ELEC Electrical systems Special service tools Ignition tester 90890-06754 Digital circuit tester 90890-03174 Peak voltage adapter B 90890-03172 Test harness (2 pins) New: 90890-06868 Current: 90890-06768 Vacuum/pressure pump gauge set 90890-06756 6D55F11...

  • Page 163: Checking The Electrical Components

    Special service tools / Checking the electrical components Checking the electrical Measuring the lower resistance When measuring a resistance of 10 Ω or less components with the digital circuit tester, the correct mea- Measuring the peak voltage surement cannot be obtained due to the internal resistance of the tester.

  • Page 164: Electrical Components

    – ELEC Electrical systems Electrical components Front and aft views 1 CDI unit 2 Ignition coil 3 Engine stop lanyard switch coupler (remote control model) 6D55F11...

  • Page 165: Port And Starboard Views

    Electrical components Port and starboard views 1 Oil pressure switch 2 Thermo sensor 3 Pulser coil 4 Spark plugs 5 Prime Start 6D55F11...

  • Page 166: Wiring Diagram

    – ELEC Electrical systems Wiring diagram 1 CDI unit Color code 2 Oil pressure switch : Black 3 Stator coil : Orange 4 Pulser coil : Pink 5 Thermo sensor : Red 6 Ignition coil : White 7 Wiring harness : Yellow 8 Prime Start B/W : Black/white...
  • Page 167 Electrical components S6D5WD01 6D55F11...

  • Page 168: Checking The Ignition Spark Gap

    – ELEC Electrical systems Checking the ignition spark gap 1. Disconnect the spark plug caps from the spark plugs. 2. Connect a spark plug cap to the special service tool. 2. Measure the spark plug cap resistance. Replace if out of specification. S6D58040 Ignition tester: 90890-06754 3.

  • Page 169: Checking The Cdi Unit

    Electrical components Ignition coil resistance: Primary coil: Orange (O) – Black (B) 0.08–0.11 Ω at 20 °C (68 °F) Secondary coil: Spark plug wire – spark plug wire 3.4–4.7 kΩ at 20 °C (68 °F) S6D58090 Checking the CDI unit 1.

  • Page 170: Checking The Charge Coil

    – ELEC Electrical systems Checking the charge coil Digital circuit tester: 90890-03174 1. Measure the charge coil output peak volt- Peak voltage adapter B: age. Replace the stator coil if below 90890-03172 specification. Power bobbin output peak voltage: Yellow/black (Y/B) – Yellow/black (Y/B) Unloaded r/min...

  • Page 171: Checking The Engine Stop Lanyard Switch

    Electrical components 2. Measure the thermo sensor resistance. Lighting coil resistance Replace if out of specification. (reference data): Yellow (Y) – Yellow (Y) Thermo sensor resistance: 0.90–1.10 Ω at 20 °C (68 °F) Brown/black (Br/B) – Brown/black (Br/B) at 20 °C (68 °F): 1.13–1.38 kΩ Checking the engine stop lanyard at 50 °C (122 °F): 324–396 Ω...

  • Page 172: Checking The Oil Pressure Warning Indicator

    – ELEC Electrical systems Checking the oil pressure warning indicator 1. Connect a penlight battery (1.5 V) to the oil pressure warning indicator (LED). Replace if it does not light. CAUTION: Only use a penlight battery (1.5 V) when checking the LED. Other batteries (e.g., alkaline batteries or high-voltage batter- ies) will damage the diode.

  • Page 173: Trbl Shtg

    TRBL SHTG Troubleshooting Power unit....................... 9-1 6D55F11...
  • Page 174 TRBL SHTG Troubleshooting NOTE: • Before troubleshooting the outboard motor, check the compression pressure, valve clearance, the mounting and rigging of the outboard motor, and the operation of the manual starter. Also, make sure that specified fuel has been used. •...
  • Page 175 Power unit Good spark? Check the fuel system. Check the ignition coil resis- tance. Good condition? Replace the ignition coil. Check the spark plug cap resis- tance and the spark plug caps for salt buildup. Repair or replace the spark plug Good condition? caps.
  • Page 176 TRBL SHTG Troubleshooting Good condition? Check the fuel system. Replace the CDI unit. Fuel system Check the fuel filter for clogs and the hoses for leaks. Repair or replace the defective Clogs or leaks? parts. Check the fuel pump dia- phragms.
  • Page 177 Power unit Symptom 2: Engine speed at wide open throttle is low, engine speed decreases, or engine stalls (poor acceleration or poor deceleration). Symptom 3: Engine speed not stable at low speeds. • Air vent screw on the fuel tank is open. •...
  • Page 178 TRBL SHTG Troubleshooting Within specification? Adjust the pilot screw. Disassemble the carburetor and check the internal parts for clogs, debris, or wear. Clogs, debris, Clean or replace the defective or wear? parts. Check the ignition system or lubrication system. 6D55F11...
  • Page 179 Power unit Lubrication system Check the engine oil level. Add engine oil to the correct At specified level? level. Check the oil pressure. Check the oil pump for debris or Within specification? oil leaks. Check the oil Debris or leaks? passage.
  • Page 180 Index Checking the crankshaft main journal oil clearance ..........5-42 Adjusting the throttle cable Checking the cylinder bore ....... 5-37 (remote control model)......3-8 Checking the cylinder head ...... 5-29 Adjusting the throttle cables Checking the diaphragms and valves..4-6 (tiller handle model) ........3-8 Checking the drive shaft ......
  • Page 181 Index Checking the propeller shaft housing..6-12 Checking the pulser coil......8-8 Fire prevention..........1-3 Checking the remote control cables Front and aft views ........8-3 (remote control model)......1-7 Fuel hoses and fuel filter ......4-3 Checking the rocker arms and Fuel pump........... 4-4 rocker arm shaft ........5-28 Fuel system ..........
  • Page 182 Index Parts, lubricants, and sealants....1-3 Wiring diagram ........... 8-5 Port and starboard views ......8-4 Power unit ......2-3 Predelivery checks........1-6 Propeller selection ........1-5 Propeller shaft housing .......6-9 Propeller size ..........1-5 Refacing the valve seat......5-26 Removing the carburetor ......4-11 Removing the clamp brackets....7-16 Removing the cylinder head .....5-23 Removing the drive shaft ......6-16 Removing the lower unit ......6-7...
  • Page 184 YAMAHA MOTOR CO., LTD. Printed in Japan Nov. 2003 – 0.4 × 1 CR Printed on recycled paper...

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