TOHATSU MFS 2 Service Manual
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TOHATSU MFS 2 Service Manual

TOHATSU MFS 2 Service Manual

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B No.003-21058-0
07-04 NB-2600

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  • Page 1 B No.003-21058-0 07-04 NB-2600...
  • Page 2 Introduction Before reading this manual This service manual provides information that is needed for inspection, service and repair of applicable outboard motors. For information about operation of the products that are not described in this document, refer to the owners manual. For our customers' safe and comfortable use of the products for long term, it is essential to maintain the performance and quality of the outboard.

  • Page 3: Service Information

    Description of Pictogram The following symbols represent the contents of individual chapters. Service Fuel System Service Data Maintenance Information (Carburetor) Electrical Power Unit Lower Unit Bracket System Wiring r/min Troubleshooting Accessories Diagrams The following symbols indicate items needed for the service. Lubrication Tightening Special Tool...

  • Page 4: Table Of Contents

    1.Service Information 10) Inspection of Gear Case (for leakage) …… 3-11 11) Inspection of Spark Plug …………………… 3-12 Identification (Engine Serial Number) 1-2 12) Inspection of Compression Pressure …… 3-13 Securing of work safety ………………… 1-2 13) Inspection and Adjustment of Valve Clearances … 3-14 1) Fire Prevention ………………………………...
  • Page 5 15) Inspection of Lifter ………………………… 5-20 21) Disassembly of Drive Shaft ……………… 6-14 16) Inspection of Cam Shaft …………………… 5-21 22) Inspection of Drive Shaft…………………… 6-14 17) Inspection of Piston Outer Diameter ……… 5-22 23) Inspection of Forward Gear and Pinion Gear 18) Inspection of Cylinder Inner Diameter ……...
  • Page 6 INDEX Service Information Service Data Maintenance Fuel System (Carburetor) Power Unit Lower Unit Bracket Electrical System Troubleshooting 4st 2/2.5/3.5 2007...
  • Page 7 Service Information 1 Identification (Engine Serial Number) 2) Gear Shift ………………………………… 1-7 …… 1-2 2 Securing of work safety 3) Engine Oil ………………………………… 1-7 …………… 1-2 4) Gear Oil …………………………………… 1-7 1) Fire Prevention …………………………… 1-2 5) Fuel Tank and Fuel Line ………………… 1-8 2) Ventilation …………………………………...

  • Page 8: Identification (Engine Serial Number)

    Service Information 1. Identification (Engine Serial Number) Engine serial number is stamped on the swivel bracket of outboard motor body. 1 Model Name 2 Model Type Tokyo, Made in Japan 2006 Model F3.5A 3 Serial Number SERIAL No. XXXXXXXX RATED POWER FULL THROTTLE RANGE 5000 6000...

  • Page 9: Tools

    5) Tools Use specified special tools to prevent damage to parts and to perform work safely and correctly. Be sure to follow installation procedures described in this manual and use tightening torque specified. 3AC728710 6) Recommendations on Service Remove foreign substances and dirt from outboard motor and individual parts by cleaning.

  • Page 10: Cautions In Disassembling And Assembling Components

    Service Information 7) Cautions in Disassembling and Assembling Components Secure outboard motor to dedicated stand firmly. Take special care not to scratch painted surface or mating surfaces of cylinder and crankcase. Replace unreusable parts such as packings, gaskets, O rings, oil seals, spring pins or split pins with new ones after they were removed.

  • Page 11: Tools And Instruments

    3. Tools and Instruments 1) Test Propeller P/N. 3AB-64111-0 Outer diameter : 120mm Width : 16mm (Reference value) Speed at WOT Model (Wide Open Throttle) (r/min) 4,500 - 5,500 F2A/F2.5 A 5,000 - 6,000 F3.5 A This test propeller has been designed for break- in operation and load test operation.

  • Page 12: List Of Special Tool

    Service Information 3) List of Special Tool Spring Pin Tool A Spring Pin Tool B Thickness Gauge Center Plate 3 P/N. 345-72227-0 P/N. 345-72228-0 P/N. 353-72251-0 P/N. 3AB-99701-0 Used in combination with driver rod and Installing spring pin Measuring gaps Removing spring pin bearing attachment to locate lower gear case bearing...

  • Page 13: Predelivery Inspection

    4. Predelivery Inspection å ∫ Lighter 1) Steering Handle å Check installations for tension and play. Heavier ∫ Adjust steering friction. ç ∂ ç Check throttle grip for movement. (Fully Open a / Fully Closed b) ∂ Adjust throttle friction. 1 Steering Adjust Screw c Lighter d Heavier 2) Gear Shift...

  • Page 14: Fuel Tank And Fuel Line

    Service Information 5) Fuel Tank and Fuel Line Check that fuel tank contains sufficient amount of gasoline, fuel line is connected and is free of leaks. CAUTION Since this is a 4 stroke engine model, do not use fuel mixed with engine oil. Use of fuel mixed with engine oil will cause engine trouble.

  • Page 15: Inspection Of Stop Switch

    8) Inspection of Stop Switch Press stop switch 1 hard or pull out lock 2 from stop switch 1 to check that engine stops. 9) Cooling Water Check Port Check that cooling water check port 1 discharges water during engine runs. 10) Idle Operation After engine has warmed up in neutral, use tachometer to check idle engine speed is as specified.

  • Page 16: Propeller Selection

    Service Information 11) Propeller Selection Select a propeller that is best-suited to type of boat and application. Range of operating engine revolution at WOT F2/2.5 : 4,500 - 5,500r/min F3.5 : 5,000 - 6,000r/min CAUTION Incorrect-selection of propeller can cause adverse effects engine...

  • Page 17: Break-In Operation

    5. Break-in Operation Break-in operation is needed to smooth sliding surfaces between components such as pistons and cylinder, piston rings, piston pins, crank shaft, connecting rods, and intake and exhaust valves. Break-in Operation…10 hours Time 10 minutes 2 hours 3 hours 10 hours 3/4 of WOT or less at 1/2 of WOT or less at...

  • Page 18: Checks After Test Run

    Service Information 7. Checks After Test Run Check that power unit, lower unit and bracket are free of looseness or play. Check that no water is present in gear oil. Check that no fuel leakage exists in the cowl. Check that no oil and water leak in the cowl and no water is present in engine oil.

  • Page 19: Service Data

    Service Data Outline Dimensons ……………………… 2-2 Specifications ……………………………… 2-6 1） Engine Dimensions ……………………… 2-2 Maintenance Data………………………… 2-8 2） Clamp Dimensions ……………………… 2-3 Tightening Torque Data ………………… 2-12 Cooling Water System Diagram……… 2-4 Sealant Application Locations ……… 2-14 Wiring Diagram …………………………… 2-5...

  • Page 20: Outline Dimensons

    Service Data 1.Outline Dimensons 1）Engine Dimensions Item Type Unit mm/in 14.84 mm/in 25.55 mm/in 30.55 mm/in 17.13 mm/in 22.13 mm/in 17.56 mm/in 4.25 mm/in 13.94 mm/in 13.23 mm/in 11.93 mm/in 2.28 mm/in 8.19 mm/in 24.72 mm/in 14.29 mm/in 13.39 mm/in 10.87 mm/in 17.83...

  • Page 21: 2）Clamp Dimensions

    2）Clamp Dimensions CENTER LINE 70.5mm (2.77in) 63.5mm 63.5mm (2.50in) (2.50in) TOP OF BOAT TRANSOM 45.5mm 45.5mm (1.79in) Allowable Transom Thickness 30-58mm(1.18-2.28 in) 4st 2/2.5/3.5 2007...

  • Page 22: Cooling Water System Diagram

    Service Data 2.Cooling Water System Diagram Thermostat1 Cylinder (with cylinder head)2 Water Discharging Water Feed Passage in Drive Passage in Shaft Housing Drive Shaft Housing Water Pipe9 Cooling Water Check Port5 Drive Shaft Water Pump0 Housing8 Exhaust Gas and Cooling Water Discharged Waterq Intakew 1Thermostat...

  • Page 23: Wiring Diagram

    3.Wiring Diagram 1Flywheel B: Black 2Igniter Br: Brown 3Stop Switch 4Ground 5Spark Plug 6Stop Switch Lanyard 4st 2/2.5/3.5 2007...

  • Page 24: Specifications

    Service Data 4.Specifications Outboard Model Item Unit F2.5A F3.5A Dimensions (approximate) Overall Length mm (in) 690 (27.2) Overall Width mm (in) 363 (14.3) mm (in) 1,026 (40.4) Overall Height mm (in) 1,153 (45.4) mm (in) 435 (17.1) Transom Length mm (in) 562 (22.1) Weight (approximate) kg (lbs)
  • Page 25 Outboard Model Item Unit F2.5A F3.5A Fuel & Oil Unleaded Gasoline (Research Octan Number 90 Type of Fuel or over, Pump posted Octane Number 87 or over) Fuel Tank Capacity L (US gal.) 1.0 (0.26) [Integral Fuel Tank] Starting Fuel Enrichment System Choke Valve System Fuel Pumping (Feed) System None (Gravitational System)

  • Page 26: Maintenance Data

    Service Data 5.Maintenance Data Item Standard Values Description Build up of carbon in combustion chamber Deposits in water jacket Wear of bore : Use cylinder gauge to measure inner diameter. 55.00mm (2.1654in) Cylinder Block/ Cylinder Head Seizure, cylinder liner damage, or wear Taper Out-of-roundness Outer Diameter...
  • Page 27 Functional Limit Action To Be Taken Clean to remove. Clean to remove. 55.06mm (2.1677in) Replace if over specified limit. Replace if severely damaged on the piston sliding surface, which cannot be repaired 0.06mm (0.0024in) with sand paper of No. 400 to 600, or if damaged over specified limit. 0.06mm (0.0024in) 54.90mm (2.1614in) Replace if under specified limit.
  • Page 28 Service Data Item Standard Values Description F2.5A F3.5A Setting Mark φ7.5 φ9 φ13 Venturi Diameter φ16 φ16 φ19 Throttle Bore Diameter Carburetor Main Jet (MJ) ＃58 ＃62 ＃68 φ1.4 φ1.4 φ1.8 Main Nozzle Inner Diam. (MN) Slow Jet (SJ) ＃38 ＃38 ＃38 Throttle Opening (at WOT)
  • Page 29 Functional Limit Action To Be Taken Adjust or replace. 5mm (0.2in) Replace if under specified limit. Adjust into specified range. Replace if out of specified range. * A digital tester may display values of reversed polarity and/or measurement values ranging from 2 - 6MΩ. Replace if out of specified range.

  • Page 30: Tightening Torque Data

    Service Data 6.Tightening Torque Data Tightening Torque Screw B Wrench Type of Fastened Components Fastener Pitch N・m lb・ft kgf・m Crankcase First Tightening Torque M6 x 1.0 Bolt Second Tightening Torque Oil Pan First Tightening Torque M6 x 1.0 Bolt Second Tightening Torque Connecting Rod First Tightening Torque M6 x 1.0...
  • Page 31 Value enclosed by ( ) is hex hole size. Screw B Tightening Torque Wrench Type of Fastened Components Fastener Pitch N・m lb・ft kgf・m 1342 Bracket Bolt M8 x 1.25 Nylon Nut 1342 1342 Swivel Bracket Bolt 1342 M6 x 1.0 Bolt Swivel 1342...

  • Page 32: Sealant Application Locations

    Service Data 7.Sealant Application Locations Applied to Remarks Shin Three Three Loctite Konishi Chuo Yuka Loctite etsu Bond Bond Silicones Centax 1342 1107 G１７ Camshaft Area of bearings, cams and gears ● Lifter ● Cam sliding face, push rod insertion area Push Rod Both ends ●...
  • Page 33 Applied to Remarks Shin Three Three Loctite Konishi Chuo Yuka Loctite etsu Bond Bond Silicones Centax 1342 1107 G１７ Shift Lever Body ● Betweenthe body and O-Ring O-Rings (2 pcs.) ● Whole area of the part Shift Lever Spring ● Whole area of the part Ceramic Ball Whole area of the part...
  • Page 34 Service Data Applied to Remarks Shin Three Three Loctite Loctite Konishi Chuo Yuka etsu Bond Bond Silicones Centax 1342 1107 G１７ LM-902 Steering Bracket ● Threaded area Inner and outer faces Bushing (Tiller Handle) ● Throttle Shaft ● Groove area, sliding area Tiller Spring (Friction) Whole area of the part...

  • Page 35: Maintenance

    Maintenance Special Tool ………………………………… 3-2 12) Inspection of Compression Pressure … 3-13 Inspection Schedule …………………… 3-3 13) Inspection and Adjustment of Valve Clearances … 3-14 Inspection Items ………………………… 3-4 14) Adjustment of Throttle Cable …………… 3-16 1) Inspection of Top Cowl ………………… 3-4 15) Inspection of Gear Shift Operation ……...

  • Page 36: Special Tool

    Maintenance 1. Special Tool Tachometer Compression Gauge P/N. 3AC-99030-0 P/N. 3AC-99010-0 Measuring engine revolution Measuring compression speed pressure 4st 2/2.5/3.5 2007...

  • Page 37: Inspection Schedule

    2. Inspection Schedule Inspection Period Initial 20 hours 50 hours 100 hours 200 hours Inspection Part Inspection Item Remarks or initial or Every or Every or Every 1 month 3 months 6 months year Carburetor Disassembly, cleaning and adjustment Fuel Filter Checking, Cleaning or replacement (Fuel Cock)

  • Page 38: Inspection Items

    Maintenance 3. Inspection Items 1) Inspection of Top Cowl Push top cowl to check for looseness and state of closing. 2) Inspection of Fuel System Check piping Remove top cowl and check each section for fuel leak, dirt, deterioration and damages. Clean or replace parts if necessary.

  • Page 39: Inspection Of Fuel Cock (Fuel Filter)

    4) Inspection of Fuel Cock (Fuel Filter) Check fuel cock 1 (fuel filter a ) for dirt and clogging, and Carburetor clean if necessary. Tank 5) Inspection of Fuel Cock Check that fuel cock 1 can be opened and closed normally. 4st 2/2.5/3.5 2007...

  • Page 40: Replacement Of Engine Oil

    Maintenance 6) Replacement of Engine Oil Oil Level Upper Limit (Center) 300cm 250cm Lower Limit Oil Specification Engine Oil : 4 Stroke Engine Oil API : SF, SG, SH 10W – 40 SAE : 10W-30, 10W-40 NMMA : FC-W Certified 10W-30 10W –...
  • Page 41 6. Pour new engine oil into oil inlet 3 until oil level reaches upper limit mark (center) of oil level gauge 4. Upper Limit (Center) 300cm 250cm Lower Limit 4st OIL Quantity of Engine Oil : 300cm （10 fl.oz） 7. Attach oil filler cap 1, start engine and idle for 5 minutes to warm up.

  • Page 42: Inspection Of Gear Oil Quantity

    Maintenance 7) Inspection of Gear Oil Quantity Tilt down outboard motor down to the vertical position. GEAR GEAR GEAR Remove upper oil plug 1 and check level of gear oil in the gear case. Over flow of some oil from plug hole as plug is removed indicates that gear case is filled with specified quantity of gear oil.
  • Page 43 Remove lower unit installation bolts 3 and nut 4, and pull lower unit ass'y downward to remove. Check drive shaft spline a for adhesion of oil, rust and wear. Remove bolt, and then, pump case (upper) 1 while pushing drive shaft downward b. •...

  • Page 44: Replacement Of Gear Oil

    Maintenance 9) Replacement of Gear Oil Set outboard motor vertical. Place drain oil pan below oil plug 1, remove lower oil plug 1 and then upper oil plug 2 to drain oil. Remove lower oil plug 1 first when draining. Check gear oil for presence of metal particles, change of color (abnormal if clouded), and viscosity.

  • Page 45: Inspection Of Gear Case (For Leakage)

    10) Inspection of Gear Case (for leakage) Drain gear oil. Refer to "9) Replacement of Gear Oil" in Chapter 3. Remove upper oil plug 1 and connect a commercially available leakage tester to this hole. 2Gasket Do not reuse. Apply specified pressure to gear base, and check if the pressure is maintained without further compression for 10 seconds.

  • Page 46: Inspection Of Spark Plug

    Maintenance 11) Inspection of Spark Plug Remove plug cap and then spark plug. Use spark plug cleaner or wire brush to clean spark plug electrode 1. Replace if necessary. Check electrode 1 for corrosion or excessive build up of carbon, and washer 2 for damage. Replace if necessary. Check spark plug gap a.

  • Page 47: Inspection Of Compression Pressure

    12) Inspection of Compression Pressure Start and idle engine for 5 minutes to warm up, and then stop. Shift gear into neutral (N). Remove lock plate (of stop switch lanyard) from stop switch. CAUTION To prevent accidental start of the engine, remove lock plate (of stop switch lanyard) from stop switch before measuring compression pressure.

  • Page 48: Inspection And Adjustment Of Valve Clearances

    Maintenance 13) Inspection and Adjustment of Valve Clearances Disconnect plug cap 1 connection, and then, remove spark plug and cylinder head cover 2. When removing or installing cylinder head cover without removing power unit, use 10 mm box wrench with large offset angle. Pull recoil starter 3 to turn flywheel clockwise until flywheel "T"...
  • Page 49 Loosen pivot lock nut 5 and then turn the pivot 6 so that valve clearance reaches specified value. • Turning pivot 6 clockwise makes valve clearance smaller. • Turning pivot 6 counterclockwise makes valve clearance larger. Tighten pivot lock nut 5 to specified torque, and check valve clearance again.

  • Page 50: Adjustment Of Throttle Cable

    Maintenance 14) Adjustment of Throttle Cable Turn throttle grip 1 to full close position a. Pull choke rod 2 fully d. Attach throttle cable 3 to throttle drum 4 taking care of the positions of low speed side cable e and high speed cable side f. Pull outer cable g of throttle cable 3 to the side shown with the arrow by hand, and lock it with the nut while applying tension to the cable.

  • Page 51: Inspection Of Gear Shift Operation

    15) Inspection of Gear Shift Operation Shift the lever 1 from neutral (N) to while rotating propeller, and then back to neutral (N) to check that shift operation is performed smoothly. Adjust positions of shift rod 2 and joint 3 if necessary. Shift lever 1 into neutral (N).

  • Page 52: Flushing With Water

    Maintenance 16) Flushing with Water CAUTION Touching rotating propeller could lead to injury. Be sure to remove propeller before running engine on the land. WARNING Exhaust gas contains carbon monoxide, which will cause gas poisoning. Do not start engine with outboard motor placed in a closed area such as boat house.

  • Page 53: Inspection Of Ignition Timing

    18) Inspection of Ignition Timing Adjusting system : Automatic control, requiring no manual adjustment. Run engine and use timing light to check ignition timing. 7 timings marks are found on the top of flywheel (TDC0ﾟ ("T"), BTDC5ﾟ, 10ﾟ, 15ﾟ, 20ﾟ, 25ﾟ, 30ﾟ). Read ignition timing with mark on the center of flywheel cover window.

  • Page 54: Inspection Of Thermostat

    Maintenance 22) Inspection of Thermostat Remove bolts, and then thermostat cap 1 and thermostat 2. Hang thermostat 2 in the water contained in vessel. Put thermometer in the water, and warm up water to measure valve opening temperature. Put a piece of thread in the closed valve gap and hang it in the water.

  • Page 55: Inspection Of Cooling Water Passages

    23) Inspection of Cooling Water Passages Check water strainer 1 for clogging. Clean if necessary. Set outboard motor in the water and start engine. Check that cooling water is discharged from cooling water check port 2. If not, check water pump and cooling water passage in the engine.

  • Page 56: Greasing Points

    Maintenance 24) Greasing Points Apply grease to throttle cable and sliding areas. aDo not lubricate here. Apply grease to pin of tilt stopper 2 and thrust supporter 3. Apply grease to propeller shaft. 3-22 4st 2/2.5/3.5 2007...

  • Page 57: Fuel System (Carburetor)

    Fuel System (Carburetor) Special Tool ………………………………… 4-2 4) Inspection of Fuel Cock ………………… 4-7 Parts Layout………………………………… 4-3 5) Inspection of Fuel Filter ………………… 4-7 Fuel Tank ……………………………………… 4-3 6) Inspection of Carburetor ………………… 4-8 Carburetor ……………………………………… 4-4 7) Assembling of Carburetor ……………… 4-9 Inspection Items …………………………...

  • Page 58: Special Tool

    Fuel System (Carburetor) 1.Special Tool Tachometer P/N. 3AC-99010-0 Measuring engine revolution speed 4st 2/2.5/3.5 2007...

  • Page 59: Parts Layout

    2. Parts Layout P/L Fig. 14 Fuel Tank 6 N·m (4 lb·ft) [0.6 kgf·m] 15-1 1342 1342 1342 15-2 Carburetor 1342 1342 1342 Ref. Description Remarks Q'ty Fuel Tank Fuel Tank Cover Collar, 6.2-9-10.7 Washer, 6-16-1.5 Bolt 3 M6 L=25mm Fuel Cock Fuel Cock Rod Seal Ring...

  • Page 60: Carburetor

    Fuel System (Carburetor) Carburetor Fig. 3 10 N·m (7 lb·ft) [1.0 kgf·m] 1-13 1-14 1-15A 1-15B 1-11 1-12 1-10 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty Carburetor Collar, 6.2-9-7.5 1-1 Main Nozzle 10 Collar, 6.2-9-7 1-2 Main Jet 11 Bolt 2 M6 L=85mm 1-3 Slow Jet 12 Washer...

  • Page 61: Inspection Items

    3. Inspection Items 1) Inspection of Fuel Feed System Piping Remove top cowl and check each section for fuel leak, dirt, deterioration and damages. Clean or replace parts if necessary. 4st 2/2.5/3.5 2007...

  • Page 62: Draining Fuel

    Fuel System (Carburetor) 2) Draining Fuel WARNING Remove fuel tank, fuel hose and carburetor after fully drain the fuel from these parts. 1 and use fuel pump to remove fuel. Remove fuel tank cap Set fuel cock knob 2 to full open position b. Place a piece of rag below the carburetor, and loosen c drain screw 3 to drain all fuel.

  • Page 63: Inspection Of Fuel Tank And Fuel Tank Cap

    3) Inspection of Fuel Tank and Fuel Tank Cap Check fuel tank and fuel tank cap for crack, leakage and damage. Replace if necessary. 4) Inspection of Fuel Cock Carburetor Check fuel cock for leakage. Tank 5) Inspection of Fuel Filter Check fuel filter (fuel cock ) for dirt and clogging, and clean if necessary.

  • Page 64: Inspection Of Carburetor

    Fuel System (Carburetor) 6) Inspection of Carburetor Check air and fuel passages for dirt in the jet and foreign substances. Clean carburetor body with cleaning fluid. Squirt all passages and jet with compressed air. CAUTION · Point the compressed air downward, taking care that detergent and dust do not enter the eyes and do not damage small parts of the carburetor.

  • Page 65: Assembling Of Carburetor

    Measure height a of float 4. Adjust height a of float 4 by bending tab b if the height is out of specified range. Float Height a : 9.0 - 10.0 mm (0.354 - 0.394 in) · Bring tab b of float 4 into light contact with top of float valve 5.

  • Page 66: Assembling Carburetor

    Fuel System (Carburetor) 8) Assembling Carburetor Attach carburetor ass'y to intake manifold. Carburetor Bolt : 6N · m (4 lb · ft) [0.6kgf · m] Put carburetor gaskets 1 and 3 and insulator 2 together with their projections a at the same side, and install carburetor.

  • Page 67: Adjustment Of Throttle Cable

    9) Adjustment of Throttle Cable Turn throttle grip 1 to full close position a. Pull choke rod 2 fully d. Attach throttle cable 3 to throttle drum 4 taking care of the positions of low speed side e and high speed side f. Pull outer cable g of throttle cable 3 to the side shown with the arrow by hand, and lock it with the nut while applying tension to the cable.

  • Page 68: Inspection Of Idle Engine Speed

    Fuel System (Carburetor) 10) Inspection of Idle Engine Speed Start engine and run for 5 minutes to warm up. Check idle engine speed. · Use tachometer to measure after warm up operation. · Set the measurement mode to 4 stroke 2 cylinder ·...

  • Page 69: Power Unit

    Power Unit Special Tools ……………………………… 5-2 18) Inspection of Cylinder Inner Diameter … 5-22 Parts Layout………………………………… 5-3 19) Inspection of Piston Clearance ………… 5-22 Engine ………………………………………… 5-3 20) Inspection of Piston Ring Side Clearance … 5-23 Recoil Starter ………………………………… 5-4 21) Inspection of Piston Rings ………………...

  • Page 70: Special Tools

    Power Unit 1.Special Tools Thickness Gauge Compression Gauge Valve Spring Compressor Attachment Flywheel Holder P/N. 353-72251-0 P/N. 3AC-99030-0 P/N. 3AB-99076-0 P/N. 3AC-99200-0 Removing or installing valve Measuring compression Removing or installing Measuring gaps pressure springs flywheel 3B7-72783-0 3B7-72784-0 Flywheel Puller Kit P/N.

  • Page 71: Parts Layout

    2.Parts Layout Engine 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 1342 1107 1107 1107 6 N·m (4 lb·ft) [0.6 kgf·m] 1107 1107 1342 1342 1342 Ref. Part Name Remarks Q'ty Power Unit Gasket...

  • Page 72: Recoil Starter

    Power Unit Recoil Starter P/L Fig. 8 6 N·m (4 lb·ft) [0.6 kgf·m] 1-11 1-12 1-10 5 N·m (4 lb·ft) [0.5 kgf·m] Ref. Ref. Remarks Part Name Remarks Part Name Q'ty Q'ty Recoil Starter 1-12 Starter Seal Do not reuse. 1-1 Starter Spring Bolt 3 M6 L=60mm...

  • Page 73: Oil Pan

    Oil Pan P/L Fig. 4 6 N·m (4 lb·ft) [0.6 kgf·m] 4st OIL 18 N·m (13 lb·ft) [1.8 kgf·m] 4st OIL 6 N·m ( 4 lb·ft) [0.6 kgf·m] 2 8.8 N·m (6.5 lb·ft) [0.9 kgf·m] 6 N·m ( 4 lb·ft) [0.6 kgf·m] 2 8.8 N·m (6.5 lb·ft) [0.9 kgf·m] 4st OIL 4st OIL...

  • Page 74: Cylinder

    Power Unit P/L Fig. 1 Cylinder 6 N·m (4 lb·ft) [0.6 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.3-7 6 N·m ( 4 lb·ft) [0.6 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 2 8.8 N·m (6.5 lb·ft) [0.9 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 4st OIL 4st OIL...

  • Page 75: Cam Shaft & Valve

    P/L Fig. 5 Cam Shaft & Valve 4st OIL 4st OIL 4st OIL 25 N·m (18 lb·ft) [2.5 kgf·m] 4st OIL 10 N·m (7 lb·ft) [1.0 kgf·m] 4st OIL 4st OIL 4st OIL 4st OIL 4st OIL mark A-view 4st OIL Ref.

  • Page 76: Piston & Crank Shaft

    Power Unit P/L Fig. 2 Piston & Crank Shaft 4st OIL 4st OIL 4st OIL 4st OIL 1 5 N·m (4 lb·ft) [0.5 kgf·m] mark 2 10 N·m (7 lb·ft) [1.0 kgf·m] 4st OIL 4st OIL Ref. Part Name Remarks Q'ty Crankshaft Ass'y with Gear...

  • Page 77: Inspection Items

    3. Inspection Items 1) Inspection of Compression Pressure Start and idle engine for 5 minutes to warm up, and then stop. Shift gear into neutral (N). Remove lock plate (of stop switch lanyard) from stop switch. CAUTION To prevent accidental start of the engine, remove lock plate (of stop switch lanyard) from stop switch before measuring compression pressure.

  • Page 78: Inspection Of Valve Clearance

    Power Unit 2) Inspection of Valve Clearance Disconnect plug cap 1 connection, and then, remove spark plug and cylinder head cover 2. When removing or installing cylinder head cover without removing power unit, use 10 mm box wrench with large offset angle. Pull recoil starter 3 to turn flywheel clockwise until flywheel "T"...
  • Page 79 Loosen pivot lock nut 5 and then turn the pivot 6 so that valve clearance reaches specified value. · Turning pivot 6 clockwise makes valve clearance smaller. · Turning pivot 6 counterclockwise makes valve clearance larger. Tighten pivot lock nut 5 to specified torque, and check valve clearance again.

  • Page 80: Removing Power Unit

    Power Unit 3) Removing Power Unit Turn fuel cock 1 to OFF and remove fuel tank ass'y 2 and fuel cock ass'y 1. Remove choke cable 4 from carburetor 3. Turn throttle grip to full close position, and disconnect throttle cables 6 (2 pcs.) from throttle drum 5. Remove bolt 7 and disconnect leads (black) 8 of igniter and stop switch.

  • Page 81: Removal And Disassembly Of Crank Case Head

    4) Removal and Disassembly of Crank Case Head Remove bolts and remove crank case head ass'y. Remove O ring. Do not reuse. Remove oil seal. Do not reuse. 4st 2/2.5/3.5 2007 5-13...

  • Page 82: Inspection Of Crank Case Head

    Power Unit 5) Inspection of Crank Case Head Check crank case head for crack, damage and corrosion. Replace if necessary. 6) Assembly of Crank Case Head Attach new oil seal 1 to crank case head by using a commercially available mandrel. Apply lithium grease to the lip of oil seal.

  • Page 83: Disassembly Of Power Unit

    8) Disassembly of Power Unit Place power unit on the work bench a. Remove recoil starter 1 and flywheel cover 2. Remove flywheel nut 3. Flywheel Holder 4 : P/N. 3AC-99200-0 CAUTION Apply forces to tools toward directions as shown, and perform work taking care not to allow flywheel holder to slip.
  • Page 84 Power Unit Remove bolts, and then igniter 7. Remove breather pipe 8. Remove intake manifold 9 and carburetor 0. Remove throttle cable bracket q. 5-16 4st 2/2.5/3.5 2007...

  • Page 85: Removal Of Rocker Arm

    9) Removal of Rocker Arm Remove bolts and then cylinder head cover. Remove lock nut 1, and then pivot 2, rocker arm 3 and push rod 4. Remove pivot bolt 5, and then push rod plate 6. 4st 2/2.5/3.5 2007 5-17...

  • Page 86: Inspection Of Rocker Arm And Pivot

    Power Unit 10) Inspection of Rocker Arm and Pivot Check rocker arm 1 and pivot 2 for crack, wear and damage. Replace if necessary. 11) Inspection of Push Rod Plate Check push rod plate for crack and damage. Replace if necessary.

  • Page 87: Disassembly Of Cylinder Block

    13) Disassembly of Cylinder Block Remove thermostat cap bolts, and then thermostat cap and thermostat. Remove breather cover. Loosen oil pan bolts in the order reverse to the numbers shown, and remove oil pan. 8 - 1 Wipe off spilled oil completely. Loosen crank case bolts in the order reverse to the numbers shown, and remove crank case.

  • Page 88: Inspection Of Slinger (Splash Lubrication)

    Power Unit 14) Inspection of Slinger Splash Lubrication Adopts splash lubrication system that is simple in structure. Slinger is driven by the gear of crank shaft, and splashes oil collected in oil pan over the crank case parts. Check slinger for crack, damage and wear. Replace if necessary.

  • Page 89: Inspection Of Cam Shaft

    16) Inspection of Cam Shaft Check cam shaft gear and decompressor for damage and wear. Replace if necessary. Measure cam height. Replace if the diameter is less than specified value. Cam Height a, both intake and exhaust : Standard value 24.04 mm (0.9464 in) Functional Limit : 23.78 mm (0.9362 in)

  • Page 90: Inspection Of Piston Outer Diameter

    Power Unit 17) Inspection of Piston Outer Diameter Measure piston outer diameter between points specified. Replace if it is less than specified value. Piston Outer Diameter a : Standard value 54.96 mm (2.1638 in) Measuring Point b : 7mm (0.28 in) upward from the bottom of piston skirt Functional Limit : 54.90 mm (2.1614 in) 18) Inspection of Cylinder Inner Diameter...

  • Page 91: Inspection Of Piston Ring Side Clearance

    20) Inspection of Piston Ring Side Clearance Measure piston ring side clearance. Replace piston and piston rings as a set if the clearance is over specified value. Piston Ring Side Clearance : Top Ring a : 0.04 - 0.08mm (0.0016 - 0.0031 in) Second Ring b : 0.03 - 0.07mm (0.0012 - 0.0028 in) Oil Ring c : 0.05 - 0.15mm (0.0020 - 0.0059 in) Functional Limit...

  • Page 92: Inspection Of Piston Pin

    Power Unit 22) Inspection of Piston Pin Measure piston pin outer diameter. Replace if it is less than specified value. Piston Pin Outer Diameter : Standard value 14.00 mm (0.5512in) Functional Limit : 13.97 mm (0.5500 in) Measure piston pin boss inner diameter a. Obtain clearance between piston pin and pin boss.

  • Page 93: Inspection Of Connecting Rod Big End Side Clearance

    25) Inspection of Connecting Rod Big End Side Clearance Measure connecting rod big end side clearance a by using a commercially available thickness gauge. Replace connecting rod and/or crank shaft if the clearance is over specified value. Connecting Rod Big End Side Clearance a : 0.10 - 0.25 mm (0.0039 - 0.0098 in) Functional Limit : 0.60 mm (0.0236 in)

  • Page 94: Disassembly And Assembly Of Crank Shaft

    Power Unit 27) Disassembly and Assembly of Crank Shaft Remove bearing 1 from crank shaft by using a commercially available bearing puller. CAUTION Do not reuse removed bearing. Replace with new one. Only flywheel side bearing 1 can be replaced. Do not reuse.

  • Page 95: Inspection Of Crank Pin Oil Clearance

    28) Inspection of Crank Pin Oil Clearance Clean crank shaft 1 and connecting rod parts 2 and 3. Place cylinder block upside down on the work bench. Install piston 4 to connecting rod 2, and then, install the assembly to cylinder block. Do not attach piston rings in this step.

  • Page 96: Installation Of Piston And Connecting Rod

    Power Unit 29) Installation of Piston and Connecting Rod Install connecting rod 2, piston pin 3, and piston pin clip 4 to piston 1. · Point "3AB-UP" mark a of connecting rod and "UP" mark b of piston to the same direction. ·...

  • Page 97: Removal Of Valves And Springs

    30) Removal of Valves and Springs Place cylinder block on the work bench 1. Push in valve spring retainer 2 by using valve spring compressor attachment 3, remove cotter pin 4, and then, remove spring 5 and valve 6. Valves, springs and other related parts should be arranged in the order they are removed.

  • Page 98: Inspection Of Valve

    Power Unit 32) Inspection of Valve Check valve for dent and wear on the face. Replace if necessary. Measure valve stem outer diameter a. Replace if it is less than specified value. Valve Stem Outer Diameter a : Standard value Intake Side (IT) : 5.47 mm (0.2154 in) Exhaust Side (E) : 5.46 mm (0.2150 in)

  • Page 99: Inspection Of Valve Seat

    34) Inspection of Valve Seat Remove carbon built up on the valve. Apply thin coat of red lead on the valve seat. Use valve lapper 1 (commercially available item) as shown to push valve 2 onto valve seat lightly. Measure width of area where valve face contacted with valve seat a that can be identified with red lead adhered to valve face.

  • Page 100: Correction Of Valve Seat

    Power Unit 35) Correction of Valve Seat Use valve seat cutter 1 (commercially available item) to correct valve seat. 0û 45û 60û Turn 45 degree cutter clockwise to cut valve seat surface to make it smooth. 45˚ Be careful not to over-cut valve seat. Turn valve seat cutter while pushing down evenly.
  • Page 101 Use 45 degree cutter to adjust contact width of valve seat c to specified value. 45˚ b Width before correction c Specified width Valve seat contact area is located on the center, which should be adjusted to specified value by cutting upper and 30˚...
  • Page 102 Power Unit Apply thin coat of abrasive compound on the overall valve seat contact area, and turn valve lapper 1 (commercially available item) while tapping valve. CAUTION Perform the work by taking care not to allow abrasive compound to adhere to valve stem and valve guide.

  • Page 103: Installation Of Valves

    36) Installation of Valves Place cylinder block on the work bench. Apply oil to valve guide and attach new valve stem seal 1. 4st OIL Intake Side : Black Exhaust Side : Green Do not reuse the seal. Use new one. Do not reuse.

  • Page 104: Assembly Of Cylinder And Crank Case

    Power Unit 37) Assembly of Cylinder and Crank Case Place cylinder block upside down on the work bench. Bring piston crown 1 "UP" mark to flywheel side ←, set piston ass'y 3 on the cylinder block 2 to assemble. Before assembling, apply engine oil to piston peripheral surfaces, piston rings and cylinder liner.
  • Page 105 Install lifter q to cylinder block. 4st OIL Install cam shaft w to cylinder block 2 as shown. Bring crank shaft mark d to cam shaft w mark 4st OIL Apply 4 stroke engine oil to crank shaft and cam shaft. Apply Loctite 518 to crank case e mating face (one side) with width of 1.0 mm (0.04 in).

  • Page 106: Assembly To Power Unit

    Power Unit Attach dowel pin, new gasket and thrust plate. Install oil pan r and tighten bolts to specified torque. Do not reuse removed gasket. Replace with new one. Oil Pan Bolts : 1 - 8 1st tightening torque : 6 N · m (4 lb · ft) [0.6 kgf · m] 2nd tightening torque : 8.8 N ·...
  • Page 107 38) Assembly to Power Unit Install thermostat 1, new gasket and thermostat cover 2. Install breather cover 3. Install throttle cable bracket 4. Thermostat Cap Bolts : Breather Cover Bolts : Throttle Cable Bracket Bolts : 6 N · m (4 lb · ft) [0.6 kgf · m] a bGaskets Do not reuse.

  • Page 108: Assembly Of Rocker Arm

    Power Unit 39) Assembly of Rocker Arm Direct magneto key groove 1 to piston top dead center. Set piston to top dead center of compression stroke. Remove oil filler cap and check that ø5mm (0.2 in) hole a of cam shaft gear 2 can be seen. Install push rod plate 3 and tighten pivot bolt 4 to specified torque.

  • Page 109: Assembly Of Power Unit

    40) Assembly of Power Unit Apply ThreeBond 1107 to both faces of new gasket, and attach dowel pins 3 (2 pcs.) and gasket 1. Install power unit 3, and tighten bolts 4 (7 pcs.) in two or three steps to specified torque. Power Unit Installation Bolt : 1107 1107...

  • Page 110: Disassembly Of Recoil Starter

    Power Unit 41) Disassembly of Recoil Starter Remove bolts and recoil starter and flywheel cover ass'y. Put rope in the groove a of reel 1 and gently turn reel 1 clockwise b to release tension of starter spring. 1 Reel Remove starter shaft screw 4, and then, friction plate 3, ratchet and spring 2.

  • Page 111: Assembly Of Recoil Starter

    43) Assembly of Recoil Starter Reverse disassembly procedure to assemble by taking care of the following matters. When setting starter spring into reel 1, face starter spring outer edge hook to the right and set it into peripheral cut of starter case.

  • Page 112: Lower Unit

    Lower Unit Special Tools ……………………………… 6-2 16) Removing Clutch Cam and Cam Rod ……… 6-13 Parts Layout………………………………… 6-3 17) Disassembly of Clutch Cam and Cam Rod … 6-13 Drive Shaft Housing & Gear Case…………… 6-3 18) Inspection of Clutch Cam and Cam Rod …… 6-13 Gear Case (Drive Shaft) ………………………...

  • Page 113: Special Tools

    Lower Unit 1. Special Tools Spring Pin Tool A Spring Pin Tool B Center Plate 3 Driver Rod 3 P/N. 345-72227-0 P/N. 345-72228-0 P/N. 3AB-99701-0 P/N. 3AB-99702-0 Used in combination with driver rod and Used in combination with center plate and Removing spring pin Installing spring pin bearing attachment to locate lower gear...

  • Page 114: Parts Layout

    P/L Fig. 9 2. Parts Layout Drive Shaft Housing & Gear Case 1107 1107 1107 6 N·m (4 lb·ft) [0.6 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] 5 N·m (4 lb·ft) [0.5 kgf·m] 1342 1342 1342 1342...

  • Page 115: Gear Case (Drive Shaft)

    Lower Unit P/L Fig. 10 Gear Case (Drive Shaft) 17-1 4st OIL 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 4st OIL GEAR GEAR GEAR 4st OIL GEAR GEAR GEAR 1342 b Note: Marked with "SH2 C3" a Projection 1342 1342 Ref.

  • Page 116: Gear Case (Propeller Shaft)

    P/L Fig. 11 Gear Case (Propeller Shaft) GEAR GEAR GEAR 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 GEAR GEAR GEAR GEAR GEAR GEAR 1342 1342 1342 Ref. Description Remarks Q'ty Ball Bearing, 6004 Do not reuse. Forward Gear( "A"Gear) Shim, 21-28-0.1 Shim, 21-28-0.15 Propeller Shaft...

  • Page 117: Shift

    Lower Unit P/L Fig. 12 Shift 4 N·m (3 lb·ft) [0.4 kgf·m] 1342 1342 1342 6 N·m (4 lb·ft) [0.6 kgf·m] GEAR GEAR GEAR GEAR GEAR GEAR 1342 1342 1342 Ref. Description Remarks Q'ty Shift Lever O-Ring, 1.9-6.8 Do not reuse. Ceramic Ball, 7.7 Shift Lever Stopper Spring Washer, 10.5-18-1.5...

  • Page 118: Inspection Item

    3. Inspection Item 1) Draining Gear Oil Set outboard motor vertical. 2 and then 1 to drain gear oil. Refer to Remove oil plugs "Replacement of Gear Oil" in Chapter 3. Remove lower oil plug 1 first. 3 Gasket Do not reuse. 2) Removing Propeller Shift gear into neutral (N).

  • Page 119: Removing Lower Unit

    Lower Unit 3) Removing Lower Unit Removal of lower unit does not require removal of power unit from outboard motor body. Tilt up and lock with tilt stopper. Remove grommet 1 and loosen bolt 2. Bolt 2 should be loosened, not removed from joint 3.

  • Page 120: Inspection Of Water Pump

    5) Inspection of Water Pump Check upper pump case (upper) 1 for deformation. Replace if necessary. Check impeller 2 and pump case liner 3 for cracks and wear. Replace if necessary. Check key 4 and drive shaft installation face a for wear. Replace if necessary.

  • Page 121: Removing Propeller Shaft Housing Ass'y

    Lower Unit 6) Removing Propeller Shaft Housing Ass'y Remove bolt 1 and pull out propeller shaft housing ass'y 2. When the ass'y is pulled off a little, put bladed screw driver 3 in the mating surface of lower gear case to separate it from the case. Remove propeller shaft ass'y.

  • Page 122: Disassembly Of Propeller Shaft Ass'y

    9) Assembly of Propeller Shaft Ass'y Put clutch spring 1 and attach clutch 3 to propeller shaft 2. When installing clutch 3, push down clutch spring 1 by using a bladed screw driver 4. 10) Disassembly of Propeller Shaft Housing Remove bearing 1 by using commercially available bearing puller.

  • Page 123: Assembly Of Propeller Shaft Housing

    Lower Unit 12) Assembly of Propeller Shaft Housing Apply gear oil to outside of new oil seal 1, and attach it to propeller shaft housing 3 by using a commercially available mandrel 2. GEAR GEAR GEAR Do not reuse. Install new bearing 4 to propeller shaft housing 3. Do not reuse removed bearing.

  • Page 124: Assembly Of Pump Case (Lower)

    15) Assembly of Pump Case (Lower) Apply gear oil to outside of new oil seal 1, and attach it to pump case (lower) 3 with numbered side down by using a commercially available mandrel 2. GEAR GEAR Apply OBM grease to lip of oil seal 1. GEAR Do not reuse.

  • Page 125: Removing Drive Shaft

    Lower Unit 20) Removing Drive Shaft Pull up drive shaft ass'y 1, remove pinion (B) gear 2 , and pull out forward (A) gear 3. · When removing forward (A) gear, be careful not to damage the existing shims or lose them. Shim is reusable.

  • Page 126: Inspection Of Forward Gear And Pinion Gear (A And B Gears)

    23) Inspection of Forward Gear and Pinion Gear (A and B Gears) Check teeth and jaw of forward (A) gear and pinion (B) gear and jaw of clutch for cracks and wear. Replace if necessary. 24) Assembly of Drive Shaft Use a press device to install new drive shaft bearing 1 to drive shaft 2 with the numbered side up.

  • Page 127: Disassembly Of Gear Case

    Lower Unit 25) Disassembly of Gear Case Check bearings 1 and 2 for cracks and generation of abnormal noise. Replace if necessary. CAUTION Do not reuse removed bearing. · Do not remove bearing unless it is replaced with new one. ·...

  • Page 128: Inspection Of Gear Case

    26) Inspection of Gear Case Check skeg area a and torpedo-like front area b for cracks and damage. Replace if necessary. 27) Assembly of Gear Case Do not reuse removed bearing. Install bearing 1 with numbered side up to gear case 2 to specified depth.

  • Page 129: Installation Of Clutch Cam And Cam Rod

    Lower Unit 28) Installation of Clutch Cam and Cam Install cam rod ass'y 1 to gear case as shown. GEAR GEAR GEAR Be careful of direction of cam rod. 29) Installation of Forward Gear and Pinion Gear (A and B Gears) Install removed shims and forward (A) gear 1 , and then, drive shaft ass'y 2 and pinion (B) gear 3.

  • Page 130: Installation Of Water Pump

    31) Installation of Water Pump Attach new gaskets 1 and 2, water pump guide plate 3 and dowel pin 4. a Projection 1 and 2 Do not reuse. Attach key 5 to drive shaft. Bring impeller 6 groove b to key 5 and install impeller to drive shaft.

  • Page 131: Installation Of Propeller Shaft Housing

    Lower Unit Install pump case (upper) ass'y 8 on the gear case, and tighten bolts 0 in two or three steps to specified torque. Apply grease to interior of pump case liner, and install pump case (upper) by pushing it down 1342 1342 1342...

  • Page 132: Filling With Gear Oil

    33) Filling with Gear Oil Feed gear oil to specified quantity 2. "Refer to Chapter 3." GEAR GEAR GEAR Perform "Inspection of Gear Case (Leakage)" in Chapter 3 if necessary. 3 Gasket Do not reuse. GEAR GEAR GEAR 3 Gasket Do not reuse.
  • Page 133 Lower Unit Attach lower unit ass'y to drive shaft housing, and tighten lower unit installation bolts 2 (nut 3 ) to specified torque. · Connect water pipe securely. · Move flywheel a little to align the drive shaft spline to crank shaft spline. Lower Unit Installation Bolts 2 : 1342 10 N ·...
  • Page 134 Bracket Parts Layout………………………………… 7-2 Assembling Procedure ………………… 7-7 Clamp Bracket & Swivel Bracket …………… 7-2 1) Assembly of Clamp Bracket …………… 7-7 Drive Shaft Housing & Gear Case…………… 7-3 2) Installation of Steering Stopper ………… 7-7 Shift……………………………………………… 7-4 3) Installation of Drive Shaft Housing……… 7-8 Tiller Handle &...

  • Page 135: Parts Layout

    Bracket P/L Fig. 13 1. Parts Layout Clamp Bracket & Swivel Bracket 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 10 N·m (7 lb·ft) [1.0 kgf·m] 1342 1342 1342 1342 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 7 N·m (5 lb·ft) [0.7 kgf·m] 1342 1342 1342...

  • Page 136: Drive Shaft Housing & Gear Case

    P/L Fig. 9 Drive Shaft Housing & 26-1 Gear Case 4st OIL 1107 1107 1107 6 N·m (4 lb·ft) [0.6 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] 5 N·m (4 lb·ft) [0.5 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] 1342 1342 4st OIL 1342...

  • Page 137: Shift

    Bracket P/L Fig. 12 Shift 4 N·m (3 lb·ft) [0.4 kgf·m] 1342 1342 1342 6 N·m (4 lb·ft) [0.6 kgf·m] GEAR GEAR GEAR GEAR GEAR GEAR 1342 1342 1342 Ref. Part Name Remarks Q'ty Shift Lever O-Ring, 1.9-6.8 Do not reuse. Ceramic Ball, 7.7 Shift Lever Stopper Spring Washer, 10.5-18-1.5...

  • Page 138: Tiller Handle & Throttle

    P/L Fig. 7 Tiller Handle & Throttle 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.1-18 6 N·m (4 lb·ft) [0.6 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] a Adjust. Ref. Part Name Remarks Q'ty Tiller Handle Tiller Handle Bushing Cover Bolt 2 M6 L=16mm Grip Throttle Shaft Damper...

  • Page 139: Cowl

    Bracket P/L Fig. 15 Cowl 2 N·m (1.5 lb·ft) [0.2 kgf·m] 13-7 13-2 1342 1342 1342 13-3 13-4 13-5 13-6 13-6 13-6 13-6 6 N·m (4 lb·ft) [0.6 kgf·m] 13-1 1342 1342 1342 6 N·m (4 lb·ft) [0.6 kgf·m] 1342 1342 1342 1342...

  • Page 140: Assembling Procedure

    2. Assembling Procedure 1) Assembly of Clamp Bracket Attach distance piece 2 and bracket bolt 3 to clamp bracket 1. Assemble swivel bracket 4 and clamp bracket 5, thrust 1342 1342 1342 supporter 6,and tighten nylon nut 7 and nut 8 to specified torque.

  • Page 141: Installation Of Drive Shaft Housing

    Bracket 3) Installation of Drive Shaft Housing Install drive shaft housing 1 to swivel bracket 2 and tighten bolts 3 to specified torque. Swivel Bracket Bolts 3 : 10 N · m (7 lb · ft) [1.0 kgf · m] 1342 1342 1342...

  • Page 142: Installation Of Tiller Handle

    5) Installation of Tiller Handle Attach throttle cable 2 to throttle shaft 1 as shown. Install throttle shaft 1 with throttle cable 2 to tiller handle 3, and tighten screw 4 securely. Be careful of location of throttle friction 5. 5 Do not apply grease here.

  • Page 143: Adjustment Of Throttle Cable

    Bracket 6) Adjustment of Throttle Cable Turn throttle grip 1 to full close position a. Pull choke rod 2 fully d. Attach throttle cable 3 to throttle drum 4 taking care of positions of low speed side e and high speed side f. Pull outer cable g of throttle cable 3 to the side shown with the arrow by hand, and lock it with the nut while applying tension to the cable.
  • Page 144 Electrical System Special Tools ……………………………… 8-2 Ignition System and Ignition Control System … 8-4 Parts Layout………………………………… 8-3 1) Inspection of Ignition Spark……………… 8-4 Magneto ………………………………………… 8-3 2) Inspection of Plug Cap…………………… 8-5 3) Inspection of Igniter ……………………… 8-6 4) Inspection of Stop Switch ……………… 8-7...

  • Page 145: Electrical System

    Electrical System 1. Special Tools Spark Tester P/N. 3F3-72540-0 Inspecting sparks 4st 2/2.5/3.5 2007...

  • Page 146: Parts Layout

    2. Parts Layout P/L Fig. 6 Magneto 6 N·m (4 lb·ft) [0.6 kgf·m] 43 N·m (31 lb·ft) [4.3 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 2.3 N·m (1.7 lb·ft) [0.23 kgf·m] a Spark Plug b Igniter Clearance 0.2 - 0.4mm(0.008 - 0.016in) Ref.

  • Page 147: Ignition System And Ignition Control System

    Electrical System 3. Ignition System and Ignition Control System 1) Inspection of Ignition Spark Disconnect plug cap from spark plug. Connect plug cap to spark tester. Connect spark tester clip to spark plug tip electrode. Spark Tester: P/N. 3F3-72540-0 Spark Performance: 5mm (0.2in) or over 5 10 Start engine and check spark.

  • Page 148: Inspection Of Plug Cap

    2) Inspection of Plug Cap Remove the part and test it as a separate unit. Disconnect plug cap from spark plug. Remove plug cap from high tension cable. Measure plug cap resistance. Replace if other than specified value. Plug Cap Resistance (at 20˚C) : 3.0 - 7.0 kΩ...

  • Page 149: Inspection Of Igniter

    Electrical System 3) Inspection of Igniter Remove igniter, and turn plug cap counterclockwise to remove it from high tension cord. Measure igniter resistance. Replace if other than specified value. Remove the part and test it as a separate unit. Igniter Resistance (at 20˚C) : Secondary Coil:Between High Tension Cord and Black (B) 2.0 - 3.0 kΩ...

  • Page 150: Inspection Of Stop Switch

    4) Inspection of Stop Switch Check conduction of stop switch, and replace if not conductive. This test can be made without removing parts. Lead Wire Color Switch Position Brown (Br) Black (B) Remove lock plate. Attach lock plate. b Press switch.
  • Page 151 Troubleshooting Troubleshooting List …………………… 9-2 Ignition System …………………… 9-6 Power Unit ………………………………… 9-3 Compression Pressure…………… 9-7 Trouble 3 Idle engine speed will not stabilize. … 9-8 Trouble 1 Engine will not start or is a little hard to start. (Recoil starter operates normally.) ………… 9-3 Trouble 4 Rough acceleration.

  • Page 152: Troubleshooting

    Troubleshooting 1.Troubleshooting List Probable Cause ○ ○ Fuel level is low in the tank. ○ ○ ○ ○ ○ ○ ○ Fuel system connection is incomplete. ○ ○ ○ ○ ○ ○ ○ Fuel pipe is twisted. ○ ○ ○ ○...

  • Page 153: Power Unit

    Before working on the outboard motor, check the hull, rigging, installation of outboard motor, fuel level, and wire connections. For mechanical troubleshooting, refer to relevant troubleshooting section in this chapter. For checking and servicing outboard motor, refer to service procedures described in this manual to perform the work safely.
  • Page 154 Troubleshooting Check valve clearance. Adjust valve clearance. Normal ? Check valves, cylinder block and/or piston ass’y. 4st 2/2.5/3.5 2007...

  • Page 155: Trouble 2 Engine Starts But Stalls Soon

    Trouble 2 Engine starts but stalls soon. • Inspection of Fuel System, Ignition System, Compression Pressure Fuel System Check air vent screw of fuel tank. Open air vent screw. Open? Check if fuel contains water and fuel filter is clogged. Check fuel hose for bend Does fuel contains water, and fuel leak.

  • Page 156: Ignition System

    Troubleshooting Ignition System Use spark tester to check ignition sparks. Check igniter Normal ? and/or plug cap. WARNING • When testing, put electrode cap assuredly to prevent Replace spark plug direct contact with spark tester wiring and leak of with new one. electrical current.

  • Page 157: Compression Pressure

    Compression Pressure Check if secondary air is sucked through mating surface of carburetor or intake manifold. Check compression Is secondary air pressure. sucked? Replace defective part and seal with new ones. 4st 2/2.5/3.5 2007...

  • Page 158: Trouble 3 Idle Engine Speed Will Not Stabilize

    Troubleshooting Trouble 3 Idle engine speed will not stabilize. • Inspection of Intake Manifold, Air Intake System and Ignition System Check operations of throttle cable and drum. Normal ? Adjust throttle cable. Check ignition timing. Check gaskets Out of specified if secondary air is range? sucked through them.

  • Page 159: Trouble 4 Rough Acceleration

    Trouble 4 Rough acceleration. Rapid opening of throttle causes engine to stall. Acceleration is not smooth. Inspection of Carburetor, Ignition System and Compression Pressure • Check operation of throttle cable. Is the throttle Adjust throttle cable. valve tuned ? Disassemble carburetor, and check internal components for clogging, dirt and damage.

  • Page 160: Trouble 5 Gear Shifting Cannot Be Made Normally

    Troubleshooting Trouble 5 Gear shifting cannot be made normally. Check operations of shift lever. Normal ? Check spring and ball. Check shift rod joint. Normal ? Replace shift rod. Disassemble lower unit and check operation of clutch. Replace defective part Normal ? with new one.
  • Page 161 Copyright © 2007 Tohatsu Corporation. All rights reserved. No part of this manual may be reproduced or transmitted in any form or by any means without the express written permission of Tohatsu Corporation.
  • Page 162 OB No.003-21058-0 07-04 NB-2600 Printed in Japan...

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