Yamaha F2.5C Page 106 Service Manual Download

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POWR

Power unit

5-45

6D55F11

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
piston rings before installation.

Install half of the main bearings

into

the cylinder block

NOTE:

• Install the main bearings in their original

positions.

• Insert the projection

of each bearing into

the slots in the cylinder block.

Install the balancer rod onto the crank-
shaft.

Set the crankshaft

and oil seals

and

into the cylinder block as shown.

NOTE:

Apply engine oil to the inner oil seals before
installation.

Install the connecting rod caps

to the

connecting rods, and then tighten the
connecting rod bolts to the specified
torques in two stages.

NOTE:

• Align the alignment marks

on the con-

necting rod cap and connecting rod.

• Apply engine oil to the connecting rod bolts

before installation.

Piston slider: 90890-06529

S6D55920

Connecting rod bolt:

1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb)
2nd: 17 N·m (1.7 kgf·m, 12.5 ft·lb)

S6D55950

Summary of Contents for F2.5C

Page 1: ...F25C SERVICE MANUAL 6D5 28197 5F 11 290539 ...

Page 2: ... modifications and significant changes in specifications and procedures and these are incorporated in successive editions of this manual Important information 1 Particularly important information is distinguished in this manual by the following notations The Safety Alert Symbol means ATTENTION BECOME ALERT YOUR SAFETY IS INVOLVED WARNING Failure to follow WARNING instructions could result in sever...

Page 3: ...nformation 1 GEN INFO Specifications 2 SPEC Periodic checks and adjustments 3 CHK ADJ Fuel system 4 FUEL Power unit 5 POWR Lower unit 6 LOWR Bracket unit 7 BRKT Electrical systems 8 ELEC Troubleshooting 9 TRBL SHTG Index ...

Page 4: ......

Page 5: ...1 5 Serial number 1 5 Propeller selection 1 5 Propeller size 1 5 Selection 1 6 Predelivery checks 1 6 Checking the fuel system 1 6 Checking the engine oil level 1 6 Checking the gear oil level 1 6 Checking the outboard motor mounting height 1 7 Checking the remote control cables remote control model 1 7 Checking the steering system 1 8 Checking the gear shift and throttle operation 1 8 Checking th...

Page 6: ...Not reusable 6 Dowel pin 2 7 Bolt 4 M10 40 mm 8 Drain screw 1 9 Grommet 1 10 Bolt 1 M10 45 mm 11 Bolt 1 M8 60 mm 12 Thrust washer 1 13 Propeller 1 14 Washer 1 15 Washer 1 16 Cotter pin 1 Not reusable 17 Propeller nut 1 18 Trim tab 1 LOWR Lower unit 6 19 62Y5A11 Removing the drive shaft 1 Remove the drive shaft assembly and pinion and then pull out the forward gear Disassembling the drive shaft 1 I...

Page 7: ...c current Symbols 7 to C in an exploded diagram indicate the grade of lubricant and the lubrication point 7 Apply Yamaha 4 stroke motor oil 8 Apply gear oil 9 Apply water resistant grease Yamaha grease A 0 Apply molybdenum disulfide grease A Apply corrosion resistant grease Yamaha grease D B Apply low temperature resistant grease Yamaha grease C C Apply injector grease Symbols D to I in an explode...

Page 8: ...sing an air compressor Protect your hands and feet by wearing pro tective gloves and safety shoes when neces sary 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 Under normal conditions the lubricants men tioned in this manual should not harm or be hazardous to your skin However you s...

Page 9: ...e center and moving outward Non reusable parts Always use new gaskets seals O rings cot ter pins circlips etc when installing or assembling parts Disassembly and assembly 1 Use compressed air to remove dust and dirt during disassembly 2 Apply engine oil to the contact surfaces of moving parts before assembly 3 Install bearings with the manufacture identification mark in the direction indi cated in...

Page 10: ...ly affect boat speed acceleration engine life fuel economy and even boating and steering capabilities An incorrect choice could adversely affect performance and could also seriously damage the engine Use the following information as a guide for selecting a propeller that meets the operating conditions of the boat and the outboard motor Propeller size The size of the propeller is indicated on a pro...

Page 11: ...hat the fuel hoses are securely connected and that the fuel tank is full with fuel CAUTION This is a 4 stroke engine Never use pre mixed fuel Checking the engine oil level 1 Check the engine oil level NOTE If the engine oil is below the minimum level mark b add sufficient oil until the level is between a and b Checking the gear oil level 1 Check the gear oil level Propeller size in Material 9 7 8 ...

Page 12: ...optimum mounting height is affected by the combination of the boat and the outboard motor To determine the optimum mounting height test run the outboard motor at differ ent heights 2 Check that the clamp brackets are secured with the clamp screws Checking the remote control cables remote control model 1 Set the remote control lever to the neu tral position and fully close the throttle lever 2 Chec...

Page 13: ...eered Checking the gear shift and throttle operation 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 2 Check that the throttle operates smoothly when the throttle grip tiller handle model is turned from the fully closed position to the fully open position a Check that the throttle operates smoothly when the r...

Page 14: ...om the cooling water pilot holes Test run 1 Start the engine and then check that the gear shift operates smoothly 2 Check the engine idle speed after the engine has been warmed up 3 Operate at trolling speed 4 Run the outboard motor for 1 hour at 2 000 r min or at half throttle then for another hour at 3 000 r min or at 3 4 throttle 5 Check that the outboard motor does not tilt up when shifting in...

Page 15: ...r min or 3 4 throttle and 1 minute out of every 10 at full throt tle 3 Eight hours c at any speed however avoid running at full speed for more than 5 minutes È Hour After test run 1 Check for water in the gear oil 2 Check for fuel leakage in the cowling 3 Flush the cooling water passage with fresh water using the flushing kit and with the engine running at idle S69J1240 0 1 2 10 È a b c Predeliver...

Page 16: ...GEN INFO General information 1 11 6D55F11 MEMO ...

Page 17: ... 2 3 4 5 6 7 8 9 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 ...

Page 18: ...t 5 500 r min Full throttle operating range r min 5 000 6 000 Maximum fuel consumption L US gal lmp gal hr 9 2 2 4 2 0 at 6 000 r min Engine idle speed r min 925 1 025 Power unit Type In line 4 stroke SOHC 4 valves Cylinder quantity L2 Total displacement cm3 cu in 498 30 4 Bore stroke mm in 65 0 75 0 2 56 2 95 Compression ratio 9 87 Control system Tiller handle Remote control Starting system Manua...

Page 19: ...ent L US qt lmp qt 1 9 2 0 1 7 Gear oil type Hypoid gear oil Gear oil grade 2 API SAE GL 4 90 Gear oil quantity cm3 US oz lmp oz 320 10 8 11 3 Bracket unit Tilt angle at 12 boat transom Degree 8 12 16 20 24 Tilt up angle Degree 64 Shallow water drive angle Degree 29 43 Steering angle Degree 45 45 Drive unit Gear shift positions F N R Gear ratio 2 08 27 13 Reduction gear type Spiral bevel gear Clut...

Page 20: ...s Piston diameter D mm in 64 950 64 965 2 5571 2 5577 Measuring point H mm in 2 0 0 08 Piston to cylinder clearance mm in 0 035 0 065 0 0014 0 0026 Piston pin boss bore mm in 15 974 15 985 0 6289 0 6293 Oversize piston diameter 1st mm in 65 200 65 215 2 5669 2 5675 2nd mm in 65 450 65 465 2 5768 2 5774 Piston pins Outside diameter mm in 15 965 15 970 0 6285 0 6287 1 Measure conditions Ambient temp...

Page 21: ... 48 0 0929 0 0976 Dimension T mm in 2 75 0 1083 End gap mm in 0 20 0 70 0 0079 0 0276 Side clearance mm in 0 04 0 18 0 0016 0 0070 Oversize diameter 1st mm in 65 250 2 5689 2nd mm in 65 500 2 5787 Camshafts Intake and exhaust A mm in 30 834 31 034 1 2139 1 2218 Intake and exhaust B mm in 25 90 26 10 1 0197 1 0276 Camshaft journal diameter top mm in 36 925 36 945 1 4537 1 4545 Camshaft journal diam...

Page 22: ...65 0 2170 Stem to guide clearance Intake and exhaust mm in 0 025 0 052 0 0010 0 0020 Stem runout limit mm in 0 03 0 0012 Valve springs Free length mm in 39 85 1 5689 Minimum free length mm in 25 80 1 0157 Tilt limit mm in 1 7 0 07 Connecting rods Small end inside diameter mm in 15 985 15 998 0 6293 0 6298 Big end inside diameter mm in 36 000 36 024 1 4173 1 4183 Crankpin oil clearance mm in 0 020 ...

Page 23: ...earance mm in 0 03 0 08 0 0012 0 0031 Relief valve operating pressure kPa kgf cm2 psi 382 442 3 82 4 42 55 4 64 1 Thermostats Opening temperature C F 58 62 136 144 Fully open temperature C F 70 158 Valve open lower limit mm in 3 0 0 12 Fuel pump Discharge L US gal lmp gal hr 70 18 5 15 4 at 3 000 r min Pressure kPa kgf cm2 psi 49 0 49 7 1 Plunger stroke mm in 5 85 9 65 0 23 0 38 Carburetor Identif...

Page 24: ...timing cylinder 1 Degree Degree BTDC 8 5 at engine idle speed BTDC 30 at 6 000 r min Spark plug gap mm in 0 8 0 9 0 031 0 035 Ignition coil resistance Primary coil O B at 20 C 68 F Ω 0 08 0 11 Secondary coil spark plug wire spark plug wire at 20 C 68 F kΩ 3 4 4 7 CDI unit output peak voltage B W O at cranking loaded V 120 0 at 1 500 r min loaded V 120 0 at 3 500 r min loaded V 130 0 Pulser coil ou...

Page 25: ...d V 30 0 at 3 500 r min loaded V 80 0 Power bobbin resistance 1 Y B Y B at 20 C 68 F Ω 6 50 7 20 Lighting coil output peak voltage Y Y at cranking unloaded V 9 4 at 1 500 r min unloaded V 46 0 at 3 500 r min unloaded V 95 0 Lighting coil resistance 1 Y Y at 20 C 68 F Ω 0 90 1 10 Enrichment control system Prime Start Plunger extended length a 1 mm in 10 7 15 4 0 42 0 61 Prime Start resistance 2 Y Y...

Page 26: ...3 14 3 S 763 30 0 L 877 34 5 190 7 5 6 4 4 65 2 6 432 17 0 S 615 24 2 L 686 27 0 S 43 1 7 L 34 1 3 S 84 3 3 L 102 4 0 42 1 7 37 1 5 S 423 16 7 L 550 21 7 144 5 7 441 17 4 698 27 5 S 707 27 8 L 834 32 8 22 0 9 184 7 2 580 22 8 296 11 7 12 572 22 5 mm in 631 24 8 400 15 7 222 8 7 185 7 3 4 5 ...

Page 27: ...6D55F11 2 10 1 2 3 4 5 6 7 8 9 Clamp bracket Maintenance specification ...

Page 28: ...t nut M20 157 15 7 115 8 Stator coil bolt M5 6 0 6 4 4 Driven sprocket bolt M10 38 3 8 28 0 Pulser coil bolt M5 5 0 5 3 7 CDI unit bolt M6 5 0 5 3 7 CDI unit bracket bolt M6 5 0 5 3 7 Ignition coil bolt M6 8 0 8 5 9 Cylinder head bolt 1st M6 6 0 6 4 4 2nd 12 1 2 8 9 1st M9 23 2 3 17 0 2nd 46 4 6 34 0 Spark plug 17 1 7 12 5 Oil pump screw M6 4 0 4 3 0 Rocker arm locknut M6 14 1 4 10 3 Rocker arm sh...

Page 29: ...le grip screw M5 3 0 3 2 2 Shift rod lever bracket bolt M6 10 1 0 7 4 Spring hook bolt M6 10 1 0 7 4 Shift rod lever spring bolt M6 10 1 0 7 4 Retaining plate bolt M6 10 1 0 7 4 Upper mounting nut M8 24 2 4 17 7 Upper mount bolt M8 27 2 7 20 0 Mount housing nut M10 54 5 4 39 8 Steering friction bolt M8 4 0 4 3 0 Engine oil drain bolt M14 27 2 7 20 0 Upper case bolt M8 21 2 1 15 5 Exhaust manifold ...

Page 30: ...cable 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 Unless otherwise specified torque specifications require clean dry threads Components should be at room temperature Nut A Bolt B General torque specifications N m kgf m ft lb 8 mm M5 5 0 5 3 6 10 mm M6 8 0 8 5 8 12 mm M8 18 1 8 13 1...

Page 31: ...cooling water passage 3 7 Control system 3 7 Adjusting the throttle link 3 7 Adjusting the throttle cables tiller handle model 3 8 Adjusting the throttle cable remote control model 3 8 Checking the gear shift operation tiller handle model 3 9 Checking the gear shift operation remote control model 3 9 Checking the start in gear protection 3 9 Checking the engine idle speed 3 10 Checking the ignitio...

Page 32: ...CHK ADJ Periodic checks and adjustments 3 1 6D55F11 Special service tools 3 Oil filter wrench 90890 01426 Digital tachometer 90890 06760 Timing light 90890 03141 Leakage tester 90890 06840 ...

Page 33: ...ode external Check replace Anodes internal Check replace Cooling water passages Clean Top cowling Check Fuel filter can be disassembled Check replace Fuel system Check Fuel tank Yamaha portable tank Check clean Gear oil Change Lubrication points Lubricate Engine idle speed carburetor models Check adjust Propeller and cotter pin Check replace Shift link shift cable Check adjust Thermostat Check Thr...

Page 34: ...y repeat steps 2 4 6 Check the water separator drain holes for obstructions Clean if necessary Fuel system 3 Checking the fuel joint and fuel hoses fuel joint to carburetor 1 Check the fuel hose connections and fuel joints for leaks Replace if necessary Also check the fuel filter 1 fuel pump 2 and carburetor 3 for leaks or deterio ration Replace if necessary Checking the fuel filter 1 Check the fu...

Page 35: ...e engine oil 1 Start the engine warm it up and then turn it off 2 Remove the engine oil dipstick and oil filler cap 1 3 Place a drain pan under the drain hole and then remove the drain bolt 2 and let the oil drain completely NOTE Be sure to clean up any oil spills 4 Install the drain bolt and then tighten it to the specified torque 5 Pour the specified amount of the recom mended engine oil into th...

Page 36: ...nd then start the engine and warm it up for 5 minutes 7 Turn the engine off and then check the oil level and correct it if necessary Checking the timing belt 1 Remove the manual starter 2 While turning the flywheel magnet clock wise check the interior and the exterior of the timing belt for cracks damage or wear Replace if necessary 3 Turn the flywheel magnet clockwise to transfer the slack of the...

Page 37: ... and the gasket for damage Replace the spark plug if necessary 4 Check the spark plug gap a Adjust if out of specification 5 Install the spark plugs tighten them fin ger tight then to the specified torque using a spark plug wrench Checking the thermostat 1 Remove the cover 1 and thermostat 2 2 Suspend the thermostat in a container of water 3 Place a thermometer in the water and slowly heat the wat...

Page 38: ... cooling water passages inside the outboard motor Control system 3 Adjusting the throttle link NOTE For tiller handle models adjust the throttle link after adjusting the throttle cable 1 Loosen the screw 1 2 Turn the throttle cam 2 clockwise until it contacts the stopper 3 and then hold it in that position NOTE For remote control models the throttle cam cannot be turned unless the remote control l...

Page 39: ...tle cable 6 6 Tighten the locknut 7 Check the throttle grip for smooth opera tion and if necessary repeat steps 1 6 Adjusting the throttle cable remote control model 1 Loosen the locknut 1 remove the clip 2 and then disconnect the throttle cable joint 3 2 Contact the throttle cam 4 to the stopper 5 3 Adjust the position of the throttle cable joint until its hole is aligned with the set pin on the ...

Page 40: ...to the mating surfaces of the engine 3 Loosen the locknut 2 remove the clip 3 and then disconnect the shift cable joint 4 4 Adjust the position of the shift cable joint until its hole is aligned with the set pin on the shift link lever WARNING The shift cable joint must be screwed in a minimum of 8 0 mm 0 31 in a 5 Connect the cable joint install the clip and then tighten the locknut 6 Check the g...

Page 41: ...ngine idle speed Adjust if out of specifi cation 3 Turn the throttle stop screw 2 in direc tion a or b until the specified engine idle speed is obtained 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 Checking the ignition timing 1 Start the engine and warm it up for 5 min utes 2 Attach the special s...

Page 42: ... port it with the tilt stop lever 1 to check the lock mechanism of the lever Lower unit 3 Checking the gear oil level 1 Fully tilt the outboard motor down 2 Remove the check screw 1 and then check the gear oil level in the lower case NOTE If the oil is at the correct level the oil should overflow out of the check hole when the check screw is removed If necessary add sufficient gear oil of the reco...

Page 43: ...eakage 1 Remove the check screw 1 and then install the special service tool 2 Apply the specified pressure to check that the pressure is maintained in the lower unit for at least 10 seconds CAUTION Do not over pressurize the lower unit oth erwise the oil seals can be damaged NOTE Cover the check hole with a rag when remov ing the special service tool from the lower unit 3 If pressure drops below s...

Page 44: ...rease or paint the anodes otherwise they will be ineffective 2 Replace the anodes if excessively eroded Lubricating the outboard motor 1 Apply water resistant grease to the areas shown È Tiller handle model NOTE Apply grease to the grease nipples until it flows from the bushings a 2 Apply corrosion resistant grease to the area shown S6D53240 S6D53260 A A S6D53290 È ...

Page 45: ...g 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 4 7 Carburetor unit 4 8 Carburetor 4 9 Removing the carburetor 4 11 Checking the carburetor 4 11 Checking the Prime Start 4 12 Assembling the carburetor 4 12 Adjusting the throttle stop screw 4 13 ...

Page 46: ...FUEL Fuel system 4 1 6D55F11 Special service tools 4 Vacuum pressure pump gauge set 90890 06756 ...

Page 47: ...se routing 4 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 S6D54010 1 2 1 3 4 1 1 3 4 2 2 4 3 1 5 5 Special service tools Hose routing ...

Page 48: ...Q ty Remarks 1 Fuel joint 1 2 Bolt 1 M6 25 mm 3 Fuel hose 1 4 Bolt 1 M8 14 mm 5 Nut 1 6 Bracket 1 7 Fuel filter 1 8 Fuel filter element 1 9 O ring 1 Not reusable 10 Cup 1 11 Fuel hose 1 12 Fuel hose 1 13 Fuel pump 1 14 O ring 1 Not reusable 15 Bracket 1 16 Bolt 2 M6 30 mm ...

Page 49: ...name Q ty Remarks 1 Screw 4 ø5 43 mm 2 Cover 1 3 Gasket 1 Not reusable 4 Diaphragm 1 Not reusable 5 Fuel pump body 2 assembly 1 6 Nut 4 7 Pin 1 8 Plunger 1 9 Spring 1 10 Fuel pump body 1 1 11 Spring 1 12 Diaphragm 1 Fuel hoses and fuel filter Fuel pump ...

Page 50: ...ump outlet 6 Apply the specified positive pressure and check that there is no air leakage Disas semble the fuel pump if necessary NOTE Assemble the fuel pump valves to the fuel pump body and moisten the inside of the fuel pump with gasoline to ensure a good seal Disassembling the fuel pump 1 Disassemble the fuel pump as shown 2 Push down on the plunger and the dia phragm turn fuel pump body 1 1 ap...

Page 51: ...oline before assembly to obtain prompt operation of the fuel pump when starting the engine 1 Align the plunger and diaphragm installa tion holes a and then install the plunger into the diaphragm 2 Push down on the plunger and the dia phragm and then install the pin 1 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 o...

Page 52: ...ge 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 Replace the fuel hose connec tor of necessary Vacuum pressure pump gauge set 90890 06756 Fuel hose connector holding pressure 50 kPa 0 5 kgf cm2 7 3 psi ...

Page 53: ...emarks 1 Bolt 3 M6 25 mm 2 Fuel hose 1 3 Plastic tie 1 Not reusable 4 Blowby hose 1 5 Bolt 2 M6 100 mm 6 Intake silencer 1 7 Joint 1 8 Seal 1 9 O ring 1 Not reusable 10 Plate 1 11 Bracket 1 12 O ring 2 Not reusable 13 Spacer 1 14 Carburetor 1 Fuel pump Carburetor unit ...

Page 54: ...emarks 1 Throttle link rod 1 2 Screw 1 ø4 5 mm 3 Screw 1 ø4 10 mm 4 Retainer 1 5 Prime Start 1 6 O ring 1 Not reusable 7 Screw 3 ø4 10 mm 8 Cover 1 9 Gasket 1 Not reusable 10 Throttle stop screw 1 11 Spring 1 12 Pilot screw 1 13 O ring 1 Not reusable 14 Spring 1 ...

Page 55: ...uretor body 1 2 Float chamber 1 3 Gasket 1 Not reusable 4 Plunger rod 1 5 Plunger 1 6 Spring 1 7 Circlip 1 8 Ball 1 9 Drain screw 1 10 Screw 4 ø4 13 mm 11 Screw 1 ø4 7 mm 12 Float 1 13 Needle valve 1 14 Main jet 1 15 Main nozzle 1 16 Plug 1 17 Pilot jet 1 Carburetor ...

Page 56: ...necessary 2 Blow compressed air into all passages and jets 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 Do not use steel wire for cleaning the jets otherwise the jet diameters may be enlarged which may seriously affect performance 3 Check the main jet pilot jet and main nozzle for dirt or residue...

Page 57: ...cated in the following table Replace if out of specification 4 Measure the prime start resistance when the prime start plunger length is 10 7 mm 0 42 in Assembling the carburetor 1 Install the main nozzle 1 main jet 2 pilot jet 3 and plug 4 to the carburetor body as shown Float height a 8 7 9 7 mm 0 34 0 38 in Prime Start plunger extended length a reference data 10 7 15 4 mm 0 42 0 61 in Time min ...

Page 58: ... retor throttle lever 6 Turn the throttle cam 0 clockwise until it contacts the stopper A and then hold it in that position NOTE For remote control models the throttle cam cannot be turned unless the remote control lever is shifted to forward 7 Turn the throttle lever B clockwise so that the throttle valve is fully open 8 Tighten the screw C 9 Operate the throttle cam to check that the throttle va...

Page 59: ...14 1 2 3 4 5 6 7 8 9 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 Carburetor ...

Page 60: ...ng belt and sprockets 5 17 Installing the sprockets and timing belt 5 17 Removing the power unit 5 18 Cylinder head 5 20 Removing the cylinder head 5 23 Checking the valve springs 5 24 Checking the valves 5 24 Checking the valve guides 5 25 Replacing the valve guides 5 25 Checking the valve seat 5 26 Refacing the valve seat 5 26 Checking the rocker arms and rocker arm shaft 5 28 Checking the camsh...

Page 61: ...rance 5 39 Checking the piston pin boss bore 5 39 Checking the piston pin 5 39 Checking the connecting rod small end inside diameter 5 40 Checking the connecting rod big end side clearance 5 40 Checking the crankshaft 5 40 Checking the crankpin oil clearance 5 41 Selecting the connecting rod bearing 5 42 Checking the crankshaft main journal oil clearance 5 42 Selecting the crankshaft main bearing ...

Page 62: ...holder 90890 04086 Flywheel puller 90890 06521 Valve spring compressor 90890 04019 Valve spring compressor attachment 90890 06320 Valve guide remover installer 90890 06801 Valve guide reamer 90890 06804 Valve seat cutter holder 90890 06316 Valve seat cutter 90890 06312 90890 06315 90890 06323 90890 06325 90890 06327 90890 06328 ...

Page 63: ...6D55F11 5 2 1 2 3 4 5 6 7 8 9 Bearing outer race attachment 90890 06626 Driver rod LS 90890 06606 Oil filter wrench 90890 01426 Piston slider 90890 06529 Special service tools ...

Page 64: ...w specification and the compression pres sure for each cylinder is unbalanced add a small amount of engine oil to the cylin der and then check the pressure again NOTE If the compression pressure increases check the pistons and piston rings for wear Replace if necessary If the compression pressure does not increase check the valve clearance valve valve seat cylinder sleeve cylinder head gasket and ...

Page 65: ... b on the cyl inder head 5 Check the intake and exhaust valve clearances for cylinder 1 Adjust if out of specification 6 Turn the flywheel magnet clockwise and align the mark c on the driven sprocket with the mark b on the cyl inder head 7 Check the intake and exhaust valve clearances for cylinder 2 Adjust if out of specification NOTE Check the valve clearance when the engine is cold Note the meas...

Page 66: ...e adjusting screw in direction f To increase the valve clearance turn the adjusting screw in direction g 9 Tighten the rocker arm locknut to the specified torque and then check the valve clearance again Adjust if neces sary 10 Install the cylinder head cover fuel pump bolts spark plugs spark plug caps and manual starter T R Rocker arm locknut 4 14 N m 1 4 kgf m 10 3 ft lb S6D55100 5 4 g f ...

Page 67: ...t 1 M5 13 mm 2 Washer 1 3 Clip 2 4 Start in gear protection cable 1 5 Bolt 4 M6 25 mm 6 Manual starter 1 7 Bolt 1 M6 12 mm 8 Power unit 1 9 Dipstick 1 10 Dowel 2 11 Bolt 2 M6 14 mm 12 Gasket 1 Not reusable 13 Bolt 8 M8 80 mm 14 Apron 1 15 Bolt 2 M6 25 mm Power unit ...

Page 68: ...12 mm 2 Starter pulley 1 3 Nut 1 4 Washer 1 5 Flywheel magnet 1 6 Spacer 1 7 Bolt 3 M5 25 mm 8 Stator coil 1 9 Woodruff key 1 10 Woodruff key 1 11 Drive sprocket 1 12 Driven sprocket 1 13 Pulser coil 1 14 Bolt 2 M5 16 mm 15 Washer 1 16 Bolt 1 M10 40 mm 17 Timing belt 1 ...

Page 69: ...ainer 1 8 Bolt 1 M6 12 mm 9 Thermo sensor 1 10 Oil pressure switch 1 11 Cap 1 12 Oil pressure switch lead 1 13 Holder 1 14 Bolt 1 M6 16 mm 15 Bolt 1 16 Wiring harness 1 17 Bolt 3 M6 45 mm S6D55040 T R 5 N m 0 5 kgf m 3 7 ft Ib T R 5 N m 0 5 kgf m 3 7 ft Ib T R 8 N m 0 8 kgf m 5 9 ft Ib A 22 23 24 25 26 21 20 19 18 17 1 2 3 4 5 5 6 7 8 10 11 13 14 9 12 15 16 4 Power unit ...

Page 70: ... 1 20 Bolt 1 M5 16 mm 21 Holder 1 22 Bolt 3 M6 25 mm 23 Collar 3 24 Grommet 3 25 Bolt 1 M6 16 mm 26 Holder 1 S6D55040 T R 5 N m 0 5 kgf m 3 7 ft Ib T R 5 N m 0 5 kgf m 3 7 ft Ib T R 8 N m 0 8 kgf m 5 9 ft Ib A 22 23 24 25 26 21 20 19 18 17 1 2 3 4 5 5 6 7 8 10 11 13 14 9 12 15 16 4 ...

Page 71: ...Spacer 1 5 Throttle cam 1 6 Bolt 1 M6 10 mm 7 Bracket 1 8 Bolt 1 M6 25 mm Remote control model 9 Washer 1 Remote control model 10 Shift link lever 1 Remote control model 11 Collar 1 Remote control model 12 Shift link rod 1 Remote control model 13 Washer 1 Remote control model 14 Clip 1 Remote control model Power unit ...

Page 72: ...t 2 9 Starter rope guide 1 10 Damper 1 11 Manual starter handle 1 12 Cover 1 13 Oil pressure warning indicator 1 14 Bolt 2 M6 20 mm 15 Spring 2 16 Drive pawl 2 17 Circlip 2 S6D55020 A A 1 2 3 4 5 7 10 9 12 11 14 13 13 15 16 17 18 19 20 21 22 23 25 24 29 28 27 26 T R 8 N m 0 8 kgf m 5 9 ft Ib 8 6 30 T R 15 N m 1 5 kgf m 11 1 ft Ib T R 3 N m 0 3 kgf m 2 2 ft Ib A A ...

Page 73: ...23 Spring washer 1 24 Lock cam base plate 1 25 Spring 1 26 Bolt 3 M5 25 mm 27 Lock cam retainer 1 28 Lock cam 1 29 Spring 1 30 Cover 1 S6D55020 A A 1 2 3 4 5 7 10 9 12 11 14 13 13 15 16 17 18 19 20 21 22 23 25 24 29 28 27 26 T R 8 N m 0 8 kgf m 5 9 ft Ib 8 6 30 T R 15 N m 1 5 kgf m 11 1 ft Ib T R 3 N m 0 3 kgf m 2 2 ft Ib A A Power unit ...

Page 74: ... the length is out of specification Assembling the manual starter 1 Install the spring washer 1 and cartridge spring 2 into the manual starter case NOTE Install the spring washer with its projections a facing down towards the manual starter case Position the end b of the cartridge spring into the indentation c in the manual starter case 2 Install the sheave drum 3 into the man ual starter case NOT...

Page 75: ...e rope hole a and manual starter roller b are aligned Hold the sheave drum in this position NOTE If the sheave drum is turned less than 90 from where if stopped to where the rope hole and roller align turn it one full turn clockwise until the hole and roller align again 4 Pass the starter rope 2 through the rope hole in the sheave drum and out through the manual starter case 3 and then install the...

Page 76: ...ontacts the sheave drum 6 Pull the manual starter handle to extend the starter rope completely then mea sure the starter rope length Adjust if the starter rope length is out of specification Removing the timing belt and sprockets 1 Remove the manual starter 2 Turn the flywheel magnet clockwise and align the mark a on the driven sprocket with the mark b on the cyl inder head 3 Remove the starter pu...

Page 77: ... puller plate is par allel to the flywheel magnet NOTE Apply force to the crankshaft end until the fly wheel magnet comes off the tapered portion of the crankshaft 6 Disconnect the charge coil connectors and power bobbin connectors and remove the stator coil 2 7 Remove the timing belt 3 from the driven sprocket and then from the drive sprocket 8 Remove the drive sprocket 9 Remove the driven sprock...

Page 78: ...aligned with the mark d on the cylinder block Align if necessary 4 Install a new timing belt 3 to the drive sprocket and then to the driven sprocket with its part number in the upright posi tion CAUTION Do not to damage the timing belt during installation Do not twist turn inside out or bend the timing belt beyond the maximum limit of 25 mm 1 0 in otherwise it can be dam aged Do not get oil or gre...

Page 79: ...r pulley and then tighten the bolts to the specified torque 9 Install the manual starter Removing the power unit NOTE It is recommended to loosen the flywheel magnet nut before removing the power unit to improve working efficiency 1 Remove the manual starter 2 Disconnect the throttle cables tiller han dle model or throttle cable and shift cable remote control model 3 Remove the blowby hose and dip...

Page 80: ...POWR Power unit 5 19 6D55F11 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 ...

Page 81: ... 3 Dowel 2 4 Bolt 6 M9 95 mm 5 Bolt 3 M6 25 mm 6 O ring 1 Not reusable 7 O ring 1 Not reusable 8 O ring 1 Not reusable 9 Oil pump assembly 1 10 Bolt 4 M6 35 mm 11 Gasket 1 Not reusable 12 Bolt 5 M6 20 mm 13 Cylinder head cover 1 14 O ring 1 15 Oil filler cap 1 16 Bolt 2 M6 20 mm 17 Plate 2 Power unit Cylinder head ...

Page 82: ...POWR Power unit 5 21 6D55F11 5 No Part name Q ty Remarks 18 Cover 2 19 Bolt 2 M5 12 mm 20 Anode 2 21 Grommet 2 22 Spark plug 2 ...

Page 83: ...t 4 4 Valve seal 4 Not reusable 5 Valve spring 4 6 Valve spring retainer 4 7 Valve cotter 8 8 Rocker arm assembly 4 9 Rocker arm retainer 2 10 Bolt 3 M8 30 mm 11 Stopper guide 1 12 Tensioner 1 13 Rocker arm shaft 1 14 Retaining bolt 1 15 Gasket 1 Not reusable 16 Camshaft 1 17 Oil seal 1 Not reusable Cylinder head ...

Page 84: ...linder head and cylinder block 3 Remove the oil pump assembly 1 4 Remove the rocker arm assembly 2 and rocker arm shaft 3 5 Remove the retaining bolt 4 then the camshaft 5 6 Remove the intake and exhaust valves NOTE Be sure to keep the valves springs and other parts in the order as they were removed S6D55450 S6D55470 3 2 Valve spring compressor 6 90890 04019 Valve spring compressor attachment 7 90...

Page 85: ... margin thickness a Replace if below specification 3 Measure the valve stem diameter b Replace if out of specification 4 Measure the valve stem runout Replace if above specification Valve spring free length a 39 85 mm 1 5689 in Valve spring tilt limit b 1 7 mm 0 07 in Valve margin thickness a Intake 0 8 mm 0 0315 in Exhaust 0 9 mm 0 0354 in Valve stem diameter b Intake 5 475 5 490 mm 0 2156 0 2161...

Page 86: ...ce tool from the cam shaft side until the valve guide clip 3 contacts the cylinder head NOTE Apply engine oil to the surface of the new valve guide 3 Insert the special service tool into the valve guide 2 and then ream the valve guide NOTE Turn the valve guide reamer clockwise to ream the valve guide Do not turn the reamer counterclockwise when removing the reamer Valve guide inside diameter a Int...

Page 87: ...e face Reface the valve seat if the valve is not seated properly or if the valve seat contact width is out of specification Replace the valve guide if the valve seat contact is uneven Refacing the valve seat 1 Reface the valve seat with the valve seat cutters Valve guide inside diameter Intake and exhaust 5 500 5 512 mm 0 2165 0 2170 in Valve seat contact width a Intake and exhaust 0 9 1 1 mm 0 03...

Page 88: ...top edge of the valve seat b Previous contact width 4 Use a 60 cutter to adjust the contact width of the bottom edge of the valve seat b Previous contact width 5 Use a 45 cutter to adjust the contact width of the valve seat to specification b Previous contact width c Specified contact width 6 If the valve seat contact area is too wide and situated in the center of the valve face use a 30 cutter to...

Page 89: ...om pound onto the valve seat and then lap the valve using a valve lapper commer cially available CAUTION Do not get the lapping compound on the valve stem and valve guide 10 After every lapping procedure be sure to clean off any remaining lapping com pound from the cylinder head and the valve 11 Check the valve seat contact area of the valve again Checking the rocker arms and rocker arm shaft 1 Ch...

Page 90: ...hecking the cylinder head 1 Eliminate carbon deposits from the com bustion chambers and check for deterio ration 2 Check the cylinder head warpage using a straightedge 1 and thickness gauge 2 in six directions as shown Replace if above specification Cam lobe a Intake and exhaust 30 834 31 034 mm 1 2139 1 2218 in Cam lobe b Intake and exhaust 25 90 26 10 mm 1 0197 1 0276 in Camshaft runout limit 0 ...

Page 91: ... if out of specification Installing the valves 1 Install a new valve seal 1 into the valve guide Cylinder head warpage limit 0 10 mm 0 0039 in S6D55560 2 1 S6D55570 Clearance a 0 09 0 15 mm 0 0035 0 0059 in Clearance b Within 0 12 mm 0 047 in Clearance c 0 03 0 08 mm 0 0012 0 0031 in S62Y5590 E 1 Cylinder head ...

Page 92: ... install the valve cotter 8 using a thin screwdriver with a small amount of grease applied to it 4 Lightly tap the valve spring retainer with a plastic hammer to set the valve cotter securely Installing the camshaft 1 Install a new oil seal 1 2 Install the camshaft 4 in the direction shown then the retaining bolt 5 Valve spring compressor 6 90890 04019 Valve spring compressor attachment 7 90890 06...

Page 93: ...on the tensioner and stopper guide are facing up 2 Install the rocker arm shaft assembly to the cylinder head by installing the bolts and then tighten them to the specified torque Installing the oil pump 1 Install the oil pump 1 by aligning the oil pump drive shaft a with the camshaft pin b NOTE Before installing the oil pump be sure to fill it with a small amount of engine oil through the oil pas...

Page 94: ...ion bolt 1 3 Exhaust cover 1 4 Holder 2 5 Bolt 9 M6 35 mm 6 Thermostat cover 1 7 Gasket 1 Not reusable 8 Thermostat 1 9 Gasket 1 Not reusable 10 Bolt 1 M8 35 mm 11 Engine hanger 1 12 Filter 1 Steel 13 Gasket 1 Not reusable 14 Plug 1 Steel 15 Gasket 1 Not reusable 16 Cover 1 17 Bolt 4 M6 20 mm ...

Page 95: ...er 1 4 O ring 1 Not reusable 5 Bolt 4 M6 20 mm 6 Bolt 6 M8 82 mm 7 Bolt 6 M6 35 mm 8 Crankcase 1 9 Main bearing 6 10 Bolt 4 11 Connecting rod assembly 2 12 Connecting rod bearing 4 13 Oil seal 1 Not reusable 14 Balancer rod 1 15 Crankshaft 1 16 Oil seal 1 Not reusable 17 Dowel 2 Cylinder block ...

Page 96: ...POWR Power unit 5 35 6D55F11 5 No Part name Q ty Remarks 18 Cylinder block 1 19 Piston ring assembly 2 20 Piston 2 21 Piston pin 2 22 Clip 4 Not reusable ...

Page 97: ...r NOTE Be sure to clean up any oil spills 3 Remove the cover 1 4 Remove the nut 2 then the balancer piston 3 5 Remove the crankcase bolts in the sequence shown 6 Remove the connecting rod bolts and the connecting rod caps and then remove the connecting rod and piston assem blies 7 Remove the crankshaft and oil seals Oil filter wrench 90890 01426 S6D55730 S6D55760 Cylinder block ...

Page 98: ... specification Checking the cylinder bore 1 Measure the cylinder bore D1 D6 at measuring points a b and c and in direction d D1 D3 D5 which is parallel to the crankshaft and direction e D2 D4 D6 which is at a right angle to the crankshaft a 20 mm 0 8 in b 40 mm 1 6 in c 60 mm 2 4 in 2 Calculate the taper limit Replace the cyl inder block if above specification 3 Calculate the out of round limit Re...

Page 99: ...g point Replace if out of specification Out of round limit D2 D1 measuring point a D6 D5 measuring point c 0 05 mm 0 0020 in Piston clearance 0 035 0 065 mm 0 0014 0 0026 in Piston ring dimensions Top ring a B 1 17 1 19 mm 0 0461 0 0469 in T 2 25 2 45 mm 0 0885 0 0965 in 2nd ring b B 1 47 1 49 mm 0 0579 0 0587 in T 2 60 2 80 mm 0 1024 0 1102 in Oil ring c B 2 36 2 48 mm 0 0929 0 0976 in T 2 75 mm ...

Page 100: ...in boss bore Replace the piston if out of specification Checking the piston pin 1 Measure the piston pin diameter Replace if out of specification Piston ring groove Top ring a 1 21 1 23 mm 0 0476 0 0484 in 2nd ring b 1 51 1 53 mm 0 0594 0 0602 in Oil ring c 2 52 2 54 mm 0 0992 0 1000 in Piston ring side clearance Top ring a 0 02 0 06 mm 0 0008 0 0024 in 2nd ring b 0 02 0 06 mm 0 0008 0 0024 in Oil...

Page 101: ...rankshaft journal diameter a crankpin diameter b and crankpin width c Replace the crankshaft if out of specification 2 Measure the crankshaft runout Replace the crankshaft if above specification Connecting rod small end inside diameter a 15 985 15 998 mm 0 6293 0 6298 in Connecting rod big end side clearance a 0 05 0 22 mm 0 0020 0 0087 in S6D55800 a a Crankshaft journal diameter a 42 984 43 000 m...

Page 102: ...t a piece of Plastigauge PG 1 onto the crankpin parallel to the crankshaft NOTE Be sure not to put the Plastigauge PG 1 over the oil hole in the crankpin of the crank shaft 4 Install the connecting rod to the crankpin 3 NOTE Make sure that the marks b of the connect ing rod faces towards the flywheel magnet side of the crankshaft 5 Tighten the connecting rod bolts to the specified torques in two s...

Page 103: ...or the con necting rod bearing from the table Checking the crankshaft main journal oil clearance 1 Clean the bearings main journals and bearing portions of the crankcase and cylinder block 2 Place the cylinder block upside down on a bench 3 Install half of the bearings 1 and the crankshaft 2 into the cylinder block 3 NOTE Install the main bearings in their original positions Insert the projection ...

Page 104: ...o the specified torques in two stages 8 Remove the crankcase and then mea sure the width of the compressed Plasti gauge PG 1 on each main journal Replace the main bearing if out of speci fication Selecting the crankshaft main bearing 1 When replacing the main bearing select the suitable bearing as follows 2 Check the cylinder block mark a on the cylinder block 3 Select the suitable color b for the...

Page 105: ...ing 7 onto each piston with the T marks d of the second ring and the top ring facing upward 3 Offset the piston ring end gaps as shown CAUTION Do not scratch the pistons or break the piston rings NOTE After installing the piston rings check that they move smoothly 4 Install the upper bearing into the con necting rod and the lower bearing into the connecting rod cap 8 NOTE Install the connecting ro...

Page 106: ...stall the balancer rod onto the crank shaft 8 Set the crankshaft A and oil seals B and C into the cylinder block as shown NOTE Apply engine oil to the inner oil seals before installation 9 Install the connecting rod caps D to the connecting rods and then tighten the connecting rod bolts to the specified torques in two stages NOTE Align the alignment marks g on the con necting rod cap and connectin...

Page 107: ...ly engine oil to the crankcase bolts before installation 14 Install the balancer piston E into the crankcase and then tighten the balancer piston nut F to the specified torque 15 Install a new O ring and the balancer cover G and then tighten the bolts H to the specified torque NOTE Apply engine oil to the balancer piston nut and balancer cover bolts before installation S6D55970 E T R 1 6 Crankcase...

Page 108: ...ied torques in two stages and in the sequence shown Installing the cylinder head 1 Install a new gasket and the cylinder head and then tighten the bolts to the specified torques in the sequence shown CAUTION Do not reuse the cylinder head gasket always replace it with a new one NOTE Apply engine oil to the cylinder head bolts before installation Tighten the bolts to the specified torques in two st...

Page 109: ...Install the timing belt 3 to the drive sprocket and then to the driven sprocket with its part number in the upright posi tion CAUTION Do not to damage the timing belt during installation NOTE When installing the timing belt lift the drive sprocket slightly to ease installation Be care ful the Woodruff key for the drive sprocket does not slide out of position T R Cylinder head bolt M9 1st 23 N m 2 ...

Page 110: ...ecified torque 4 Connect the engine stop lanyard switch leads cooling water pilot hose and fuel hose 5 Install the dipstick 6 Connect the blowby hose 7 7 Connect the throttle cable 8 and shift cable 9 remote control model or throt tle cables 0 tiller handle model and then adjust their lengths For adjustment procedures see Chapter 3 8 Install the stator coil 9 Install the Woodruff key Valve clearan...

Page 111: ... Apply engine oil to the flywheel magnet nut before installation 11 Install the starter pulley and then tighten the bolts to the specified torque 12 Install all parts removed during disas sembly Flywheel holder 90890 06522 T R Flywheel magnet nut 157 N m 15 7 kgf m 115 8 ft lb Universal clutch holder 90890 04086 T R Starter pulley bolt 25 N m 2 5 kgf m 18 4 ft lb Cylinder block ...

Page 112: ...POWR Power unit 5 51 6D55F11 MEMO ...

Page 113: ...ng the oil seal housing 6 14 Drive shaft and lower case 6 15 Removing the drive shaft 6 16 Disassembling the drive shaft 6 16 Disassembling the forward gear 6 16 Disassembling the lower case 6 16 Checking the pinion and forward gear 6 17 Checking the bearings 6 17 Checking the drive shaft 6 17 Checking the lower case 6 17 Assembling the lower case 6 17 Assembling the forward gear 6 18 Assembling t...

Page 114: ...ide plate 90890 06501 Center bolt 90890 06504 Bearing separator 90890 06534 Stopper guide stand 90890 06538 Bearing puller assembly 90890 06535 Needle bearing attachment 90890 06608 90890 06611 90890 06615 Driver rod L3 90890 06652 Ball bearing attachment 90890 06635 90890 06637 Driver rod LS 90890 06606 ...

Page 115: ... attachment 90890 06640 90890 06643 90890 06644 Drive shaft holder 3 90890 06517 Driver rod SL 90890 06602 Bearing outer race attachment 90890 06625 90890 06628 Driver rod LL 90890 06605 Pinion height gauge 90890 06710 Pinion height gauge plate B 90890 06712 Digital caliper 90890 06704 Special service tools ...

Page 116: ...LOWR Lower unit 6 3 6D55F11 Shimming plate 90890 06701 Backlash indicator 90890 06706 Magnet base plate 90890 07003 Dial gauge set 90890 01252 Magnet base B 90890 06844 ...

Page 117: ...k screw 1 3 Gasket 2 Not reusable 4 Drain screw 1 5 Adjusting nut 1 6 Locknut 1 7 Cooling water inlet cover 2 8 Nut 2 9 Bolt 1 M6 35 mm 10 Washer 1 11 Anode 1 12 Screw 2 ø5 26 mm 13 Bolt 4 M10 35 mm 14 Bolt 1 M6 20 mm 15 Trim tab 1 16 Spacer 1 17 Propeller 1 Special service tools Lower unit ...

Page 118: ...LOWR Lower unit 6 5 6D55F11 6 No Part name Q ty Remarks 18 Collar 1 19 Washer 1 20 Nut 1 21 Cotter pin 1 Not reusable 22 Dowel 2 ...

Page 119: ...L transom model 3 O ring 1 Not reusable S transom model 4 Water tube 1 S transom model 5 O ring 1 Not reusable S transom model 6 Bolt 4 M6 40 mm 7 Extension plate 1 8 Cover 1 9 Water pump housing 1 10 Insert cartridge 1 11 O ring 1 Not reusable 12 Impeller 1 13 Outer plate cartridge 1 14 Woodruff key 1 Lower unit ...

Page 120: ...opeller with your hands when loosening or tightening it Be sure to remove the clip from the engine stop lanyard switch Put a block of wood between the anti cavitation plate and propeller to keep the propeller from turning 3 Remove the anode 1 and trim tab 2 NOTE Note the trim tab position 4 Loosen the locknut 3 and then remove the adjusting nut 4 5 Loosen the bolts 5 and then remove the lower unit...

Page 121: ...k 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 Replace if necessary S6D56050 a 1 Lower unit ...

Page 122: ...tch 1 3 Cross pin 1 4 Spring 1 5 Spring 1 6 Propeller shaft 1 7 Washer 1 8 Reverse gear 1 9 Reverse gear shim 10 O ring 1 Not reusable 11 Ball bearing 1 Not reusable 12 O ring 2 Not reusable 13 Propeller shaft housing 1 14 Needle bearing 1 15 Oil seal 2 Not reusable 16 Oil seal 2 Not reusable 17 Water seal 1 ...

Page 123: ...5 6 7 8 9 6 No Part name Q ty Remarks 18 Bolt 2 M6 25 mm 19 Shift rod bracket 1 20 Shift rod plate 1 21 O ring 1 Not reusable 22 Oil seal housing 1 23 Dowel 3 24 Gasket 1 Not reusable 25 Shift rod 1 Propeller shaft housing ...

Page 124: ...ve the reverse gear and reverse gear shim s 2 Remove the ball bearing CAUTION Do not reuse the bearing always replace it with a new one 3 Remove the oil seals and needle bear ing Bearing housing puller claw S 1 90890 06564 Stopper guide plate 2 90890 06501 Center bolt 3 90890 06504 Bearing separator 1 90890 06534 Stopper guide plate 2 90890 06501 Stopper guide stand 3 90890 06538 Bearing puller as...

Page 125: ...he propeller shaft and shift rod 1 Check the shift rod cracks or wear Replace if necessary 2 Check the propeller shaft for bends or wear Replace if necessary 3 Measure the propeller shaft runout 4 Check the dog clutch and shift plunger for cracks or wear Replace if necessary Assembling the propeller shaft assembly 1 Install the dog clutch as shown NOTE Install the dog clutch 1 with the F mark a fa...

Page 126: ...ousing then the other oil seal 3 Install the original shim s 6 and new ball bearing 7 onto the reverse gear 8 using a press CAUTION Add or remove shim s if necessary if replacing the reverse gear ball bearing propeller shaft housing or lower case NOTE Install the ball bearing with the manufacturer identification mark f facing inward reverse gear side 4 Install the reverse gear assembly into the pr...

Page 127: ... Apply grease to new oil seals and then install them into the oil seal housing to the specified depth Needle bearing attachment 0 90890 06608 Ball bearing attachment 1 90890 06635 Driver rod LS 2 90890 06606 Depth a 5 5 6 0 mm 0 217 0 236 in Propeller shaft housing ...

Page 128: ...e 6 No Part name Q ty Remarks 1 Drive shaft 1 2 Taper roller bearing assembly 1 Not reusable 3 Pinion shim 4 Sleeve 1 5 Needle bearing 1 6 Pinion 1 7 Nut 1 8 Forward gear shim 9 Taper roller bearing assembly 1 Not reusable 10 Forward gear 1 11 Lower case 1 ...

Page 129: ... bearing always replace it with a new one Disassembling the forward gear 1 Remove the taper roller bearing from the forward gear using a press CAUTION Do not reuse the bearing always replace it with a new one Disassembling the lower case 1 Remove the taper roller bearing outer race and shim s NOTE Install the claws as shown Drive shaft holder 3 1 90890 06517 Bearing inner race attachment 3 90890 0...

Page 130: ...hecking the lower case 1 Check the skeg and torpedo for cracks or damage Replace the lower case if nec essary Assembling the lower case 1 Install the needle bearing into the lower case to the specified depth NOTE Install the needle bearing with the manufac ture identification mark a facing up When using the driver rod do not strike the special service tool in a manner that will force the stopper b...

Page 131: ...race CAUTION Add or remove shim s if necessary if replacing the forward gear or lower case Assembling the forward gear 1 Install a new taper roller bearing into the forward gear using a press Assembling the drive shaft 1 Install a new drive shaft bearing onto the drive shaft using a press Depth c 185 186 mm 7 283 7 323 in Bearing outer race attachment 4 90890 06628 Driver rod LS 5 90890 06606 Bear...

Page 132: ...ase and then tighten the bolts 5 to the specified torque Installing the water pump and shift rod 1 Install the shift rod 1 new gasket 2 and oil seal housing 3 2 Install the shift rod plate 4 and shift rod bracket 5 and then tighten the bolts 6 3 Install the outer plate cartridge and then install the woodruff key into the drive shaft 4 Align the groove in the impeller 7 with the Woodruff key 8 and ...

Page 133: ...he pump housing assembly B into the lower case and then install the cover C 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 Align the cover projection c with the hole d in the pump housing 7 Install the extension plate D and then tighten the bolts E È S transom model É L transom model S6D562...

Page 134: ... Turn the adjusting nut 3 to the specified length a and then tighten the locknut 4 5 Install the trim tab 5 to its original posi tion and then tighten the trim tab bolt 6 6 Install the propeller and propeller nut and then tighten the nut finger tight Place a block of wood between the anti cavitation plate and propeller to keep the propeller from turning and then tighten the nut to the specified to...

Page 135: ...grooves in the propeller nut 7 do not align with the cotter pin hole tighten the nut until they are aligned 7 Insert a gear oil tube or gear oil pump into the drain hole and slowly fill the gear oil until oil flows out of the check hole and no air bubbles are visible 8 Install the check screw and quickly install the drain screw T R Propeller nut 7 34 N m 3 4 kgf m 25 1 ft lb Recommended gear oil H...

Page 136: ...LOWR Lower unit 6 23 6D55F11 Shimming 6 S6D56370 T3 A3 B3 42 5 T1 T2 24 0 24 0 B2 A1 A2 B1 ...

Page 137: ...ness T3 by using the specified measurement s and the calcula tion formula Install the special service tool onto the drive shaft so that the shaft is at the center of the hole Tighten the wing nuts another 1 4 of a turn after they contact the plate 2 2 Install the pinion and pinion nut and then tighten the nut to the specified torque 3 Measure the distance M3 between the special service tool and th...

Page 138: ...and 1 1 mm Selecting the forward gear shims 1 Turn the taper roller bearing outer race 1 two or three times to seat the rollers and then measure the bearing height M1 as shown NOTE Select the shim thickness T1 by using the specified measurement s and the calcula tion formula Measure the bearing outer race at three points to find the height average 2 Calculate the forward gear shim thick ness T1 as...

Page 139: ...f T1 is 1 30 mm then the forward gear shim is 1 2 mm Selecting the reverse gear shims 1 Install the ball bearing onto the propeller shaft housing 2 Measure the bearing housing height M2 as shown NOTE Select the shim thickness T2 by using the specified measurement s and the calcula tion formula Measure the bearing housing at three points to find the height average Calculation formula Forward gear s...

Page 140: ...1 1 mm Backlash 6 Measuring the forward and reverse gear backlash 1 Remove the water pump assembly 2 Set the gear shift to the neutral position at the lower unit 3 Install the special service tools so that it pushes against the propeller shaft NOTE Tighten the center bolt while turning the drive shaft until the drive shaft can no longer be turned 4 Install the backlash indicator onto the drive sha...

Page 141: ...s shown NOTE Tighten the propeller nut B while turning the drive shaft until the drive shaft can no longer be turned 9 Slowly turn the drive shaft clockwise and counterclockwise and measure the back lash when the drive shaft stops in each direction Backlash indicator 4 90890 06706 Magnet base plate 5 90890 07003 Dial gauge set 6 90890 01252 Magnet base B 7 90890 06844 Forward gear backlash 0 30 0 ...

Page 142: ...ement 11 Remove the special service tools and then install the water pump assembly Reverse gear backlash Shim thickness Less than 0 92 mm 0 0362 in To be decreased by 1 29 M 0 49 More than 1 65 mm 0 0650 in To be increased by M 1 29 0 49 Available shim thicknesses 1 0 1 1 1 2 and 1 3 mm ...

Page 143: ...mbling 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 7 11 Installing the steering arm 7 12 Installing the upper case 7 12 Clamp brackets swivel bracket 7 13 Removing the clamp brackets 7 16 Disassembling the swivel bracket 7 16 Assembling the swivel bracket 7 16 Installing the clamp brackets 7 17 ...

Page 144: ...1 Throttle cable 2 2 Engine stop lanyard switch 1 3 Nut 1 4 Grommet 1 5 Shift link rod 1 6 Shift lever 1 7 Washer 1 8 Wave washer 1 9 Collar 1 10 Nut 1 11 Bolt 1 M6 30 mm 12 Self locking nut 1 13 Nut 1 14 Cable guide 1 15 Bushing 1 16 Steering bracket 1 17 Plastic washer 1 ...

Page 145: ... Wave washer 2 20 Bushing 1 21 Tiller handle bracket 1 22 Throttle friction adjuster 1 23 Throttle grip 1 24 Screw 1 ø5 25 mm 25 Washer 1 26 Spring 1 27 Bushing 1 28 Throttle shaft 1 29 Friction piece 1 30 Bolt 2 M6 20 mm 31 Plate 1 32 Nut 2 33 Engine stop lanyard 1 Tiller handle ...

Page 146: ... the tiller handle bracket to the steering bracket 6 tighten the tiller han dle bracket nut 7 to the specified torque and then tighten the self locking nut 8 to the specified torque NOTE Route the engine stop lanyard switch lead 9 and throttle cables 0 and A as shown Install the corrugated tubes B so that they contact the tiller handle bracket C T R Engine stop lanyard switch nut 2 N m 0 2 kgf m 1...

Page 147: ...art in gear protection lever 1 5 Shift rod lever 1 6 Shift rod 1 7 Bottom cowling 1 8 Rubber seal 1 9 Grommet 6 10 Grommet 1 Remote control model 11 Grommet 1 Remote control model 12 Grommet 1 Tiller handle model 13 Socket cord assembly 1 Remote control model 14 Cable holder 1 15 Bolt 1 M6 20 mm 16 Spring 1 17 Bolt 4 M6 30 mm Tiller handle Bottom cowling ...

Page 148: ...Water outlet 1 21 Bolt 1 22 Hook 1 23 Bolt 1 M6 20 mm 24 Lever 1 25 Bushing 1 26 Bushing 1 27 Wave washer 1 28 Washer 1 29 Cowling lock lever 1 30 Grommet 1 Tiller handle model 31 Grommet 1 Remote control model 32 Cable guide 1 Remote control model 33 Bolt 2 M6 30 mm 34 Retaining plate 1 ...

Page 149: ... Rubber damper 2 3 Rubber damper 1 4 Bolt 2 M10 80 mm 5 Bolt 2 M10 120 mm 6 Nut 4 7 Screw 1 ø6 8 mm 8 Ground lead 1 9 Grease nipple 1 10 Bolt 3 M8 30 mm 11 Upper mount 1 12 Plate 1 13 Bolt 2 M8 185 mm 14 Upper case assembly 1 15 Nut 2 16 Steering arm 1 17 Washer 1 Bottom cowling Upper case steering arm ...

Page 150: ...t name Q ty Remarks 18 Bushing 1 19 Straight key 1 20 Bushing 1 21 O ring 1 Not reusable 22 Bushing 1 23 Nut 2 Remote control model 24 Washer 2 Remote control model 25 Steering hook 1 Remote control model 26 Bolt 1 M8 20 mm 27 Rubber seal 1 ...

Page 151: ... ø5 15 mm 3 Baffle plate 1 4 Dowel 2 5 Bolt 4 M8 30 mm 6 Gasket 1 7 Bolt 3 M6 50 mm 8 Washer 3 9 Bracket 1 10 Exhaust manifold 1 11 Gasket 1 Not reusable 12 Oil pan 1 13 Gasket 1 Not reusable 14 Drain bolt 1 M14 12 mm 15 Damper 1 16 Dowel 2 17 Bolt 10 M6 25 mm Upper case steering arm ...

Page 152: ...haust guide 1 20 Oil seal 1 Not reusable 21 Grommet 1 22 Anode 1 23 Cover 1 24 Bolt 1 M5 12 mm 25 Cover 1 26 Bolt 1 M6 20 mm 27 Cooling water pipe 1 28 Rubber seal 1 29 Bolt 2 M6 16 mm 30 Oil strainer 1 31 Bolt 3 M6 25 mm 32 Gasket 1 Not reusable 33 Relief valve housing 1 34 Relief valve 1 ...

Page 153: ...3 Remove the oil strainer 3 and relief valve assembly 4 from the exhaust guide 2 Checking the oil strainer 1 Check the oil strainer for dirt and residue Clean if necessary Checking the oil pan 1 Check the exhaust guide and exhaust manifold for damage or corrosion Replace if necessary 2 Check the cooling water pipe for defor mation or corrosion Replace if neces sary 3 Check the relief valve for clo...

Page 154: ...gasket and the engine oil drain bolt and then tighten the bolt to the specified torque 10 Install the upper case bolts 0 and then tighten them to the specified torque 11 Install the upper mount A and bolts B into the upper case and then tighten the bolts to the specified torque Removing the steering arm 1 Remove the steering arm from the swivel bracket by pulling the arm off the bracket T R Exhaus...

Page 155: ... upper mounting bolts into the swivel bracket 1 2 Install the upper mounting nuts 2 and then tighten them to the specified torque 3 Install the lower mount housing 3 lower mounting bolts 4 lower mounting nuts 5 lower mounting bolts 6 and lower mounting nuts 7 and then tighten the nuts finger tight 4 Tighten the lower mounting nuts 5 to the specified torque then tighten the lower mounting nuts 7 to...

Page 156: ... No Part name Q ty Remarks 1 Tilt pin 1 2 Spring 1 3 Bolt 1 M8 255 mm 4 Collar 1 5 Washer 1 6 Nut 1 7 Cap nut 2 8 Self locking nut 2 9 Plate 1 10 Through tube 1 11 Clamp bracket 1 12 Washer 2 13 Bushing 2 14 Swivel bracket 1 15 Clamp bracket 1 16 Nut 2 17 Washer 2 ...

Page 157: ...6 7 8 9 7 No Part name Q ty Remarks 18 Plastic washer 2 19 Tilt stopper plate 2 20 Wave washer 2 21 Bolt 2 22 Pin 1 23 Bushing 2 24 Pin 1 25 Circlip 2 26 Collar 1 27 Bushing 1 28 Grease nipple 3 Clamp brackets swivel bracket ...

Page 158: ...Remarks 1 Spring 1 2 Tilt lock rod 1 3 Tilt lever 1 4 Screw 1 ø5 5 mm 5 Collar 1 6 Circlip 1 7 Tilt lock lever 1 8 Bushing 1 9 Pin 1 10 Bushing 1 11 Tilt support bar 1 12 Spring 2 13 Pin 1 1 14 Pin 2 1 15 Tilt lock plate 2 16 Tilt lock arm 1 17 Collar 1 ...

Page 159: ...pin and tilt support bar 2 Remove the bushings and collar 3 Remove the pin 1 pin 2 collar tilt lock plates tilt lock arm and springs Assembling the swivel bracket 1 Install the tilt lock arm 1 tilt lock plates 2 pin 2 3 pin 1 4 collar 5 springs 6 to the swivel bracket 7 2 Install the bushings 8 and 9 and collar 0 to the swivel bracket 3 Install the tilt support bar A and pin B and then insert the ...

Page 160: ...elf locking nuts 1 to the specified torque and then tighten the cap nuts 4 Install the tilt stopper plate bolts and tilt stopper plate nuts and then tighten the nuts to the specified torque 5 Install the collar 2 and clamp bracket bolt 3 and then tighten the clamp bracket nut 4 to the specified torque 6 Apply water resistant grease to the grease nipples NOTE Apply the grease until it comes out of ...

Page 161: ...rboard 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 Checking the CDI unit 8 8 Checking the pulser coil 8 8 Checking the charge coil 8 9 Checking the power bobbin 8 9 Checking the lighting coil 8 9 Checking the engine stop lanyard switch 8 10 Checking the thermo sensor 8 10 Checking the oil pressure switch 8 10 Chec...

Page 162: ... 6D55F11 Special service tools 8 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 ...

Page 163: ...touch any of the connections of the digital tester leads NOTE Use the peak voltage adapter with the digi tal circuit tester When measuring the peak voltage set the selector on the digital circuit tester to the DC voltage mode Connect the positive pin on the peak volt age adapter to the positive terminal of the digital circuit tester Measuring the lower resistance When measuring a resistance of 10 ...

Page 164: ...ELEC Electrical systems 8 3 6D55F11 Electrical components 8 Front and aft views 1 CDI unit 2 Ignition coil 3 Engine stop lanyard switch coupler remote control model ...

Page 165: ...6D55F11 8 4 1 2 3 4 5 6 7 8 9 Port and starboard views 1 Oil pressure switch 2 Thermo sensor 3 Pulser coil 4 Spark plugs 5 Prime Start Electrical components ...

Page 166: ...il 5 Thermo sensor 6 Ignition coil 7 Wiring harness 8 Prime Start 9 Engine stop lanyard switch 0 Oil pressure warning indicator Color code B Black O Orange P Pink R Red W White Y Yellow B W Black white Br B Brown black G W Green white P W Pink white R W Red white W G White green Y B Yellow black Y R Yellow red ...

Page 167: ... Y Y B Y B Y Y W W Y B P W R O O Br B Y R Y R P P W Y B B W P W G W W G Y B R W Br B Br B Br B B W Y Y O G W Y R B W G Y Y P R W Br B C B A A B C R W Y R W G B W O B P W Br B P Y Y G W R W R W B Y B G W W G Y B S6D5WD01 7 F25CMH F25CM Electrical components ...

Page 168: ...out of the removed spark plug caps Keep flammable gas or liquids away since this test can produce sparks Checking the spark plug caps 1 Remove the spark plug caps from the spark plug wires by turning the caps counterclockwise 2 Measure the spark plug cap resistance Replace if out of specification Checking the ignition coil 1 Remove the spark plug caps from the spark plug wires by turning the caps ...

Page 169: ... 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 Digital circuit tester 90890 03174 Peak voltage adapter B 90890 03172 CDI unit output peak voltage Black white B W Orange O r min Loaded Cranking 1 500 3 500 DC V 120 120 130 Digital circuit tester 90890 03174 Peak voltage adapter B 90890 03172 Test harness...

Page 170: ...n white G W White green W G r min Unloaded Loaded Cranking 1 500 3 500 DC V 170 130 140 140 Charge coil resistance reference data Green white G W White green W G 660 710 Ω at 20 C 68 F Digital circuit tester 90890 03174 Peak voltage adapter B 90890 03172 Power bobbin output peak voltage Yellow black Y B Yellow black Y B r min Unloaded Cranking 1 500 3 500 DC V 10 0 38 9 80 0 r min Loaded Cranking ...

Page 171: ...he oil pressure switch 2 Slowly operate the special service tool 3 Check the switch for continuity at the specified pressure Replace if there is no continuity Lighting coil resistance reference data Yellow Y Yellow Y 0 90 1 10 Ω at 20 C 68 F Switch position Lead color White W Black B Clip removed a Clip installed b Engine stop button pushed c S69J8250 Thermo sensor resistance Brown black Br B Brow...

Page 172: ...ecking the LED Other batteries e g alkaline batteries or high voltage batter ies will damage the diode NOTE The LED will not light if the penlight battery voltage is less than 1 5 V The LED only allows current to flow in one direction Therefore if the LED does not light reverse the connection If the oil pressure warning indicator is installed to the outboard motor start the engine and ground the p...

Page 173: ...6D55F11 TRBL SHTG 1 2 3 4 5 6 7 8 9 Troubleshooting Power unit 9 1 ...

Page 174: ...or safe maintenance procedures Power unit 9 Symptom 1 Engine does not start or starting the engine is difficult Manual starter is operating normally Air vent screw on the fuel tank is open Ignition system Check the condition of the spark plugs Clean adjust or replace the spark plugs No Check the ignition spark using the spark gap tester WARNING Do not touch any of the connections of the spark gap ...

Page 175: ...ood condition Replace the ignition coil Yes No Good condition Check the charge coil output peak voltage Replace the stator coil Yes Good spark Check the ignition coil resis tance Check the fuel system No Continued on next page Check the pulser coil output peak voltage or resistance Yes No Good condition Replace the pulser coil Check the CDI unit output peak voltage Power unit ...

Page 176: ... clogs and the hoses for leaks No Yes Clogs debris or wear No Yes Replace the diaphragms Cracks or damage No Repair or replace the defective parts Yes Check the fuel pump dia phragms Clogs or leaks Clean or replace the defective parts Check the ignition system Disassemble the carburetor and check the internal parts for clogs debris or wear ...

Page 177: ...s open Check the throttle cable and link operation Check the ignition system Fuel system Check the fuel pump dia phragms Clogs or leaks Check the fuel filter for clogs and the hoses for leaks Repair or replace the defective parts No Yes Cracks or damage No Yes Check the throttle valve opera tion Replace the diaphragms Good condition Yes No Repair or replace the defective parts Check the pilot scre...

Page 178: ...s No Within specification Adjust the pilot screw Disassemble the carburetor and check the internal parts for clogs debris or wear No Yes Check the ignition system or lubrication system Clogs debris or wear Clean or replace the defective parts ...

Page 179: ...place the oil pressure switch At specified level Debris or leaks Check the engine oil level Yes Check the oil pressure Within specification No Yes Clean or replace the defective parts Check the oil pressure switch Good condition Check the ignition system or the fuel system Yes No No Good condition Check the thermo sensor Yes Replace the thermo sensor Power unit ...

Page 180: ...ance 5 42 Checking the cylinder bore 5 37 Checking the cylinder head 5 29 Checking the diaphragms and valves 4 6 Checking the drive shaft 6 17 Checking the electrical components 8 2 Checking the engine idle speed 3 10 Checking the engine oil 3 4 Checking the engine oil level 1 6 Checking the engine stop lanyard switch 1 9 8 10 Checking the fuel filter 3 3 Checking the fuel joint 4 7 Checking the f...

Page 181: ... 6 12 Disassembling the propeller shaft assembly 6 11 Disassembling the propeller shaft housing 6 11 Disassembling the swivel bracket 7 16 Disassembly and assembly 1 4 Draining the engine oil 7 10 Drive shaft and lower case 6 15 E Electrical 2 7 Electrical components 8 3 F Fire prevention 1 3 Front and aft views 8 3 Fuel hoses and fuel filter 4 3 Fuel pump 4 4 Fuel system 3 3 G General 3 13 Genera...

Page 182: ...moving the steering arm 7 11 Removing the timing belt and sprockets 5 15 Removing the water pump 6 7 Replacing the oil filter 3 5 Replacing the valve guides 5 25 S Safety while working 1 3 Selecting the connecting rod bearing 5 42 Selecting the crankshaft main bearing 5 43 Selecting the forward gear shims 6 25 Selecting the pinion shims 6 24 Selecting the reverse gear shims 6 26 Selection 1 6 Self...

Page 183: ......

Page 184: ...YAMAHA MOTOR CO LTD Printed in Japan Nov 2003 0 4 1 CR E Printed on recycled paper ...

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Yamaha F2.5C, Service Manual

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