Page 3 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 dependable use of the product for long term, it is essential to maintain the performance and quality of the outboard.
Page 4 This service manual is designed so that service persons are able to perform their work correctly. Understand the following matters well for efficient repairs. Each chapter begins with the introduction of special tools that are used for the work described in the chapter so that the service persons are able to figure out the tools needed.
Page 5 This manual uses SI unit system (International System of Units) for pressure, force (load), torque and stress. This manual newly adopts the international unit construction system (SI unit system) followed by the conventional imperial and metric systems enclosed by ( ) and [ ] as described below. <Reference>...
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Page 7 8) Inspection of Water Pump …………… 3-8 9) Replacement of Gear Oil …………… 3-10 1-2 10) Inspection of Gear Case (for leakage) 3-11 1) Fire Prevention …………………………… 1-2 11) Inspection of Timing Belt …………… 3-12 2) Ventilation …………………………………… 1-2 12) Replacement of Timing Belt ………… 3-13 3) Protection ……………………………………...
Page 8 15) Inspection of Cam Shaft ……………… 5-37 4-20 16) Inspection of Cylinder Head ………… 5-38 4-20 17) Inspection of Oil Pump ……………… 5-39 4-21 18) Installation of Valves ………………… 5-40 1) Ignition Timing Controls …………………… 4-21 19) Installation of Cam Shaft …………… 5-41 2) Ignition and Combustion Orders …………...
Page 9 20) Removing Drive Shaft …………………… 6-16 19) Inspection of PTT Pump and Valves …… 7-26 21) Disassembly of Drive Shaft ……………… 6-16 20) Removing Tilt Cylinder …………………… 7-27 22) Inspection of Drive Shaft ………………… 6-17 21) Inspection of Tilt Cylinder ……………… 7-27 23) Disassembly of Forward Gear (A Gear) …...
Page 10 6) Inspection of Brushes ……………………… 8-22 10-5 1) Installation of Meters ………………… 10-5 7) Inspection of Starter Motor Operation …… 8-22 2) Installation of Battery ………………… 10-5 8-23 3) Wiring Diagram of Remote and Control Meters 10-6 1) Inspection of Alternator …………………… 8-23 10-7 2) Inspection of Rectifier ………………………...
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Page 13 2) Gear Shift ……………………………… 1-9 3) Engine Oil ……………………………… 1-9 4) Gear Oil ………………………………… 1-9 1) Fire Prevention …………………………… 1-2 5) Fuel Line ……………………………… 1-10 2) Ventilation …………………………………… 1-2 3) Protection …………………………………… 1-2 6) Rigging ………………………………… 1-10 4) Genuine Parts ……………………………… 1-2 7) Inspection of PTT unit …………………...
Page 14 Engine serial number is stamped on the bottom cowl of outboard motor body. Model Name Model Type Serial Number Gasoline is hazardous material and very flammable. Do not handle gasoline near ignition source such as spark or static electricity. Exhaust gas or gasoline vapor is hazardous for human health.
Page 15 Use specified special tools to prevent damaging to parts and to perform work safely and surely. Be sure to follow installation procedures described in this manual and use tightening torque specified. Remove foreign substances and dirt from outboard motor body and individual parts by cleaning. Apply recommended oil or grease to rotating areas and sliding surfaces.
Page 16 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 17 P/N. 3R0-64110-0 Outer diameter : 223mm With : 11.5mm Rotational speed at WOT Outboard motor model (Wide Open Throttle) (r/min) MFS 25 C approximately 5,200 MFS 30 C approximately 5,700 For the following measuring instruments, use commercially available ones. Circuit tester ( Resistance : 1Ω, 10Ω, 10 kΩ, AC voltage : 30 to 300V, DC voltage : 30V ) Vernier calipers ( M1 type, 300 mm )
Page 18 Spring Pin Tool A Spring Pin Tool B Bevel Gear B Nut Wrench Bevel Gear B Nut Socket P/N. 345-72227-0 P/N. 345-72228-0 P/N. 346-72231-0 P/N. 346-72232-0 Removing spring pin Installing spring pin Removing/installing Pinion Nut (B Gear Nut) Mount Puller Kit Bevel Gear Bearing Installation Tool Thickness Gauge P/N.
Page 19 Oil Filter Wrench Shimming Gauge Driver Rod Universal Puller Plate P/N. 3AC-99090-0 P/N. 346-72250-0 P/N. 3AC-99702-0 P/N. 3AC-99750-0 Measuring pinion gear Removing reverse gear/ Used with center plate and Removing/installing oil filter (B gear) height bearing roller bearing attachment Roller bearing press Ass'y Roller Bearing Attachment P/N.
Page 20 Backlash Measuring Tool Kit Spark Tester Crank Shaft Holder P/N. 3C8-72234-0 P/N. 3F3-72540-0 P/N. 3R0-72815-0 Measuring gap between forward and pinion gears Inspecting sparks Holding crank shaft (A and B gears) Clamp Plier Pressure Gauge Ass'y P/N. 3T5-72864-0 P/N. 3T5-72880-0 Caulking clamp Measuring fuel pressure 4st 25/30 2016...
Page 21 Check installations for clattering and play. Adjust steering friction. Check throttle grip for movement. (full open/full close). Adjust throttle friction. Check that gear shifts from neutral (N) to forward (F) and reverse (R) smoothly. Fill engine with engine oil. 4 Stroke Engine Oil : 1.6 L (1.7 US.qt)[without oil filter replacement] 1.8 L (1.9 US.qt)[oil filter replaced] Use oil level gauge to check oil quantity.
Page 22 Check that fuel tank contains sufficient amount of gasoline, fuel line is connected and is free of leak. Check that clamp bracket is fixed securely to hull. Check location of cavitation plate relative to boat bottom, and, if necessary, adjust to prevent decrease in propulsive force and engine overheating.
Page 23 Press start switch or turn main switch to START check that engine starts. Turn main switch to OFF to check that engine stops. Tiller Handle Model Remote Control Model Press stop switch hard or pull out lock from stop switch to check that engine stops.
Page 24 Check that cooling water check port discharges water during engine runs. After engine has warmed up, use tachometer to check idle speed is as specified. Idle Speed : 850±30 r/min Tachometer : P/N. 3AC-99010-0 High-tension cord Select a propeller that is best-suited to type of boat and application.
Page 25 Adjustment of trim tab angle After installing outboard motor on the boat, use trim tab to achieve balance between port and starboard steering loads. Loosen trim tab bolt, adjust angle of trim tab as described below, and then tighten the bolt to specified torque. Trim tab bolt : 6 N·m ( 5 lb·ft ) 0.6 kg Example of trim tab angle adjustment...
Page 26 Start engine and check if gear shift can be made smoothly. After completing warm-up operation, check idling revolution speed. Idling Revolution Speed : 850±30 r/min Tachometer : High Tension Cord P/N. 3AC-99010-0 Shift gear into forward (F) and run dead slow for approximately 10 minutes.
Page 27 1) Engine Dimensions ………………………… 2-2 2) Transom Bolts ……………………………… 2-3 2-10 2-18 1) ECU Fuel Feed System …………………… 2-4 2-20...
Page 28 F25C F25C Item Type Unit F30C F30C G/PT tilt mm (in) 489 (19.252) 489 (19.252) mm (in) 699.5 (27.539) 699.5 (27.539) mm (in) 847 (33.346) 847 (33.346) mm (in) 974 (38.346) 974 (38.346) mm (in) 404.5 (15.925) 404.5 (15.925) mm (in) 552 (21.732) 552 (21.732) mm (in)
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Page 30 ECU uses various sensors to precisely control injected fuel amount and ignition timing. 4st 25/30 2016...
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Page 32 Thermostat Cylinder Head Cylinder Fuel Cooler Thermostat Cooling Water Cylinder Check Port Cylinder Head Engine Base Fuel Idle Port Cooler Drive Shaft Housing Cooling Water Pipe Cooling Water Check Cooling Water Port Pump Cooling Water Intake Cylinder Lower Section (Water Feed Passage in Engine Base) Exhaust Gas &...
Page 33 Model Item Overall length 1,039 (40.9) (in) Overall width 411 (16.2) (in) Overall height S:1,189 L:1,337 UL:1,464 (S:46.7 L:52.6 UL:57.6) (in) Transom height S:404 L:552 UL:679 (S:15.9 L:21.7 UL:26.7) (in) S:71.5 L:73 S:78 L:79.5 S:74.5 L:76 S:81 L:82.5 UL:75 UL:81.5 UL:78 UL:84.5 Weight...
Page 34 Model Item Overall length 1,303 (51.3) 726 (28.6) (in) Overall width 411 (16.2) (in) Overall height S:1,189 L:1,337 UL:1,464 (S:46.7 L:52.6 UL:57.6) (in) Transom height S:404 L:552 UL:679 (S:15.9 L:21.7 UL:26.7) (in) S:77 L:78.5 S:85 L:86.5 S:73 L:74.5 S:81 L:82.5 UL:80.5 UL:88.5 UL:76.5...
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Page 36 Part Name Item Standard Value Build up of carbon in combustion chamber Cylinder Head Distortion or damage on mating surface Corrosion on the mating surface Cooling water passage clogged Cylinder Deposition in water jacket Wear of bore : Use cylinder gauge to 61.00mm (2.4016in) measure inner diameter.
Page 37 Functional Limit Action To Be Taken Clean to remove. 0.1mm (0.004in) Correct. (Use water proof sand paper of #240 to 400 on the surface plate to level. Use #600 to finish.) Correct if possible, or replace. Clean to remove. Clean to remove. 61.06mm (2.4039in) Replace if over specified limit.
Page 38 Part Name Item Standard Value Intake Valve Valve Clearance 0.15±0.02mm (0.006±0.001in) 0.20±0.02mm (0.008±0.001in) Exhaust Valve Valve Stem Outer Diameter 5.48mm (0.2157in) 5.46mm (0.2150in) Valve Guide Inner Diameter 5.51mm (0.2169in) 5.51mm (0.2169in) Clearance between valve 0.008 to 0.040mm (0.00031 to 0.00157in) guide and valve stem 0.025 to 0.057mm (0.00098 to 0.00224in) Width of contact with...
Page 39 Functional Limit Action To Be Taken Adjust into specified range. 5.46mm (0.2150in) Replace if less than specified limit. 5.44mm (0.2142in) 5.55mm (0.2185in) Replace if over specified limit. 5.57mm (0.2193in) 0.070mm (0.00276in) Replace if over specified limit. 0.100mm (0.00394in) 2.0mm (0.08in) Replace if over specified limit.
Page 40 Part Name Item Standard Value Ignition Timing (at 850 r/min) BTDC 5°±5° Magneto Spark Performance (at 500 r/min) 10mm (0.4in) or over (Use genuine spark tester.) Alternator Output (at 5,000 r/min) 12V-180W Alternator Resistance Exciter Coil Between White/Red and White/Black 11 to 16Ω...
Page 41 Functional Limit Action To Be Taken 10mm (0.4in) Replace if less than specified value. Replace if out of specified range. Replace if out of specified range. Replace if out of specified range. Replace if out of specified range. Clean to remove carbon build up and dirt. Adjust with side electrode. 1.2mm (0.047in) Replace if electrodes are severely worn.
Page 42 Part Name Item Standard Value Valve Operation Starting Temperature (Submerged) 60°C±1.5°C (140±3°F) Thermostat Valve Full Open Temperature (Submerged) 75°C (167°F) Valve Full Open Lift (Submerged) 3.0mm (0.12in) or over Pump Impeller Wear, Crack Pump Case (Liner) Wear Guide Plate Wear Anode Gear Case Anode Consumption Clutch Spring...
Page 43 Functional Limit Action To Be Taken Any opening under ambient temperature Replace if out of specified range. 75°C (167°F) because thermostat operation is delayed. Measure valve open lift after 5 minutes. 3.0mm (0.12in) Replace if less than specified limit. Wear, crack or damage on tips and upper and lower Replace pump case liner and guide plate as a set.
Page 44 Wrench A Screw Size B Tightening Torque Fastened Components Type of Fastener N·m lb·ft kg·m First Tightening Torque : Engine Cylinder Block - Cylinder Head M8 x 1.25 Bolt Final Tightening Torque : First Tightening Torque : M6 x 1.0 Bolt Final Tightening Torque : First Tightening Torque :...
Page 45 Wrench A Screw Size B Tightening Torque Fastened Components Type of Fastener N·m lb·ft kg·m Tilt Cylinder End − − 15.5 Tilt Rod Joint − Reservoir Tank − − Bolt Reserve Cap − − − 0.15 Motor Flange − − Screw 0.25 Manual Valve...
Page 46 Item Name Remarks Part Name Konishi Three Bond Loctite Bond 1342 1373B 1741 1141C G17 LIT OBM 4ST GEAR SOC ATF Cylinder (Liner) Inner Wall Piston Ring Grooves, Periphery, Skirt Piston Rings Periphery Piston Pin Periphery Connecting Rod Big and Small Ends Metal Bearing [Cylinder Block, Crank Case] Both Faces Crankshaft (Thrust Face)
Page 47 Item Name Remarks Part Name Konishi Three Bond Loctite Bond 1342 1373B 1741 1141C G17 LIT OBM 4ST GEAR SOC ATF Filler Cap O-Ring Periphery Solenoid Switch Terminals Spark Plug Insertion Area Plug Cap High Tension Cable Terminals Starter Motor Apply thin coat to pinion.
Page 48 Item Name Remarks Part Name Konishi Three Bond Loctite Bond 1342 1373B 1741 1141C G17 LIT OBM 4ST GEAR SOC ATF Exhaust Plug [D-Shaft Housing] Seal Rubber [Engine Base & Apron] Bolt [Pump Case (Upper)] Thread Pump Case (Upper) Impeller Sliding Area Water Pipe Seal (Lower) Connection Drive Shaft [Housing Side]...
Page 49 15) Inspection of Compression Pressure 3-18 16) Inspection and Adjustment of Valve Clearance 3-19 17) Throttle Cable ………………………… 3-20 1) Inspection of Top Cowl …………………… 3-4 18) Inspection of Shift Lever Gear Operations … 3-24 2) Inspection of Fuel System Piping ………… 3-4 19) Inspection of PTT Unit Operation ……...
Page 50 Spring Pin Tool A Spring Pin Tool B Tachometer Compression Gauge P/N. 345-72227-0 P/N. 345-72228-0 P/N. 3AC-99010-0 P/N. 3AC-99030-0 Measuring engine revolution Measuring compression Removing spring pin Installing spring pin speed pressure Flywheel Puller Kit Torque Wrench Valve Clearance Driver Oil Filter Wrench P/N.
Page 51 Inspection intervals Description First 20 Every 50 Every 100 Every 200 Inspection procedure Remarks hours of hours of hours of hours of 1 month 3 months 6 months 1 year Replace every 200 hrs or High pressure fuel ﬁlter Check for clogged. 2 years Fuel ﬁlter Check for clogged.
Page 52 Push top cowl to check for looseness and state of closing. Check the fuel system piping for fuel leak, dirt, deterioration and damage, and replace or clear parts if necessary. 4st 25/30 2016...
Page 53 Remove fuel pick up elbow of fuel tank counterclockwise to remove the part, and clean the filter . Remove dirt and water from fuel tank if any. Fuel Pick Up Elbow Filter Check fuel filter for dirt, build up of fuel slag, and fuel filter for invasion of foreign matters and crack.
Page 54 Oil Level Quantity of Oil for Full Replacement When oil filter When oil filter is replaced is not replaced Upper Limit 1.8L 1.6L Lower Limit 1.5L 1.3L Oil Specification Recommended Engine Oil : 4 Stroke Engine Oil API : SE, SF, SG, SH, SJ, SL SAE : 10W-30, 10W-40 NMMA : FC-W Certified 10W-30 Quantity of Engine Oil :...
Page 55 Drain engine oil. Place a piece of rag below oil filter area, and remove it by using oil filter wrench • Replace oil filter 5 minutes or more after stopping engine. • Wipe off spilt oil completely. Oil Filter Wrench P/N.
Page 56 Tilt down outboard motor to make it vertical. Remove upper oil plug and check level of gear oil in the gear case. Spill of some oil from plug hole as plug is removed indicates that gear case is filled with specified quantity of gear oil.
Page 57 Remove lower unit installation bolts, and pull lower unit ass'y downward to remove. Remove pump upper case Remove impeller and check it. Check upper pump case for deformation. Replace if necessary. Check impeller and pump case liner for crack and wear.
Page 58 Tilt outboard motor a little as shown. Place drain oil pan below drain bolt , remove lower oil plug and then upper oil plug to drain oil. Remove lower oil plug first when draining. Check gear oil for presence of metal particles, change of color (abnormal if clouded), and viscosity.
Page 59 Drain gear oil. Remove upper oil plug and connect a commercially available leakage tester to this hole. Apply specified pressure to gear base, and check if the pressure is maintained without further compression for 10 seconds. Specified Gear Case Maintained Pressure : 0.069 MPa ( 10 PSi ) [ 0.7 kgf/cm •...
Page 60 Remove upper starter lock cable, and then recoil starter and belt cover. Check timing belt inner and outer surfaces for cracks, damages, wear and oily while rotating flywheel clockwise with hands. Replace if necessary. Reinstall recoil starter and belt cover. Reconnect upper starter lock cable.
Page 61 Disconnect upper starter lock cable. Remove recoil starter, belt cover and starter pulley. Rotate flywheel clockwise to bring " " mark of cam shaft pulley to " " mark of cylinder head. No.1 piston is to be at top dead center of compression stroke.
Page 62 Remove flywheel and then key Screw puller onto crankshaft end until flywheel i s d i s e n g a g e d f r o m t a p e r e d s e c t i o n o f crankshaft.
Page 63 Check that cam shaft pulley's " " mark and cylinder head's " " , and belt guide's " " mark cylinder's " " are aligned with each other respectively. Attach timing belt to timing pulley with its part number side facing upward, and then to cam shaft pulley. If the timing belt is difficult installing, after installing to the timing pulley...
Page 64 Reinstall key and flywheel and tighten nut to specified torque. Flywheel Puller Kit : P/N. 369-72211-0 Flywheel Nut : 150 N·m ( 108 lb·ft ) [ 15 kgf·m ] Reinstall starter pulley, recoil starter and belt cover. Reconnect upper starter lock cable. 3-16 4st 25/30 2016...
Page 65 Remove plug cap and then spark plugs. Use spark plug cleaner or wire brush to clean spark plug electrodes . Replace if necessary. Check electrodes for corrosion or excessive build up of carbon, and washer for damage. Replace if necessary. Check spark plug gap .
Page 66 Start and run engine for 5 minutes to warm up, and then stop. Shift gear into neutral (N). Remove lock plate (stop switch lanyard) from stop switch. Remove all plug caps and then all spark plugs. Install compression gauge to plug hole. Compression Gauge : P/N.
Page 67 ○ • Perform inspection and adjustment of valve clearances when engine is cold. • No.1 piston is to be at top dead center of compression stroke. ▲ Disconnect starter lock cables, and then recoil starter, belt cover, spark plugs, and cylinder head cover. Rotate flywheel clockwise to bring "...
Page 68 Stopper portion and stopper portion of cable bracket of throttle drum is contacted when fully opened as in illustration. Contact. Install throttle cable and adjust it. • Hook on throttle cable to throttle drum and install them to throttle cable brcket •...
Page 69 At the position of the control lever of the control box is neutral (N), free accelerator lever (remote control model) or throttle (multi tiller - handle model) to check that it is position of the fully closed Set remote control lever to forward (F), neutral (N), reverse (R) and then to neutral (N) position.
Page 70 Lock joint with nut , put it on the pin, and secure with washer and snap pin Check that shifting control lever forward (F) by approximately 32 degrees , where it is stopped once, makes the gear engage, and fully shifting the lever makes throttle valve fully open, and then, check that shifting the lever reverse (R) by approximately 32 degrees , where it...
Page 71 Check that throttle valve of throttle body, to contact with fully open stopper when throttle grip to fully open. Check that throttle roller , awy from throttle cam when throttle grip to fully cosed. Check if throttle valve operates smoothly, and repeat steps 1.
Page 72 Shift gear from neutral (N) to forward (F), neutral (N), and then to reverse (R) to check that shift operation is performed smoothly. Adjust if necessary. Remove remote control cable joint from shift lever shaft Remove spring pin of shift rod joint , then disconnect shift and cam rod Spring Pin Tool A...
Page 73 Tilt up and down outboard motor several times to check that PTT unit operates smoothly in full range. Check PTT fluid quantity if necessary. Refer to "Inspection of PTT Fluid Quantity" described in the next page. Check that PTT motor produces noise of normal revolution.
Page 74 Fully tilt up outboard motor and lock with tilt stopper Remove reserve tank cap and check quantity of PTT fluid contained in the tank. Quantity of PTT fluid is normal when some fluid spills out of cap hole when cap is removed. Add recommended PTT fluid to specified level if it is lacking.
Page 75 Start engine and run for 5 minutes to warm up. Attach tachometer to high tension cord to check idle speed. More accurate and stable reading can be obtained when tachometer lead is connected with high tension cords of individual cylinders linked with each other.
Page 76 Check anode and trim tab for build up of scale and adherence of grease and oil. Clean, or replace if necessary. PTT/Gas Assist Model Mechanical Tilt Model When it is necessary to disassemble outboard m o t o r f o r i n s p e c t i o n o f a n o d e , r e f e r t o disassembly described in this manual.
Page 77 Check propeller blades and spline for cracks, damages, wear and corrosion. Replace if necessary. Remove fuel cooler. Remove cover and thermostat Hang thermostat 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 78 Check water strainer and sub water strainer clogging. Clean if necessary. Set outboard motor in the water and start engine. Check that cooling water is discharged from cooling water check port . If not, check water pump and cooling water passage in the engine.
Page 79 Flushing with water using drive cleaner Remove propeller and thrust holder. Close sub water strainer with tape. Attach driver cleaner to water strainer area. Put water hose to driver cleaner and run water. Set gear shift to neutral (N) and start engine. Check that cooling water check port discharges water, and run engine for 3 to 5 minutes at low speed.
Page 80 Inspect electrolyte level. If lower than "LOW" mark , add distilled water until the level goes in between "UP" and "LOW" marks. Measure specific gravity of electrolyte. Charge battery if specific gravity is less than specified value. • Batteries are available with various types, varying among manufacturers.
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Page 83 4-20 4-20 Fuel Hose, Vent Hose, Breather Hose, Cooling Water Hose 4-21 1) Ignition Timing Controls ……………… 4-21 Fuel System …………………………………… 4-4 2) Ignition and Combustion Orders …… 4-21 Intake Manifold ………………………………… 4-6 3) Ignition Timing ………………………… 4-21 Magneto ………………………………………… 4-8 4) Operations ……………………………...
Page 84 Vacuum/Pressure Gauge Clamp Plier Pressure Gauge Ass'y P/N. 3AC-99020-1 P/N. 3T5-72864-0 P/N. 3T5-72880-0 Inspecting pressure Caulking clamp Measuring fuel pressure 4st 25/30 2016...
Page 85 Ref. Description No.. Fuel Hose (Fuel Connector to Fuel Filter) Fuel Hose (Fuel Filter to Fuel Pump) Fuel Hose (Fuel Pump to Vapor Separator) High Pressure Fuel Hose (Vapor Separator to Fuel Cooler) High Pressure Fuel Hose (Fuel Cooler to High Pressure Filter) High Pressure Fuel Hose (High Pressure Filter to T Nipple) High Pressure Fuel Hose (T Nipple to Fuel Rail) High Pressure Fuel Hose (T Nipple to Fuel Regulator)
Page 86 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Vapor Separator Assy 20 Grommet 2 O-ring 21 Washer 6.5-21-1 Do not reuse.
Page 87 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 39 Low Permeation Hose L=100 1 HP Fuel Filter-T-Nipple 58 Low Permeation Hose 1 F/Filter-F/Pump 40 Low Permeation Hose L=340 1 T-Nipple-Fuel Rail...
Page 88 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Intake Manifold Assy 16 O-ring 1.9-9.8 Do not reuse. 17 Holding Plate 2 Dowel Pin 6-12 3 Bolt 5-10 18 Bolt 4 Washer 5.3-12-1 19 Bolt 5 Fuel Rail Assy 20 Clamp 6.5-47.5p 6 O-ring 1.9-4.8 21 Map Sensor 1 Manifold Absolute Pressure Sensor...
Page 89 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 31 O-ring 1.9-31.2 44 Bolt Do not reuse. 32 Bolt 45 Intake Silencer Assy 1 Throttle Body 33 Washer 46 Gasket 34 Nut 47 Bolt 35 Bolt 48 Intake Silencer Assy 1 ISC Valve 36 Fuel Hose 1 ISC Valve-Intake Manifold 49 Intake Silencer Cover...
Page 90 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Flywheel Assy 1 ZF 91 with Ring Gear 20 Clamp 6.5-87P 1 for MF 2 Alternator Assy 21 ECU Bracket Assy 3 Key 19-7-5 1 Magneto 22 Rubber Mount 11.8-14-1.5 4 Nut 18-P1.5 23 Washer 6-16-1.5 5 Washer 19-34-3 24 Collar 6.2-9-7.4...
Page 91 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Oil Pressure Switch 18 O-ring Do not reuse.
Page 92 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 35 Bracket 52 Starter Solenoid 1 for EF/EFT &...
Page 93 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 1-1 Primer Bulb Assy 1 STD 11 Clamp 1-2 Primer Bulb Assy 1 Low Permeation Parts for USA Model 12 Fuel Tank Assy 25L 1 STD 13 Fuel Tank Assy 25L 1 for USA Model 2 Joint Assy (Inlet) 3 Joint Assy (Outlet) 14 Fuel Gauge Vent Cap Assy (25L)
Page 94 ECU uses various sensors to precisely control injected fuel amount and ignition timing. 4-12 4st 25/30 2016...
Page 95 Individual sensors detect engine operating conditions and sends signals regarding the information to ECU. Pulser Coil [Crank Position Sensor] Pulser coils function as crank position sensors. As flywheel rotates, two pulser coils detects crank position in 120 degree range of flywheel and sends the position signals to ECU. ECU uses this signal to establish fuel injection amount and ignition timing.
Page 96 Throttle Position Sensor (TPS) Throttle position sensor is located on the top of throttle body, and is connected to throttle shaft. Throttle position sensor sends throttle open/close information to ECU. Oil Pressure Switch Oil pressure switch is located on the port side of ending, and is projected into oil passage to which pressure between crank shaft and cam shaft from oil pump is applied.
Page 97 Actuator section receives signals from ECU to control air/fuel ratio, ignition timing and idle revolution speed. ISC (Idle Speed Control) Valve ISC is also referred to as IAC (Idle Air Control). ISC valve is an electrical solenoid valve with built-in spring, and controls amount intake air that bypasses closed throttle valve.
Page 98 ECU requires 5VDC for operation. Accidental malfunction of ECU stops engine. ECU provides the following functions. 1. Calculates the most suitable fuel injection amount and ignition timing based on engine revolution speed, throttle position, intake vacuum, intake air temperature and engine cooling water temperature. 2.
Page 99 ECU calculates intake air amount based on engine revolution speed and intake manifold pressure (intake vacuum pressure) to determine fuel injection amount. At engine starting, during warm-up, acceleration/deceleration, and idling, ECU performs correction control based on information from sensors. Fuel injection timings at starting and during normal operation are described in the following table. Cylinder No.
Page 100 At engine starting (cranking), amount of first fuel injection of each cylinder is increased (by extending injection period) to facilitate starting. In addition to this basic correction, information including cooling water temperature, atmospheric pressure and intake air temperature in the manifold from individual sensors are used to correct the engine operation to the best operating conditions.
Page 101 Warning System When an abnormality occurs on the engine, warning buzzer sounds and warning lamp (LED) is lit or blinks. In such case, engine speed is controlled but engine is not stopped. • Warning buzzer : In the remote control box for remote control model, or in the top cowl for tiller handle model. •...
Page 102 For ignition system, pointless CD ignition system is adopted, and ECU's electronic ignition timing control system controls the timing to the most suitable state according to current operating conditions. As engine is cranked, electric current is generated in the alternator's exciter coil and ECU charge coil, which is input to ECU's regulator to feed power needed for operations of ignition coil, fuel injector and fuel feed pump (FFP).
Page 103 ECU's microcomputer is programmed with ignition timings best suited to engine's operating conditions. ECU obtains information about engine operating state such as revolution speed, throttle opening, manifold pressure (air intake vacuum pressure) and cooling water temperature based on the signals from the abovementioned sensors to generate ignition timing signal at the most suitable timings.
Page 104 Fuel pump (low pressure mechanical type) draws fuel from fuel tank , and feed it to fuel feed pump (FFP) located in the vapor separator through fuel connector and fuel filter Highly pressurized fuel passes through fuel cooler and high pressure fuel filter , fed into fuel rail and fuel injector , and then, injected into intake manifold.
Page 105 Fuel pump is diaphragm pump that is operated mechanically by cam shaft. Pump base is plastic components shuts off heat of engine block to protect fuel pump from engine heat. IN : Fuel from Filter/Tank OUT : Fuel Outlet to Vapor Separator Vapor separator feeds only liquid fuel for internal fuel feed pump (FFP) (electrical high pressure pump).
Page 106 Fuel regulator located on the upper section of vapor separator serves to keep regular fuel pressure. Fuel regulator consists of diaphragm with built in spring that actuates valve/seat, and returns (pressurized) excessive fuel to vapor separator when the pressure exceeds certain value. Excessive fuel is returned to vapor separator through internal pipe below fuel level to prevent it from bubbling.
Page 107 Air intake system consists of components including intake manifold (passage to cylinders that is coupled with common air chamber), throttle position sensor , throttle body/shutter , ISC (idle speed control) valve , MAP (manifold pressure) sensor , and MAT (manifold temperature) sensor Intake manifold is provided with fuel rail and fuel injectors.
Page 108 Check the fuel system piping for fuel leak, dirt, deterioration and damage, and replace or clear parts if necessary. Check filter for dirt, build up of fuel slag, and fuel filter cup for invasion of foreign matters and crack. Clean fuel filter cup with gasoline, and replace fuel filter if necessary.
Page 109 Replacement of High Pressure Fuel Filter This filter cannot be disassembled. Replace every 200 hours or 2 years. • Disconnect fuel connector when performing this replacement work. • Attach filter in proper direction. • Be sure to use hose clip. Cleaning Fuel Feed Pump (FFP) Filter Remove filter from fuel feed pump (FFP) located in the...
Page 110 Remove fuel hoses (2) from fuel pump. Connect vacuum/pressure gauge to inlet of fuel pump. Close fuel pump outlet with a finger and apply specified pressure. Check if no air leaks. Vacuum/Pressure Gauge : P/N. 3AC-99020-1 Specified Pressure : 0.049 MPa ( 7 psi ) [ 0.5 kgf/cm With the outlet closed, apply specified vacuum pressure to check that no air leaks.
Page 111 Remove cap Connect pressure gauge as shown. Pressure Gauge Ass'y : P/N. 3T5-72880-0 Start engine run 5 minutes to warm up, and then measure fuel pressure. If the pressure is below specified value, check high pressure fuel passage and vapor separator. Fuel Pressure (Reference) : 0.29 MPa ( 43 psi ) [ 3.0 kgf/cm ] ±10%...
Page 112 Remove cap Connect pressure gauge as shown. Pressure Gauge Ass'y : P/N. 3T5-72880-0 Disconnect thin vent hose from fuel regulator, and connect vacuum/pressure gauge to fuel regulator Vacuum/Pressure Gauge : P/N. 3AC-99020-1 Start engine and keep running at idle revolution speed. Fuel Pressure (Reference) : 0.29 MPa ( 43 psi ) [ 3.0 kgf/cm ] ±10%...
Page 113 Remove cap Connect pressure gauge ass'y as shown, place a vessel below pressure relief hose, and open pressure relief valve to release fuel pressure. Place a vessel below vapor separator drain hose, and loosen drain screw to drain fuel from vapor separator drain hose.
Page 114 Check needle valve for bend and wear. Replace if necessary. Check float for deformation. Replace if necessary. Check filter for dirt and clogging. Clean if necessary. Reinstall needle valve, float and float pin, and check that the parts moves smoothly. Check float drop as shown.
Page 115 Attach float chamber to vapor separator. Reassemble all parts that were removed. Check that hose is reconnected correctly. Use diagnosis system to check operation of ISC (Idle Speed Control) valve. Disconnect hose at intake silencer side of ISC valve, close the hole from which the hose was disconnected with a finger to check if engine speed is reduced.
Page 116 4-34 4st 25/30 2016...
Page 117 15) Inspection of Cam Shaft ……………… 5-37 16) Inspection of Cylinder Head ………… 5-38 17) Inspection of Oil Pump ……………… 5-39 Engine …………………………………………… 5-3 Recoil Starter …………………………………… 5-4 18) Installation of Valves ………………… 5-40 19) Installation of Cam Shaft …………… 5-41 Magneto …………………………………………...
Page 118 Piston Slider Compression Gauge Torque Wrench Valve Clearance Driver P/N. 3AC-72871-0 P/N. 3AC-99030-0 P/N. 3AC-99070-0 P/N. 3AC-99071-0 Measuring compression Installing piston Adjusting valve clearance Adjusting valve clearance pressure Crank Shaft Holder Oil Seal Attachment Flywheel Puller Kit Oil Filter Wrench P/N.
Page 119 Ref. Description Remarks Q'ty 1 Power Unit 2 Oil Level Gauge 3 Gasket Do not reuse. 4 Dowel Pin 5 Bolt 6 M8 L=105mm 6 Apron 7 Screw 2 M6 L=60mm 8 Recoil Starter 9 Belt Cover 10 Battery Cable 4st 25/30 2016...
Page 120 6 N·m (4 lb·ft) [0.6 kgf·m] Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Recoil Starter Assy 16 Friction Spring 17 Starter Lock Cam Spring 2 Starter Case 3 Starter Spring 18 Starter Lock Wire 4 Reel 19 Starter Seal 5 Ratchet 20 Pre-coated Bolt 6-20 6 E-Ring d=10...
Page 121 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 1 Flywheel Assy 1 ZF 91 with Ring Gear 20 Clamp 6.5-87P 1 for MF 2 Alternator Assy 21 ECU Bracket Assy 3 Key 19-7-5 1 Magneto 22 Rubber Mount 11.8-14-1.5 4 Nut 18-P1.5 23 Washer 6-16-1.5 5 Washer 19-34-3 24 Collar 6.2-9-7.4...
Page 122 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Oil Pressure Switch 18 O-ring Do not reuse.
Page 123 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 35 Bracket 52 Starter Solenoid 1 for EF/EFT &...
Page 124 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Vapor Separator Assy 20 Grommet 2 O-ring 21 Washer 6.5-21-1 Do not reuse.
Page 125 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 39 Low Permeation Hose L=100 1 HP Fuel Filter-T-Nipple 58 Low Permeation Hose 1 F/Filter-F/Pump 40 Low Permeation Hose L=340 1 T-Nipple-Fuel Rail...
Page 126 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Intake Manifold Assy 16 O-ring 1.9-9.8 Do not reuse. 17 Holding Plate 2 Dowel Pin 6-12 3 Bolt 5-10 18 Bolt 4 Washer 5.3-12-1 19 Bolt 5 Fuel Rail Assy 20 Clamp 6.5-47.5p 6 O-ring 1.9-4.8 21 Map Sensor 1 Manifold Absolute Pressure Sensor...
Page 127 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 31 O-ring 1.9-31.2 44 Bolt Do not reuse. 32 Bolt 45 Intake Silencer Assy 1 Throttle Body 33 Washer 46 Gasket 34 Nut 47 Bolt 35 Bolt 48 Intake Silencer Assy 1 ISC Valve 36 Fuel Hose 1 ISC Valve-Intake Manifold 49 Intake Silencer Cover...
Page 128 11 N·m (8 lb·ft) [1.1 kgf·m] 64 N·m (46 lb·ft) [6.4 kgf·m] Ref. Description Remarks Q'ty 1 Drive Pulley 1 Timing Pulley 2 Key 13.4-5-4 1 Crankshaft 3 Belt Guide 4 Nut 5 Lock Washer 6 Driven Pulley 1 Camshaft Pulley 7 Key 10-3.7-3 1 Camshaft 8 Washer 6.5-19-3.2...
Page 129 10 N·m ( 7 lb·ft) [1.0 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 30 N·m (22 lb·ft) [3.0 kgf·m] 10 N·m (7 lb·ft) [1.0 kgf·m] 9 N·m (7 lb·ft) [0.9 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.8-8 Fig.5-45 Fig.1-1...
Page 130 10 N·m ( 7 lb·ft) [1.0 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] 30 N·m (22 lb·ft) [3.0 kgf·m] 10 N·m (7 lb·ft) [1.0 kgf·m] 9 N·m (7 lb·ft) [0.9 kgf·m] 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.8-8 Fig.5-45 Fig.1-1...
Page 131 23 N·m (17 lb·ft) [2.3 kgf·m] 30 N·m (22 lb·ft) [3.0 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 6 N·m ( 4 lb·ft) [0.6 kgf·m] 11.5 N·m (8.5 lb·ft) [1.2 kgf·m] Fig.10-1 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Cyl Block &...
Page 132 6 N·m (4 lb·ft) [0.6 kgf·m] 12 N·m (9 lb·ft) [1.2 kgf·m] mark Ref. Description Remarks Q'ty 1-1 Crankshaft Assy 2-2 Plain Shaft Bearing A Red see Service Manual 2 Plain Shaft Bearing A Blue see Service Manual 3 Oil Seal 38-50-8 Upper Do not reuse.
Page 133 Ref. Description Remarks Q'ty 1 Top Cowl Assy (Service) 2 Top Cowl Sub-Assy 3 Top Cowl Seal 4 Roller 6.1-14.7-14 5 E-ring D=5 6 Washer 6.5-21-1 7-1 Decal Set MFS25C 1 25ps 7-2 Decal Set MFS30C 1 30ps 8 Front Decal 9 Caution Decal (A) 10 Caution Decal 1 for EU Model...
Page 134 Run engine 5 minutes to warm up, and then stop. Shift gear into neutral (N). Remove lock plate from stop switch. Remove all plug caps and then all spark plugs. Install compression gauge to plug hole. Compression Gauge P/N. 3AC-99030-0 Fully open throttle, crank engine until compression gauge indication stabilizes, and then measure compression pressure.
Page 135 Spread rag below oil pressure switch. Remove oil pressure switch and connect oil pressure gauge to switch hole. Use commercially available oil pressure gauge. (thread size R1/8) Use the instrument applicable to 1 Mpa (142 PSI ) [ 10 kgf/cm Start engine and run 5 minutes to warm up at idling revolution speed.
Page 136 ○ • Perform inspection and adjustment of valve clearances when engine is cold. • No.1 piston is to be at top dead center of compression stroke. ▲ Disconnect starter lock cables, and then recoil starter, belt cover, spark plugs, and cylinder head cover. Rotate flywheel clockwise to bring "...
Page 137 Disconnect upper and lower starter lock cables. Remove recoil starter, belt cover and starter pulley. Loosen flywheel nut. Loosen flywheel nut before removing power unit to make the work easier. Flywheel puller kit : P/N. 369-72211-0 Disconnect battery cables (2) and PTT motor leads (2).
Page 138 Disconnect PTT switch coupler . (PTT Model) Disconnect throttle link rod Remove oil level gauge Disconnect lower breather hose Disconnect cooling water (fuel cooler) hose and fuel hose Remove apron by removing bolts (2). Remove power unit by removing bolts (6) and then lifting it.
Page 139 Remove flywheel and key. Flywheel puller kit : P/N. 369-72211-0 Screw puller onto crankshaft end until flywheel is disengaged from tapered section of crankshaft. Disconnect alternator and pulser coil. Remove bolts of alternator and coil bracket , and remove alternator and coil bracket. 4st 25/30 2016 5-23...
Page 140 Turn timing pulley clockwise to bring " " mark of belt guide to " " mark of cylinder block, and check that " " mark of cam shaft pulley and " " mark of cylinder head are aligned with each other. No.1 piston is to be at top dead center of compression stroke.
Page 141 Remove timing belt from cam shaft pulley side, and then, from timing pulley side. Remove nut , lock washer , belt guide , timing pulley and key Remove camshaft pulley bolt, then camshaft pulley Check timing belt for crack, damage and wear on both faces.
Page 142 Install cam shaft pulley, bring " " mark of cam shaft pulley to " " mark of cylinder head, and then, tighten bolt to specified torque. No.1 piston is to be at top dead center of compression stroke. Cam Shaft Pulley Bolt 11 N·m ( 8 lb·ft ) [ 1.1 kgf·m ] Install key , timing pulley...
Page 143 Attach timing belt to timing pulley with its part number side facing upward, and then to cam shaft pulley. Reinstall hanger and tighten bolt to specified torque. Hanger bolt : 23 N·m ( 17 lb·ft ) [ 2.3 kgf·m ] Tighten timing pulley nut to specified torque.
Page 144 Turn timing pulley clockwise twice, and check that locating marks , and of pulleys are aligned with each other respectively. 5-28 4st 25/30 2016...
Page 145 • No.1 piston is to be at top dead center of compression stroke. • Removal or installation of parts can be made easier when some of them are assembled together. Remove power unit. (Refer to the section for removing power unit.) Remove fuel system parts from power unit.
Page 146 Remove cylinder head bolts in the reverse sequence of order shown, and remove cylinder head. Remove oil pump ass'y Loosen rocker arm lock nut, and loosen adjusting screw as much as possible. Remove rocker arm , spring, washer and rocker arm shaft •...
Page 147 Compress valve spring by using compressor , remove cotter , and then, spring and valve Valves, springs and other related parts should be arranged in the order they are removed. Valve Spring Compressor Commercially available item Measure valve spring free length .
Page 148 Check valve for dent and wear on the face. Replace if necessary. Measure valve stem outer diameter . Replace if the diameter is less than specified value. Valve Stem Outer Diameter : Standard Value Intake Side : 5.48 mm ( 0.216 in ) Exhaust Side : 5.46 mm ( 0.215 in ) Functional Limit : Intake Side : 5.46 mm ( 0.215 in )
Page 149 Remove carbon built up on the valve. Apply thin coat of red lead on the valve seat. Use valve lapper (commercially available item) as shown to push valve onto valve seat lightly. Measure width of area where valve face contacted with valve seat that can be identified with red lead adhered to valve face.
Page 150 Use valve seat cutter (commercially available item) to correct valve seat. Turn 45 degree cutter clockwise to cut valve seat surface to make it smooth. Be careful not to over-cut valve seat. Turn valve seat cutter while pushing down evenly. Carbon build-up or uneven surface.
Page 151 Use 45 degree cutter to adjust contact width of valve seat to specified value. Width before correction Specified width Valve seat contact area is located on the center, which should be adjusted to specified value by cutting upper and lower ends by using 30 degree and 60 degree seat cutters respectively if the area is too wide.
Page 152 Apply thin coat of abrasive compound on the overall valve seat contact area, and turn valve lapper (commercially available item) while tapping valve. • Use finer abrasive compound to finish. • When changing abrasive compound to finer one, remove present one completely. •...
Page 153 Measure cam height. Replace if the height is less than specified value. Cam Height at Both Intake and Exhaust Sides : Standard Value 25 : 23.87 mm ( 0.9498 in ) 30 : 24.28 mm ( 0.9559 in ) Functional Limit : Cam Height at Both Intake and Exhaust Sides 25 : 23.60 mm ( 0.9291 in ) 30 : 24.00 mm ( 0.9449 in ) Measure cam shaft runout.
Page 154 Remove carbon build-up of combustion chamber, and check for deterioration. Use straight edge and thickness gauge to check distortion of cylinder head in the directions shown. Replace if the distortion is over specified value. Cylinder Head Distortion Limit : 0.10 mm ( 0.004 in ) 5-38 4st 25/30 2016...
Page 155 Use micrometer, cylinder gauge, depth gauge and thickness gauge to measure dimensions shown below. Replace oil pump if over specified value. Functional Limit : Clearance between Outer Rotor and Body 0.25 mm ( 0.0098 in ) Clearance between outer and inner rotors 0.16 mm ( 0.0063 in ) Clearance between sides of rotor and body 0.11 mm ( 0.0043 in ) ( including wear of oil pump cover )
Page 156 Apply oil to valve guide and attach new valve stem seal. Intake Side : Black Exhaust Side : Green Install valve , valve spring seat , valve spring retainer in the order shown, and then, attach valve spring compressor Valve Spring Compressor Commercially available item With valve spring being compressed, use small screw...
Page 157 Apply engine oil to periphery of new oil seal and install it. Driver Rod : P/N. 3AC-99702-0 Oil Seal Attachment : P/N. 3AC-99820-0 Apply grease to lip of oil seal before installing it. Install cam shaft from direction shown. Install rocker arms , springs , washers and collar...
Page 158 Tighten rocker arm shaft locating bolt to specified torque. Rocker Arm Shaft Bolt : 9 N·m ( 7 lb·ft ) [ 0.9kgf·m ] Align cuts of oil pump drive shaft and cam shaft pin with each other to install oil pump Feed engine oil of approximately 2ml to oil passages before installing oil pump.
Page 159 No.1 piston is to be at top dead center of compression stroke. After installing cam shaft pulley, bring " " mark of pulley to " " mark of cylinder head. Check that " " mark of belt guide and " " mark cylinder block are aligned with each other.
Page 160 Remove thermostat cover bolt and the cover Remove oil filter Wipe off spilt oil completely. Oil Filter Wrench : P/N. 3AC-99090-0 Loosen crank case bolts in several steps in the reverse sequence of order shown, and remove crank case. Remove connecting rod bolts and connecting rod cap and then, crankshaft and oil seal.
Page 161 Measure piston outer diameter between points specified. Replace if the diameter is less than specified value. Piston Outer Diameter : Standard Value 60.96 mm ( 2.4000 in ) Measurement Points 9mm ( 0.35 in ) above piston skirt bottom Functional Limit : 60.90 mm ( 2.3976 in ) Measure cylinder inner diameters (D1 to D6) at in crankshaft directions...
Page 162 Measure piston side clearance. Replace piston and piston rings as a set if the clearance is over specified value. Piston Side Clearance : Top Ring : 0.04 to 0.08mm ( 0.0016 to 0.0031 in ) Second Ring : 0.03 to 0.07mm ( 0.0012 to 0.0028 in ) Oil Ring : 0.05 to 0.15mm ( 0.0020 to 0.0059 in ) Functional Limit :...
Page 163 Measure piston pin outer diameter. Replace piston pin if outer diameter is less than specified value. Piston Pin Outer Diameter : Standard Value 16.00 mm ( 0.6299 in ) Functional Limit : 15.97 mm ( 0.6287 in ) Measure piston pin boss inner diameter Obtain clearance between piston pin and pin boss.
Page 164 Measure crankshaft journal outer diameter and crank pin outer diameter . Replace crankshaft if either outer diameter is less than specified value. Crankshaft Journal Outer Diameter : Standard Value 35.99 mm ( 1.4169 in ) Crank Pin Outer Diameter : Standard Value 29.98mm ( 1.1803 in ) Functional Limit : Crankshaft Journal Outer Diameter...
Page 165 Clean connecting rod. Place cylinder block upside down on the work bench. Install piston to connecting rod Do not attach piston rings. Install crankshaft on the cylinder block. Place plasti-gauge on each crank pin parallel to crankshaft. Do not place plasti-gauge on the oil hole of crank pin Install connecting rod and cap...
Page 166 Clean bearings, crankshaft main journal, and bearing installation areas of crank case and cylinder block. Place cylinder block on the work bench with cylinder head side facing downward. Install bearing and crankshaft to cylinder block • Be sure that individual bearings are installed to their original locations.
Page 167 Loosen bolts in reverse order in several steps. Remove crank case and measure width of crushed plasti-gauge on each main journal. Replace bearing if the width is over specified value. Crankshaft Main Journal Oil Clearance : 0.012 to 0.044 mm ( 0.00047 to 0.00173 in ) Functional Limit : 0.060 mm ( 0.00236 in ) If the clearance is less than specified value,...
Page 168 Install connecting , piston pin , and piston pin clip piston • Point "3RO-UP" mark of connecting rod "UP" mark of piston at the same direction. • Be sure to use new piston pin clip, and place clip gap away from piston pin groove shown.
Page 169 Put pistons into cylinder with piston "UP" mark directing flywheel side and piston slider set on the pistons. Before installing, apply engine oil to piston peripheral surfaces, piston rings and piston sliders. Piston Slider P/N. 3AC-72871-0 Install bearing half to cylinder block •...
Page 170 Install bearing half to crank case. • Be sure that individual bearings are installed to their original locations. • Install bearings with their projection fit into crank case groove. Apply 4 stroke engine oil to bearings. Apply sealing agent to mating surface of crank case (both sides, overall).
Page 171 Install oil filter and tighten it to specified torque by using oil filter wrench. Apply thin coat of engine oil to O-ring before installing oil filter. Oil Filter Wrench : P/N. 3AC-99090-0 Oil Filter : 18 N·m ( 13 lb·ft ) [ 1.8 kgf·m ] Install thermostat, new gasket and thermostat cover Install cylinder head.
Page 172 Clean power unit mating surface, and install dowel pin and gasket Install power unit , and tighten bolts in two or three steps to specified torque. Power Unit Installation Bolt : 30 N·m ( 22 lb·ft ) [ 3.0 kgf·m ] Install apron Reconnect breather hose , cooling water (fuel cooler)
Page 173 Reconnect warning lamp, start switch and stop switch. (Tiller Handle Model) Reconnect remote control harness coupler. (Remote Control Model) Install key and flywheel. Flywheel Holder : P/N. 369-72211-0 Flywheel Nut : 150 N·m ( 108 lb·ft ) [ 15.0 kgf·m ] Reinstall recoil starter and belt cover.
Page 174 Adjustment of Starter Lock Cable Shift gear into neutral (N). Check that maximum diameter section of slide is at neutral start mark If not, adjust lower side of cable. Slide Perform shift operation to check that recoil starter is locked Neutral Start Mark at other than neutral (N) position.
Page 175 Remove E-ring , and then, ratchet , ratchet guide and return spring E-Ring Ratchet Guide Reel Return Spring Ratchet Remove starter spring It is not necessary to remove starter spring from starter case if it is not necessary to replace it. Starter spring can be inspected without removing from starter case.
Page 176 Reverse disassembly procedure to assemble by taking care of the following matters. ● When setting starter spring into starter case, face starter spring outer edge hook to the right and set it into peripheral cut of starter case. ● Run starter rope through rope guide ●...
Page 177 17) Disassembly of Clutch Cam and Cam Rod 6-15 18) Inspection of Cam Rod and Clutch Cam 6-16 Gear Case (Propeller Shaft) ………………… 6-4 19) Assembly of Cam Rod and Clutch Cam 6-16 Gear Case (Drive Shaft) ……………………… 6-5 20) Removing Drive Shaft ………………… 6-16 21) Disassembly of Drive Shaft …………...
Page 178 Bevel Gear B Nut Wrench Bevel Gear B Nut Socket Spring Pin Tool A Spring Pin Tool B P/N. 346-72231-0 P/N. 346-72232-0 P/N. 345-72227-0 P/N. 345-72228-0 Removing spring pin Installing spring pin Removing/installing Pinion Nut (B Gear Nut) Bevel Gear Bearing Installation Tool Thickness Gauge Bevel Gear Bearing Puller Ass'y Slide Hammer Kit...
Page 179 Oil Seal Attachment 2 Oil Seal Attachment 3 P/N. 3AD-99820-0 P/N. 3AG-99820-0 Used with driver rod Installing oil Installing pump case (lower) seal in the propeller shaft housing oil seal Backlash Measuring Tool Clamp Bearing Outer Press Kit Roller bearing press Ass'y P/N.
Page 180 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Tapered Roller Bearing 30205 17 Spring Retainer Do not reuse. 2 Propeller Shaft Housing Assy 18 Snap 3 Propeller Shaft Housing 19 Push Rod 4 Roller Bearing 18-25-2.5 20 Ball 3/8 Do not reuse.
Page 181 Projection Hole Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Gear Case Assy 14 Tapered Roller Bearing 32004 Do not reuse. 2 Roller Bearing 20-27-30 15 Water Pump Impeller Do not reuse. 3 Plug 8-8 2 Water Plug 16 Key 20-4.6-2 17 Pump Case (Upper) 4 Gasket 8.1-15-1 2 Water Plug...
Page 182 Projection Hole Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 28-2 Shim 35-41.9-0.15 39 Bolt 1 for Transom L 28-3 Shim 35-41.9-0.3 40 Stud 1 for Transom S 28-4 Shim 35-41.9-0.5 41 Nut 1 for Transom S 29-1 Cam Rod (S) 1 for Transom S 42 Washer 5 Gear Case...
Page 183 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Shift Lever 1 for MF & EF/EFT 14 Bolt 15 Bolt 2 for MF & EF/EFT Throttle Wire Bracket 2 Collar 6.5-10.5-10 1 for MF & EF/EFT 3 Washer 6.5-21-1 1 for MF & EF/EFT 16 Grommet 1 for MF &...
Page 184 Drain gear oil. Refer to "Replacement of Gear Oil" in Chapter 3. Shift gear into neutral (N). Put a piece of wooden block between anti-cavitation plate and propeller to prevent rotation of propeller, and remove propeller nut and then propeller. Split Pin Propeller Nut Washer...
Page 185 Removal of lower unit does not require removal of power unit from outboard motor body. Remove upper side spring pin and disconnect shift rod • Use spring pin tool A to remove spring pin. • Do not reuse removed spring pin. Spring Pin Tool A 345-72227-0 Remove lower unit installation bolts, and pull lower unit ass'y...
Page 186 Check pump case (upper) for deformation. Replace if necessary. Check impeller and pump case liner for crack and wear. Replace if necessary. Check key , water pump guide plate and drive shaft groove for wear. Replace if necessary. Remove bolts and pull out propeller shaft housing ass'y. Puller Claw Commercially available item Puller Plate...
Page 187 Push small bladed screw driver into clutch pin snap remove it while rotating propeller shaft. Then, push clutch lightly while apply preload to push rod to pull out the pin. Remove clutch , push rod , spring retainer and spring •...
Page 188 Tighten universal puller plate to make gap between reverse gear (C gear) and propeller shaft housing. Universal Puller Plate : P/N. 3AC-99750-0 Remove reverse gear (C gear) ass'y by putting two bladed screw drivers into the gap to force the gap to open. Use a press and suitable mandrel to remove ball bearing.
Page 189 When removing only oil seal, use bladed screw driver to pry apart. Use cleaning oil and cleaning brush to clean propeller shaft housing, and check it for crack or damage. Replace if necessary. Check reverse gear (C gear) teeth and clutch for crack or damage.
Page 190 Use a press to push new roller bearing into propeller shaft bearing to specified depth. • Install roller bearing with manufacturer's marking facing reverse gear (C gear) side. • Screw roller bearing attachment into driver gently by using hand without making gap.
Page 191 Remove pump case (lower). Use bladed screw driver to remove oil seal Oil seal Do not reuse. Apply engine oil to periphery of new oil seal, and install into pump case (lower) with number side facing downward. Oil Seal Attachment 3 P/N.
Page 192 Check cam rod and clutch cam for crack and wear. Replace if necessary. Reassemble. Be careful of direction of cam rod. Remove pinion nut (B gear nut), remove drive shaft ass'y and pinion gear (B gear) , and draw out forward gear (A gear).
Page 193 Check drive shaft for bend and wear. Replace if necessary. Measure drive shaft runout. Runout Limit : 0.5 mm (0.020 in) Supporting Points Use two bladed screw driver to remove taper roller bearing from forward gear (A gear). • Remove shim carefully not to damage it because it is reusable.
Page 194 Attach pinion nut (B gear nut) to drive shaft temporarily. Use a press to attach new drive shaft bearing to drive shaft Press collar Commercially available item Inside diameter ø 28 mm (1.102 in) Remove taper roller bearing (outer race) Attach puller claw in the direction as shown.
Page 195 Remove roller bearing by using the following tools. Roller bearing press Ass'y : P/N. 3AC-72900-1 Bearing outer press guide Roller Bearing Press Rod Roller Bearing Press O ring Roller Bearing Press Bolt Bolt M8-110 Collar Washer Roller Bearing Press Flange "...
Page 196 Check skeg area and torpedo-like area for crack and damage. Replace if necessary. Perform shim adjustment when taper roller bearing, gear, drive shaft, propeller shaft or gear case is replaced. Install cam rod ass'y as shown. Cam Rod Bushing Bolt : 6 N·m ( 4 lb·ft ) [ 0.6 kgf·m ] 6-20 4st 25/30 2016...
Page 197 Install roller bearing by using the following tools. Roller bearing press Ass'y : P/N. 3AC-72900-1 Bearing Outer Press Guide Roller Bearing Press Rod Roller Bearing Press O ring Roller Bearing Press Guide Roller Bearing Press Bolt Bolt M8-110 Collar Washer Roller Bearing Press Flange ·...
Page 198 Install spring guide Install new taper roller bearing (outer race) Perform shim adjustment when taper roller bearing, gear, drive shaft, propeller shaft or gear case is replaced. Bearing Outer Press Kit : P/N. 3B7-72739-1 After installing forward gear (A gear), install drive shaft ass'y , pinion gear (B gear) and pinion nut (B gear nut), and tighten the nut to specified torque.
Page 199 Before measuring back lash of each gear, measure drive shaft pinion (B) gear height and adjust the height to proper value if necessary. In accordance with procedure described in “Assembly of Lower Unit” steps 2 to 7 on Chapter 6, install the parts up to pump case , and secure it by using M6 bolt (L=25mm) and flat washer...
Page 200 Add shim to bottom of pump case (lower) to adjust the gap to specified value. Pinion (B) Gear Height 0.60 - 0.64 mm (0.0236 - 0.0252 in) Type of Shims Applicable : 0.1 mm (0.0039 in) 0.15 mm (0.0059 in) 0.3 mm (0.0118 in) 0.5 mm (0.0197 in) 6-24...
Page 201 Backlash Measuring Tool Kit : P/N. 3C8-72234-0 Shaft P/N. 345-72723-0 O-Ring P/N. 332-60002-0 Collar P/N. 346-72245-0 Plate P/N. 3A3-72713-0 Conical Disc Spring P/N. 3B7-72734-0 Clamp P/N. 3B7-72720-0 Pump Case (Lower) Pinion Gear (B Gear) Perform measurement of backlash between forward gear (A gear) and pinion gear (B gear) with propeller shaft housing, propeller shaft and reverse gear (C gear) removed from gear case.
Page 202 Perform shim adjustment as necessary based on the gauge Gauge Reading Shim Adjustment value obtained. The table shows relation between dial gauge readings and shim adjustments. 0.00 to 0.05 – 0.15 1. Va l u e s i n t h i s t a b l e i n d i c a t e d i a l g a u g e 0.06 to 0.20 –...
Page 203 After installing drive shaft ass'y , pinion gear (B gear) and pinion nut (B gear nut), and tighten the nut to specified torque. Bevel Gear B Nut Socket P/N. 346-72232-0 Bevel Gear B Nut Wrench P/N. 346-72231-0 Pinion Nut (B Gear Nut) : 35 N·m ( 25 lb·ft ) [ 3.5 kgf·m ] After settling pinion gear (B gear) height and forward gear (A gear) backlash, apply "Three...
Page 204 Remove pump case (lower) and apply OBM grease to oil seal. Attach new O-ring and pump case (lower) Attach new gaskets , water pump guide plate and dowel pin Use plastic hammer to install key to drive shaft. Bring impeller groove to key and install impeller to drive shaft.
Page 205 Install pump case (upper) ass'y on the gear case, and tighten bolts in two or three steps to specified torque. Apply grease in the interior of pump case liner, and install pump case (upper) by pushing it down with hand while turning drive shaft clockwise.
Page 206 Set cam rod to reverse (R) position. Connect water pipe securely. Move flywheel a little or shift gear into reverse (R), install propeller, and turn propeller shaft counterclockwise to engage spline. Attach lower unit ass'y to drive shaft housing, and tighten lower unit installation bolts to specified torque.
Page 207 Set both engine side and gear case side gear shifts to neutral (N). Connect shift rod and cam rod with new spring pin. Spring Tool P/N. 345-72228-0 Apply grease to propeller shaft. Attach thrust holder, propeller, washer and propeller nut to propeller shaft.
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Page 209 12) Removing Clamp Bracket (PTT or Gas Assistant Model) 7-23 13) Removing Clamp Bracket (Mechanical Tilt Model) 7-23 14) Installation of Clamp Bracket (PTT or Gas Assistant Model) … 7-24 Drive Shaft Housing …………………………… 15) Installation of Clamp Bracket (Mechanical Tilt Model) 7-24 Swivel Bracket (Mechanical Tilt) ………………...
Page 210 Mount Puller Kit P/N. 3AC-72760-0 Removing upper mount 4st 25/30 2016...
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Page 212 31 N·m (22 lb·ft) [3.1 kgf·m] 30 N·m (22 lb·ft) [3.0 kgf·m] Fig.1-16 Fig.6-73 Fig.3-49 30 N·m (22 lb·ft) [3.0 kgf·m] 19 18 31 N·m (22 lb·ft) [3.1 kgf·m] 19 N·m (14 lb·ft) [1.9 kgf·m] 24 N·m (17 lb·ft) [2.4 kgf·m] Fig.12-45 Fig.12-46 19 N·m (14 lb·ft) [1.9 kgf·m]...
Page 213 M/G/PTT Model 41 N·m (30 lb·ft) [4.1 kgf·m] P type 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.18 F type 11 N·m (8 lb·ft) [1.1 kgf·m] 84 85 6 N·m (4 lb·ft) [0.6 kgf·m] 13 14 21 N·m (15 lb·ft) [2.1 kgf·m] 11 12 41 43 12 11...
Page 214 M/G/PTT Model 41 N·m (30 lb·ft) [4.1 kgf·m] P type 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.18 F type 11 N·m (8 lb·ft) [1.1 kgf·m] 84 85 6 N·m (4 lb·ft) [0.6 kgf·m] 13 14 21 N·m (15 lb·ft) [2.1 kgf·m] 11 12 41 43 12 11...
Page 215 M/G/PTT Model 41 N·m (30 lb·ft) [4.1 kgf·m] P type 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.18 F type 11 N·m (8 lb·ft) [1.1 kgf·m] 84 85 6 N·m (4 lb·ft) [0.6 kgf·m] 13 14 21 N·m (15 lb·ft) [2.1 kgf·m] 11 12 41 43 12 11...
Page 216 F type Fig.12 P type Fig.18 Fig.12 Fig.12 Fig.12 Fig.12 Fig.12-9 22 4 Fig.12 GAS ASSIST 11 N·m (8 lb·ft) [1.1 kgf·m] Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1-1 Clamp Bracket (PTT-R) 1 for Gas Assist Model Starboard Side 12 Collar 10.2-12-12 1-2 Clamp Bracket (PTT-R) 1 for EFT Starboard Side...
Page 217 F type Fig.12 P type Fig.18 Fig.12 Fig.12 Fig.12 Fig.12 Fig.12-9 22 4 Fig.12 GAS ASSIST 11 N·m (8 lb·ft) [1.1 kgf·m] Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 24 C-ring d=18 37 Rigging Bolt Set Do not reuse. 25 Clamp 6-9.5L 1 for PTT Model 38 Bolt 12-105 P1.25...
Page 218 35 N·m (18 lb·ft) [3.5 kgf·m] 155 N·m (112 lb·ft) [15.5 kgf·m] Fig.13-14 5 N·m (4 lb·ft) [0.5 kgf·m] 1.5 N·m (1.1 lb·ft) [0.15 kgf·m] Chamfered 2.5 N·m (1.8 lb·ft) [0.25 kgf·m] 5.5 N·m (4 lb·ft) [0.55 kgf·m] 2 N·m (1.5 lb·ft) [0.2 kgf·m] Ref.
Page 219 Fig.17-18 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.17-18 21 20 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 1 Tiller Handle Sub-Assy 14 Bolt 3 Stud 15 Plastic Rivet 6.5 16 Throttle Decal 4 Grip 5 Throttle Shaft 17 Bushing 6 Throttle Shaft Damper 18 Washer 39-52-1 19 Wave Washer 39.5-52-1.2...
Page 220 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.6-28 Fig.6-60 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Bottom Cowl 14-3 Grommet 17-2.7 3 for MF/EP 2 Mount 8.5-14-2.5 15 Grommet 3 Spacer 6.2-9-15.7 16 Grommet 1 for MF/EF/EFG 4 Hook Lever 17 Grommet 1 for EP/EPT 5 Seal Ring 13.8-22-3.7...
Page 221 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.6-28 Fig.6-60 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 28 Stop Switch Decal 1 for F Type 42 Neutral Switch Actuator 1 for EF/EP 29 Grommet 1 MF/EP/EF/EFG 43 Neutral Switch Bracket 1 for EF/EP 30 Flushing Connector 44 Bolt 1 for EF/EP...
Page 222 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Shift Lever 1 for MF & EF/EFT 14 Bolt 2 Collar 6.5-10.5-10 1 for MF & EF/EFT 15 Bolt 2 for MF & EF/EFT Throttle Wire Bracket 3 Washer 6.5-21-1 1 for MF & EF/EFT 16 Grommet 1 for MF &...
Page 223 Check operation of throttle cable. Check throttle cable inner wire and outer wire for bend and damage. Replace if necessary. Attach cables to throttle shaft as shown. Install throttle shaft with cable to tiller handle. Be careful of location of throttle friction Install bushing on the steering bracket Attach tiller handle ass'y to steering bracket...
Page 224 Stopper portion and stopper portion of cable bracket of throttle drum is contacted when fully opened as in illustration. Contact. back side Install throttle cable and adjust it. • Hook on throttle cable to throttle drum and install them to throttle cable brcket •...
Page 225 Assemble co-pilot plate and tiller handle ass'y. Move co-pilot handle to the left to slide it to tightening position. Tighten nylon nut until steering load becomes heavy. Tighten nylon nut to approximately 6 N·m ( 4 lb·ft ) [ 0.6 kgf·m ] and check steering load. Move co-pilot handle to the right to slide it to release position, and check that steering can be made lightly.
Page 226 Turn down lock plate tab , remove upper mount nut and then, remove drive shaft housing ass'y When remove or installing drive shaft housing with power unit installed on the outboard motor, perform the work with outboard motor hung to lighten load applied to upper mount bolt Pull out upper mount by using mount puller kit.
Page 227 Remove engine base from drive shaft housing ass'y Remove plunger from engine base ass'y Remove oil strainer from engine base ass'y Before removing engine base ass'y, note arrangement of oil strainer hose. Remove water pipe from drive shaft housing Check filter for dirt and sediment. Clean, or replace if necessary.
Page 228 Install oil strainer on the engine base , and secure it with ties. Install plunger on the engine base, and tighten it to specified torque. Plunger 30 N·m ( 22 lb·ft ) [ 3.0 kgf·m ] Install new gasket and engine base ass'y to drive shaft housing When installing engine base, be careful not to...
Page 229 Insert upper mount bolt and lower mount bolt into swivel bracket ass'y (upper and lower). Put upper mount nut and tighten nut to specified torque. Lock nut with lock tab Upper Mount Nut 21 N·m ( 15 lb·ft ) [ 2.1 kgf·m ] Put lower mount nut and tighten to specified torque.
Page 230 Put thrust plate and bushing onto steering shaft Stand swivel bracket ass'y vertically, and insert steering shaft into swivel bracket ass'y Put bushing , new O-ring and thrust plate on the steering shaft O-Ring Do not reuse. Assemble steering shaft and mount bracket in the same directions...
Page 231 Put grease through grease nipple until grease leaks from bushing (upper) Remove PTT unit or gas shock absorber. Refer to "Removing PTT Unit/Gas Shock Absorber" described later in this chapter. Remove nylon nut , and then, clamp bracket and swivel bracket Remove shaft from clamp bracket...
Page 232 Install swivel bracket shaft to clamp bracket Assemble swivel bracket and clamp bracket , and tighten nylon nut to specified torque. Nylon Nut 24N·m ( 17 lb·ft ) [ 2.4kgf·m ] Install PTT unit or shock absorber. Refer to "Installation of PTT Unit/Shock Absorber".
Page 233 Fully tilt up outboard motor and lock with tilt stopper • If PTT unit will not operate, open manual valve and lift up outboard motor with hands. • When manual valve is opened, be sure to tighten it with specified torque after tilting up outboard motor.
Page 234 Remove reservoir tank , PTT motor , O-ring coupling from PTT unit Energize removed PTT motor to check that it operates. If not, replace PTT motor ass'y. Remove manual valve and then PTT pump ass'y Remove valves from PTT unit Be careful not to lose removed parts which are small.
Page 235 Retract tilt rod. Use vise to fix PTT unit that is protected at both sides with wood pieces or aluminum plates Secure joint and loosen nut by using wrench, and remove joint and nut Use 36mm deep socket to loosen tilt cylinder , stretch tilt rod and remove tilt cylinder Loosen tilt cylinder with tilt rod retracted, and...
Page 236 Check tilt rod ass'y check valve and valves for dirt and sediments. Clean if necessary. Use vise to fix PTT unit that is protected at both sides with wood pieces or aluminum plates. Assemble valve and PTT pump ass'y , and tighten bolt to specified torque.
Page 237 Assemble new O-rings , coupling , PTT motor ass'y and reservoir tank , and tighten bolt specified torque. Reserve Tank Bolt : 5 N·m ( 4 lb·ft ) [ 0.5 kgf·m ] Put new O-ring on the tilt cylinder Put new dust seal on the tilt cylinder When putting parts in the inner tube, put them from the other side of chamfered end of the...
Page 238 Add PTT fluid to the first step of bottom of tilt cylinder installation hole. Recommended PTT Fluid : ATF DEXRON III Put ass'y of tilt cylinder , tilt rod , inner tube , free piston and O-ring in the PTT unit Install tilt cylinder and tighten to specified torque.
Page 239 Turn manual valve counterclockwise fully. Manual Valve : 2 N·m ( 1.5 lb·ft ) [ 0.2 kgf·m ] Place PTT unit vertically. Remove cap and check fluid level in the reservoir tank. Spill of some fluid from plug hole as cap is removed indicates that gear case is filled with specified quantity of gear oil.
Page 240 Reverse connection of PTT motor lead wires to battery terminals to fully stretch tilt rod. Tilt Rod PTT Motor Lead Wires Battery Terminals Blue (L) + : Positive Terminal Stretch Green (G) – : Negative Terminal • Repeat above steps several times to move up and down tilt rod (When reversing motor lead wire connection, keep the connection open for two or three seconds.).
Page 241 Fully tilt up outboard motor and lock with tilt stopper Reinstall bushings to their original positions. Install PTT unit or gas shock absorber , and then cylinder shaft (lower) Retract tilt rod a little. Attach "C" ring Connect lead wires to battery to fully stretch tilt rod. Install cylinder shaft (upper) and tighten bolt Bushings...
Page 242 Install outboard motor on the boat. Fully tilt up outboard motor and lock with tilt stopper. Remove cap and check fluid level in the reservoir tank. Turn manual valve counterclockwise fully. Tilt up outboard motor fully with hands and let it tilt down gravitationally.
Page 243 Add recommended PTT fluid to specified level if it is lacking. Recommended PTT Fluid : ATF DEXRON III Reservoir tank cap and tighten to specified torque. Reserve Tank Cap : 1.5 N·m ( 1.1 lb·ft ) [ 0.15 kgf·m ] Repeat steps from 5.
Page 244 Check electrical conductivity between terminals . If non conductive, replace DOWN side PTT solenoid. Check electrical conductivity of PTT switch. Replace if other than specified conditions. Lead Wires Switch Position Sky Blue (Sb) Red (R) Pink (P) UP (Tilt Up) Free DOWN (Tilt Down) 7-36...
Page 245 9) Inspection of Start Switch (Tiller Handle Model) … 8-16 10) Inspection of Stop Switch ………………… 8-17 Port Side View ………………………………… 8-3 8-18 Bow Side View ………………………………… 8-4 1) Inspection of Injectors ……………………… 8-18 Starboard Side View …………………………… 8-5 2) Inspection of ISC Valve …………………… 8-18 Top View …………………………………………...
Page 246 Vacuum/Pressure Gauge Spark Tester P/N. 3AC-99020-1 P/N. 3F3-72540-0 Inspecting pressure Inspecting sparks 4st 25/30 2016...
Page 247 Fuel-Feed-Pump-(FFP) : Interior-of-Vapor-Separator Starter-Motor Oil-Pressure-Switch Water-Temperature-Sensor Ignition-Coil 4st 25/30 2016...
Page 248 Starter Motor Throttle Position Sensor Fuel Feed Pump (FFP) : Interior of Vapor Separator ISC (Idle Speed Control) Valve Starter Solenoid Warning Buzzer 4st 25/30 2016...
Page 249 Injector ECU (Electronic Control Unit) MAP (Manifold Pressure) Sensor Rectifier 4st 25/30 2016...
Page 250 ＃1 ＃２ Rectifier Ignition Coil PTT Solenoid Pulser Coils Starter Motor Fuse (20A) MAP (Manifold Pressure) Sensor Alternator (Exciter Coil/Charge Coil/ECU Charge Coil) Starter Solenoid Water Temperature Sensor 4st 25/30 2016...
Page 251 Neutral Switch (Tiller Handle, Electric Start Model) Warning Lamp (LED) PTT Switch (PTT Model) Stop Watch Neutral Switch (Tiller Handle, Electric Start Model) 4st 25/30 2016...
Page 252 Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks 1 Flywheel Assy 1 ZF 91 with Ring Gear 20 Clamp 6.5-87P 1 for MF 2 Alternator Assy 21 ECU Bracket Assy 3 Key 19-7-5 1 Magneto 22 Rubber Mount 11.8-14-1.5 4 Nut 18-P1.5 23 Washer 6-16-1.5 5 Washer 19-34-3 24 Collar 6.2-9-7.4...
Page 253 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Oil Pressure Switch 18 O-ring Do not reuse.
Page 254 8 N·m (6 lb·ft) [0.8 kgf·m] 22 N·m (16 lb·ft) [2.2 kgf·m] 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-36 44 39 44 43 13 N·m (9 lb·ft) [1.3 kgf·m] Fig.5-56 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 35 Bracket 52 Starter Solenoid 1 for EF/EFT &...
Page 255 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 1 Vapor Separator Assy 20 Grommet 2 O-ring 21 Washer 6.5-21-1 Do not reuse.
Page 256 Fig.5-5 6 N·m (4 lb·ft) [0.6 kgf·m] Fig.16-23 Fig.10-21 Fig. 16-21 Fig. 16-22 EXPOSURE Fig.1-1 Fig. 16-23 Use clamp plyer. (P/N. 3T5-72864-0) Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 39 Low Permeation Hose L=100 1 HP Fuel Filter-T-Nipple 58 Low Permeation Hose 1 F/Filter-F/Pump 40 Low Permeation Hose L=340 1 T-Nipple-Fuel Rail...
Page 257 Disconnect plug caps from spark plugs. Connect plug cap to spark tester. Connect spark tester clip to spark plug tip electrode. Spark Tester : P/N. 3F3-72540-0 Spark Performance : 10 mm (0.4 in) or over Start engine and check sparks. Check spark system when sparks are weak.
Page 258 Remove ignition coil coupler. Measure ignition coil resistance. Replace if other than specified value. This test can be made without removing parts. Ignition Coil Resistance : Primary Coil : Between Black/White (B/W) - Black (B) 0.17 to 0.23 Ω (at 20°C) Secondary Coil : Between High Tension Cord - Black (B) 3.3 to 4.9 Ω...
Page 259 Disconnect starboard side #1 pulser coil coupler (2 pin). Measure #1 pulser coil resistance. Replace if other than specified value. Disconnect port side #2 pulser coil coupler (1 pin), and check #2 pulser coil like #1 coil. This test can be made without removing parts. Pulser Coil Resistance (Reference Value) : (#1, #2) #1 Pulser Coil (2 Pin) Between Red/White (R/W) - Black (B)
Page 260 Remove water temperature sensor to test it as a separate unit. Remove water temperature sensor from engine. Put water temperature sensor in the water, and warm up water slowly. Measure water temperature sensor resistance. Replace if the resistance is out of specified range. Water Temperature Sensor Resistance (Reference Value) : Between Black/Yellow (B/Y) - Black (B) 2.4 to 2.9 Ω...
Page 261 Check electrical conductivity of stop switch. Replace if no conductivity. This test can be made without removing parts. Lead Wire Color Switch Position Brown (Br) Black (B) Remove lock. Install lock. Press switch. 4st 25/30 2016 8-17...
Page 262 Measure injector resistance. • This test can be made without removing parts. • Injector operation test can be made by using "Function, or Running (Drop) Stop Test" of diagnosis system. Injector Resistance (Reference Value) : (at 20°C) 11.1 to 12.3 Ω Connect vacuum/pressure gauge to ISC valve.
Page 263 Measure ambient temperature. C o n n e c t c o m p u t e r t o o u t b o a r d m o t o r, a n d u s e diagnosis system to display "Air Temperature (Intake Air Temperature)".
Page 264 Check electrical conductivity of fuse. Replace if no conductivity. Flat or small sized plate fuse (20A) is adopted. Connect tester lead wires to both terminal of starter solenoid. Connector green (G) lead wire to battery positive terminal. Connector black (B) lead wire to battery negative terminal. Check electrical conductivity between terminals of starter solenoid.
Page 265 Check pinion teeth for crack and wear. Replace if necessary. Fix clutch , and turn only pinion to check that it can be rotated smoothly in one direction. Replace if necessary. Turn pinion counterclockwise to check that it can be rotated smoothly. Also, check that pinion is locked when turned clockwise.
Page 266 Measure brush length. Replace brush holder ass'y if brush length is less than specified value. Brush Length : Standard Value 12.5 mm ( 0.492 in ) Wear Limit 9.5 mm ( 0.374 in ) Check conductivity of brush holder ass'y. Replace if other than specified value.
Page 267 Disconnect alternator coupler (3 pin). Measure alternator resistance. Replace if other than specified value. This test can be made without removing parts. Alternator (Charge Coil) Resistance : Reference Value (at 20°C) Between Yellow (Y) and Yellow (Y) (three types) 0.29 to 0.43 Ω Alternator (3 Pin) (Charge Coil) Alternator (6 Pin) (Exciter Coil, ECU/Charge Coil) •...
Page 268 • Check wire harness for disconnection of lead wire and defective connection. • Terminals are arranged and numbered as shown. • The following table names of terminals, their numbers and lead wire colors. Name Terminal Leads Wire (Color) Power Supply (INJ/FFP/ISC/Lamp) Blue Exciter Coils White/Red...
Page 269 1) Diagnosis Software Install ………… 9-20 2) Installing USB to serial converter State 1 : Engine will not start or is a little hard to start. driver (If there is no RS232 port) … 9-21 2.Hardware Connection ………………… 9-22 Starting System ……………………………… 9-3 1) Preparation ……………………………...
Page 270 * Low speed ESG operates. Probable Cause Fuel level is low in the tank. Fuel system connection is incomplete. Fuel system sucks air. Fuel pipe is twisted. Cap vent is closed. Fuel filter, fuel pump or injector is clogged. Low quality gasoline is used. Primer bulb is clogged.
Page 271 Before working on the engine, check that full, rigging and engine installation are normal, and then battery is fully charged. 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 works safely.
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Page 287 Read this manual thoroughly, connect diagnosis cable to computer, and then, perform software operations. • Check that computer is normal. • Fully charge battery. • Clean battery terminal to remove dirt and corrosion, and connect Diagnnosis tool kit battery cables securely. P/N.
Page 288 After entering the dealer-only page, then click the download of diagnostic software. Double-click the "diag". Double-click the "install". Click "Next". Click "Next" put a check in "to create a shortcut to Desktop." Shortcut of diagnostic software is created on the desktop by clicking the "Finish".
Page 289 By the manufacturer of the serial converter, how to install the driver of the serial converter is also vary depending on the computer you are using. The following is an example, detailed procedure of installation to refer to the instruction manual of the converter to be used. Connect serial adapter to USB port (It should be a mark on the USB port which connects to for later).
Page 290 Diagnosis Harness Battery (12V) Computer RC232C Port (9 Pins) USB Port *RS232C Port (9 Pins) If your computer is not provided with RS232C Port (9 Pins), use USB conversion cable as shown. • When using USB conversion cable, install necessary software in accordance with the instructions, and then, proceed to next operation.
Page 291 In principle, use 3AC DIAGNOSIS with the switch set to OFF. Use ON position only for function test and running (drop) test. OFF : Test history is updated. Use this position for other than function test and running (drop) test. ON : Test history is not updated.
Page 292 Double-click "3AC_DIAGNOSTICS" in "PROGRAM" or its short-cut icon. Model select appears. Use " ↑ " or " ↓ " key on the keyboard or press the "1" to "9" number to move cursor to list to be executed, and press "Enter" key. Thoroughly read notes described in "Set Up"...
Page 293 • COM port of the following "5" in the automatic is assigned. • COM port of 5 or less is used when all the diagnostic cable is not connected switches to manual setup screen (next page). * it is necessary to turn ON the engine key. 4st 25/30 2016 9-25...
Page 294 "Com port No = " Current COM port number appears. "New Com Port No = " New COM port number can be input. Input COM port number of your computer. Press "Enter" key to return to "Menu" screen. • Current COM port number can be known by going through "Control Panel"...
Page 295 Current states of engine can be seen on the screen. Press "F1" key to return to "Menu" screen. ※1 ※2 *1 Currently, it is displayed as "failure" if the problem has occurred. *2 If there is a problem in the past, I indicates the time at which the failure occurred at the end.. 4st 25/30 2016 9-27...
Page 296 Malfunction history of engine can be seen on the screen. Press "F1" key to return to "Menu" screen. ※1 ※2 ※3 ※4 ※5 *1 Engine temperature is raised or how much to the highest in the past as shown. In addition, the time of occurrence. *2 Number of times that something goes ploblem.
Page 297 Set switch of diagnosis harness to "ON" when performing function test. Malfunction of injectors or their operating state can be checked. Enter the number of item to be checked. "1" : Operation (on/off) of #1 injector "2" : Operation (on/off) of #2 injector "3"...
Page 298 Set switch of diagnosis harness to "ON" when performing function test. This test stops operation injector or ignition coil temporarily during engine operation for checking operating state according to reduction or operating noise level and engine speed. Enter the number of item to be diagnosed. "1"...
Page 299 Description of error code appears on the screen. Example : Error code : 1 Communication Error Communication with ECU is not ready. Check following items. * Connection between computer and ECU * Connection with battery * Setting of computer COM port number. Use "Setup Communication port"...
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Page 301 10-2 10-7 1) Installation of Remote Control Cable (Engine Side) 1) Warning Indication …………………… 10-7 Remote Control Model …………………… 10-2 10-5 1) Installation of Meters ……………………… 10-5 2) Installation of Battery ……………………… 10-5 3) Wiring Diagram of Remote and Control Meters … 10-6...
Page 302 Turn hook lever on the bottom cowl downward and remove top cowl. Remove cable joint snap pins and washers from throttle side and shift side , and then, remove two cable joints. Screw cable joint on the tip of remote control cable by approximately 10mm.
Page 303 Set remote control lever to neutral (N) , and check that neutral throttling lever is at full close position Set shift arm to forward (F), neutral (N), reverse (R) and then to neutral (N) positions. Set shift drum to full open position. Necessary to keep full throttle position for hands.
Page 304 Check that shifting control lever forward (F) by approximately 32 degrees ( ) , where it is stopped once, makes the gear engage, and fully shifting the lever makes throttle valve fully open, and then, check that shifting the lever reverse (R) by approximately 32 degrees ( ), where it is stopped once, makes the gear engage, and fully shifting the lever makes throttle valve fully open.
Page 305 When installing meters, select a place on the dash board where operator can watch them easily and they are not exposed to water spray. The meters can be installed on the dash board of 2 to 11mm thick. When the thickness is over 11mm, cut fitting plate so that the meters can be installed.
Page 306 Color Code B : Black L : Blue Lg : Light Green O : Orange P : Pink R : Red Sb : Sky Blue W : White Y : Yellow G : Green Y/R : Yellow/Red/ G/R : Green/Red Note : Leads marked with are connected with meter lamp switch...
Page 307 When an abnormality occurs on the engine, warning buzzer sounds and warning lamp is lit or blinks. Take actions described below if abnormal state has occurred. When engine started, warning lamp is lit for 5 seconds and warning buzzer operates for two seconds (generating intermittent sound) indicating that operation warning system is operating normally.
Page 308 Oil Pressure Warning When Oil pressure is reduced below setting value during operation, warning buzzer operates (generating continuous sound), warning lamp is lit, and at the same time, low speed ESG operates to reduce the speed to 2,800r/min or less. •...
Page 309 11-2 11-11 11-3 11-13 11-5 11-15 11-7 11-17 11-9...
Page 310 Name Remarks Lead Wire Color Flywheel Magneto – – – – Exciter Coils Located in the alternator White/Blue White/Black White/Red – – ECU Charge Coil Located in the alternator White White Charge Coil Located in the alternator – Yellow Yellow –...
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Page 319 Copyright © 2016 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 320 Address : 5-4, Azusawa 3-Chome, Itabashi-Ku Tokyo, Japan Phone : TOKYO +81-3-3966-3117 FAX : TOKYO +81-3-3966-2951 URL : www.tohatsu.co.jp...

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