TOHATSU MFS 60A Service Manual
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TOHATSU MFS 60A Service Manual

TOHATSU MFS 60A Service Manual

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S E R V I C E
M A N U A L
S u p p l e m e n t
STROKE
MFS
A
- ｜
OB No.
-
-
NB

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Summary of Contents for TOHATSU MFS 60A

  • Page 1 S E R V I C E M A N U A L S u p p l e m e n t STROKE - ｜ OB No.

  • Page 3: Table Of Contents

    Introduction This manual has been prepared as a supplement for the MFS60A. Please utilize this manual together with the service manual of our outboard motors MFS40A/MFS50A. Contents 2) Ignition and Combustion Orders ..... 4-4 1. Service Information 1. Tools and Instruments ....3) Ignition Timing ........
  • Page 4 6) Inspection of Timing Belt .......5-22 28) Inspection of Cylinder Inner Diameter ...5-42 7) Installation of Pulley and Timing Belt ..5-23 29) Inspection of Piston Clearance ....5-42 8) Removing Cylinder Head ......5-24 30) Inspection of Piston Ring Side Clearance 5-43 9) Inspection of Valve Spring ......

  • Page 5: Service Information

    Service Information 1. Tools and Instruments ....................1) Test Propeller ............................1-2 2) Measuring instruments ..........................1-2...

  • Page 6: Tools And Instruments

    Service Information 1. Tools and Instruments 1) Test Propeller P/N. 3UR-64110-0 Outer diameter : 236 mm Width : 22.5 mm Rotational speed at WOT Outboard motor model (Wide Open Throttle) (r/min) MFS60A 5000 - 6000 2) Measuring instruments 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...

  • Page 7: Service Data

    Service Data 1. Specifications ........................2-2 2. Maintenance Data ........................2-6 3. Tightening Torque Data ......................2-14...

  • Page 8: Specifications

    Service Data 1. Specifications Model MFS60A Item Unit (with Remote Control) (with Multi Tiller Handle) Dimensions (approx.) Overall Length mm (in) with Remote Control : 783 (30.8) with Multi Tiller Handle : 1,382 (54.4) Overall Width mm (in) 404 (15.9) mm (in) 1,257 (49.5) Overall Height...
  • Page 9 Model MFS60A Item Unit (with Remote Control) (with Multi Tiller Handle) Fuel & Oil Type of Fuel Unleaded Gasoline (Research Octane Number 90 or over, Pump posted Octane Number 87 or over) Fuel Tank Capacity Fuel Priming System ECU (Electronic Control Unit) Fuel Pumping System Mechanical (Plunger) pump + Electric System Type...
  • Page 10 Service Data Model MFS60A Item Unit (with Remote Control) (with Multi Tiller Handle) Warning System Over-revolution Controls engine speed to approximately 6,200 r/min or Protection less (High Speed ESG). Warning buzzer sounds. Engine Hydraulic Controls engine speed to approximately 2,800 r/min or Pressure Low less (Low Speed ESG).
  • Page 11 4st 60 2019...

  • Page 12: Maintenance Data

    Service Data 2. Maintenance Data Parts Name Item Standard Value Cylinder Head Build up of carbon in combustion chamber Measure the cam journal clearance 42.000 to 42.025 mm (1.65354 to 1.65453 in) Distortion or damage on mating surface Distortion Amount : 0.05 mm (0.0020 in) or less Corrosion on the mating surface Cooling water passage clogged Cylinder...
  • Page 13 Functional Limit Action To Be taken Clean to remove. 42.050 mm (1.65551 in) Replace if more than specified limit. 0.1 mm (0.004 in) 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.
  • Page 14 Service Data Parts Name Item Standard Value Intake Valve Valve Clearance IN 0.20 to 0.25 mm (0.008 to 0.010 in) Exhaust Valve EX 0.30 to 0.35 mm (0.012 to 0.014 in) Valve Stem Outer Diameter IN 5.48 mm (0.2157 in) EX 5.46 mm (0.2150 in) Valve Guide Inner Diameter IN 5.51 mm (0.2169 in)
  • Page 15 Functional Limit Action To Be taken Adjust into specified range. 5.46 mm (0.2150 in) Replace if less than specified limit. 5.44 mm (0.2142 in) 5.55 mm (0.2185 in) Replace if more than specified limit. 5.57 mm (0.2193 in) 0.070 mm (0.00276 in) Replace if more than specified limit.
  • Page 16 Service Data Parts Name Item Standard Value Magneto Ignition Timing (at 850 r/min) ATDC 5°±5° Spark Performance (at 500 r/min) 10 mm (0.4 in) or over (Use genuine spark tester.) Alternator Output (at 4,000 r/min) 12 V 252 W Alternator Resistance Between Yellow and Yellow (at 20°C) 0.28 to 0.42Ω...
  • Page 17 Functional Limit Action To Be taken 10 mm (0.4 in) Replace if less than specified value. Replace if out of specified range. Replace if out of specified range. Adjust to specified range. Replace if out of specified range. Replace if out of specified range. Clean to remove carbon build up and dirt.
  • Page 18 Service Data Parts Name Item Standard Value Thermostat Valve Operation Starting Temperature (Submerged) 60°C ± 1.5°C (140 ± 3°F) Valve Full Open Temperature (Submerged) 75°C (167°F) Valve Full Open Lift (Submerged) 3.0 mm (0.12 in) or more Pump Impeller Wear, Crack Pump Case (Liner) Wear Guide Plate...
  • Page 19 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. 3.0 mm (0.12 in) Replace if less than specified limit. Wear, crack or damage on tips and upper and lower surface lips Replace pump case liner and guide plate as a set.

  • Page 20: Tightening Torque Data

    Service Data 3. Tightening Torque Data Tightening Torque N•m Type of Fastened Components Wrench A Screw B x Pitch Fastener N•m lb•ft kg•m 1 First Tightening Torque : Engine M10 x 1.25 Bolt 2 Final Tightening Torque : Cylinder Head (Cylinder Block and Cylinder Head) 1 First Tightening Torque : M8 x 1.25...
  • Page 21 Tightening Torque N•m Type of Fastened Components Wrench A Screw B x Pitch Fastener N•m lb•ft kg•m Gear Case Pinion Gear (B Gear) M12 x 1.0 Propeller M16 x 1.5 Top Cowl Tilt Handle M6 x 1.0 Nylon Nut Tightening Torque N•m Type of Fastened Components Wrench A...
  • Page 22 Service Data 2-16 4st 60 2019...

  • Page 23: Maintenance

    Maintenance 1. Inspection Schedule ....................2. Inspection Items ....................... 1) Inspection and Adjustment of Valve Clearance ..................3-3 2) Inspection of Idle Speed .......................... 3-4 3) Inspection of Ignition Timing ........................3-4...

  • Page 24: Inspection Schedule

    Maintenance 1. Inspection Schedule Inspection intervals Description Inspection procedure Remarks First 20 Every 50 Every 100 Every 200 hours of 1 hours of 3 hours of 6 hours of 1 month months months year Check and clean or Replace Fuel filter if necessary.
  • Page 25 2. Inspection Items 1) Inspection and Adjustment of Valve Clearance • Perform inspection and adjustment of valve clearances when engine is cold. • No.1 piston is to be at top dead center of compression stroke(make sure both valves are closed). Mark Remove flywheel cover, spark plug, cylinder head cover, ignition coil connector and harness.

  • Page 26: Inspection Of Idle Speed

    Maintenance 2) Inspection of Idle Speed Start engine and run for 5 minutes to warm up. Check idle speed to use tachometer or diagnostic program. Tachometer : P/N. 3GF-72647-1 Idle Speed : 850-± 30 r/min 3) Inspection of Ignition Timing Adjusting system : Automatic control, requiring no manual adjustment.

  • Page 27: Fuel System (Fuel Injection)

    Fuel System (Fuel Injection) 1. Piping Arrangement Diagram ………… 1) Ignition Timing Controls ……………………… 4-4 Fuel Hose, Vent Hose, Breather Hose, 2) Ignition and Combustion Orders ………… 4-4 Cooling Water Hose ……………………………… 4-2 3) Ignition Timing …………………………………… 4-4 2. Ignition System ………………………… 4) Operations …………………………………………...

  • Page 28: Piping Arrangement Diagram

    Fuel System (Fuel Injection) 1. Piping Arrangement Diagram Fuel Hose, Vent Hose, Breather Hose, Cooling Water Hose Rear Section Port Side Ref. Description 1 Fuel Hose (Fuel Connector to Fuel Filter) 2 Fuel Hose (Fuel Filter to Fuel Pump) 3 Fuel Hose (Fuel Pump to Vapor Separator) 4 Breather Hose (Cylinder Head to Intake Silencer 5 Cooling Water Hose (Engine Base to Fuel Cooler) 6 Cooling Water Hose (Fuel Cooler to Cooling Water Check Port)

  • Page 29: Ignition System

    2. Ignition System For ignition system, battery 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 started, electric current is generated in the alternator and to charge the battery. Which is input to ECU's regulator to feed power needed for operations of ignition coil, fuel injector and fuel feed pump (FFP).

  • Page 30: Ignition Timing Controls

    Fuel System (Fuel Injection) (2) Ignition Control 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 31 (3) Fuel Feed System Fuel pump 3 (low pressure mechanical type) draws fuel from fuel tank, and feed it to fuel feed pump 5 (FFP) located in the vapor separator 4 through fuel connector 1 and fuel filter 2. Highly pressurized fuel, fed into fuel rail 7 and fuel injector, and then, injected into intake manifold. Excessive fuel that is not used by fuel injector passes through fuel regulator 6, and circulated in the vapor separator 4 to keep fuel pressure constant.
  • Page 32 Fuel System (Fuel Injection) 4st 60 2019...

  • Page 33: Power Unit

    Power Unit 18) Installation of Valves …………………………… 5-36 1. Parts Layout ……………………………… Engine ……………………………………………………… 5-2 19) Installation of Cam Shaft……………………… 5-37 Magneto …………………………………………………… 5-3 20) Installation of Rocker Arm Shaft ………… 5-38 Electric Parts …………………………………………… 5-4 21) Installation of Oil Pump ……………………… 5-38 Fuel system ………………………………………………...

  • Page 34: Parts Layout

    Power Unit 1. Parts Layout Engine 1 15 N·m (11 lb·ft) [1.5 kgf·m] 2 30 N·m (22 lb·ft) [3.0 kgf·m] Ref. Description Q'ty Remarks Power Unit 2 Engine Base Gasket Do not reuse. 3 Dowel Pin 4 Bolt 8 M8 L=115mm 5 Tapping Screw 6 Bolt M6 L=16mm...

  • Page 35: Magneto

    Magneto P/L Fig. 7 150 N·m (110 lb·ft) [15.0 kgf·m] å ∫ Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty Flywheel W/Gear 15 Bolt 6 M6 L=25mm 2 Alternator Ass'y 16 Dowel Pin 6-12 2 Cylinder Blok-Coil Braket 3 Key 19-7-5 17 Pulsar Coil 4 Nut 20-p1.25 18 Pulsar Coil Guard...

  • Page 36: Electric Parts

    Power Unit Electric Parts P/L Fig. 9 8 N·m (6 lb·ft) [0.8 kgf·m] 1327 1327 ç å ∫ å ç ∫ 1327 1327 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty Oil Pressure Switch 12 Spring Washer 2 Engine Temp Sensor 13 Terminal Cap 8-13-28 Red for Gas Assist Model 3 Bracket...
  • Page 37 P/L Fig. 9 8 N·m (6 lb·ft) [0.8 kgf·m] 1327 1327 ç å ∫ å ç ∫ 1327 1327 Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 20 Terminal Cap 8-13-28 6 Red for PTT Model 29 Band 203 Do not reuse. 21 Cord Ass'y 30 Terminal Cap 8-13-28 2 Black for PTT Model...

  • Page 38: Fuel System

    Power Unit Fuel system P/L Fig. 6 Fig.5-1 Fig.5-6 Fig.5-1 Fig.1 CYLINDER Fig.1 CYLINDER EXPOSURE Fig.16-19 4st OIL Fig.15-16 4st OIL Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks Rubber Mount 12 Bolt 2 M6 L=25mm 2 Washer 3 M8 Intake Manifold 13 Dowel Pin 6-16 Vapor Separator Assy...
  • Page 39 P/L Fig. 6 Fig.5-1 Fig.5-6 Fig.5-1 Fig.1 CYLINDER Fig.1 CYLINDER EXPOSURE Fig.16-19 4st OIL Fig.15-16 4st OIL Ref. Description Remarks Q'ty 22 Clip ø9.4 23 Fuel Filter Ass'y 24 Cup 25 O-ring Do not reuse. 26 Filter 27 Float 28 O-ring Do not reuse.

  • Page 40: Vapor Separator

    Power Unit Vapor Separator Ref. Ref. Description Remarks Description Remarks Q'ty Q'ty 16 Vapor Separator Ass'y 25 Grommet F.F.P . Lower Lower 17 Float 26 Filter (inlet) 27 Fuel Regulator 18 Float Arm Pin 28 Holder 19 Float Valve Ass'y (W/valve pin) 29 O-Ring 20 Fuel Feed Pump Upper...
  • Page 41 4st 60 2019...
  • Page 42 Power Unit P/L Fig. 5 Intake Manifold P/L Fig. 5 Fig.6-11 Fig.6-9 Fig.6-12 Fig.6-12 32 31 Fig.6-13 Fig.6-10 Fig.6 Fig.3-50 5-10 4st 60 2019...

  • Page 43: Intake Manifold

    Ref. Description Q'ty Remarks Intake Manifold Isc Valve Idle Speed Control Valve Bolt M6 L=20mm MAP Sensor Manifold Air Temperature & Pressure Bolt M6 L=20mm Fuel Rail Ass'y Fuel Injector Ass'y Bolt M6 L=20mm Throttle Body Ass'y ø45 Gasket Do not reuse. Bolt M6 L=20mm Intake Silencer Ass'y...

  • Page 44: Pulley • Timing Belt

    Power Unit Pulley • Timing Belt P/L Fig. 4 27 N·m (20 lb·ft) [2.7 kgf·m] 120 N·m (88 lb·ft) [12.0 kgf·m] 1342 1342 1342 1342 Ref. Description Q'ty Remarks Drive Pulley Timing Pulley 2 Key t=4 Crankshaft 3 Belt Guide 4 Nut 39-p1.5 5 Driven Pulley Camshaft Pulley...

  • Page 45: Cylinder Head & Oil Pump

    Cylinder Head & Oil Pump P/L Fig. 3 1 30 N·m (22 lb·ft) [3.0 kgf·m] 2 60 N·m (44 lb·ft) [6.0 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 1 15 N·m (11 lb·ft) [1.5 kgf·m] 2 30 N·m (22 lb·ft) [3.0 kgf·m] 4st OIL 7 N·m (5 lb·ft) [0.7 kgf·m] 4st OIL...
  • Page 46 Power Unit P/L Fig. 3 1 30 N·m (22 lb·ft) [3.0 kgf·m] 2 60 N·m (44 lb·ft) [6.0 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 1 15 N·m (11 lb·ft) [1.5 kgf·m] 2 30 N·m (22 lb·ft) [3.0 kgf·m] 4st OIL 7 N·m (5 lb·ft) [0.7 kgf·m] 4st OIL 4st OIL...

  • Page 47: Cylinder • Crankcase

    Cylinder • Crankcase P/L Fig. 1 Fig.3-52 Fig.15-30 1342 1342 30 N·m (22 lb·ft) [3.0 kgf·m] 4st OIL 1 12 N·m (9 lb·ft) [1.2 kgf·m] 2 24 N·m (18 lb·ft) [2.4 kgf·m] 1 6 N·m (4.5 lb·ft) [0.6 kgf·m] 2 11.5 N·m (8.5 lb·ft) [1.15 kgf·m] 18 N·m (13 lb·ft) [1.8 kgf·m] 4st OIL 3/4 rotating (270˚)

  • Page 48: Piston & Crankshaft

    Power Unit Piston & Crankshaft P/L Fig. 2 4st OIL mark 4st OIL 1 15 N·m (11 lb·ft) [1.5 kgf·m] 2 30 N·m (22 lb·ft) [3.0 kgf·m] mark 4st OIL 4st OIL Ref. Ref. Description Q'ty Remarks Description Q'ty Remarks Crankshaft A'ssy 9-1 Piston 2-1 Plain Shaft Bearing (Brown)

  • Page 49: Top Cowl

    Top Cowl P/L Fig. 18 2 N·m (1.4 lb·ft) [0.2 kgf·m] Ref. Description Remarks Q'ty Caution Decal (A) 2 Top Cowl Assy (Service) 3 Top Cowl Sub-Ass'y 4 Top Cowl Seal 5 Tilt Handle Gray 6 Nylon Nut 6-p1.0 7 Washer 6-16-1.5 8 Decal Set 9 Front Decal 5-17...

  • Page 50: Inspection Items

    Power Unit 2. Inspection Items 1) Inspection of Compression Pressure Refer to "Inspection of Compression Pressure" in chapter 3. Compression Pressure (Reference) : 1.5 MPa (218 PSI) [ 15.3 kgf/cm ] ±10 % 2) Inspection of Oil Pressure Spread rag below oil pressure switch. Remove oil pressure switch and connect oil pressure gauge 1 to switch hole.
  • Page 51 Disconnect battery cables 1. Open the cable terminal holder cover 2 and disconnect connecters 3 (3). Remove the electrical box cover and disconnect PTT motor leads 4 and PTT switch coupler 5. Disconnect neutral switch leads (green) 6. Remove the pins 7 and then remove the cable joints. 5-19 4st 60 2019...
  • Page 52 Power Unit Disconnect the fuel hose 8 and flushing hose 9 . Remove oil level gauge 0. Disconnect cooling water (fuel cooler) hoses q. Remove tapping screws (L = 4 pieces. S = 3 pieces.) and bolt (one piece.), then remove apron. Remove power unit by removing bolts w (8) and then lifting it.
  • Page 53 Remove flywheel and key. å å Flywheel Holder : Commercially available item å Flywheel Puller : Use puller contained in the following puller kit. ∫ Flywheel Puller Kit : P/N. 3T1-72211-0 CAUTION Apply forces to tools toward directions as shown, and perform work taking care not to allow flywheel holder to remove.

  • Page 54: Removing Timing Belt And Pulley

    Power Unit 5) Removing Timing Belt and Pulley Turn timing pulley 1 clockwise to bring " " mark a of timing pulley to " " mark b of cylinder block, and check that " I" mark c of cam shaft pulley 2 and " " mark d of cylinder head are aligned with each other.

  • Page 55: Installation Of Pulley And Timing Belt

    7) Installation of Pulley and Timing Belt Check that " " mark a of timing pulley 1 and " " mark b of cylinder block are aligned with each other. No.1 piston is to be at top dead center of compression stroke.

  • Page 56: Removing Cylinder Head

    Power Unit Turn timing pulley 5 clockwise twice, and check that locating marks a and b , and c and d of pulleys 5 and 6 are aligned with each other respectively. 8) Removing Cylinder Head • No.1 piston is to be at top dead center of compression stroke.
  • Page 57 Remove fuel system parts and intake manifold ass'y. Remove electrical system parts from power unit. 5-25 4st 60 2019...
  • Page 58 Power Unit Remove camshaft pulley, cylinder head cover and hose. To remove, refer to the "Removing Timing Belt and Pulley" section in Chapter 5. Remove cylinder head bolts in the reverse sequence of order shown, and remove cylinder head. CAUTION Do not scratch or give damage to mating surfaces of cylinder head and cylinder block.

  • Page 59: Inspection Of Valve Spring

    Compress valve spring 7 by using compressor 8, remove cotter 9, and then, spring and valve 0. Valves, springs and other related parts should be arranged in the order they are removed. Valve Spring Compressor 8 : Commercially available item 9) Inspection of Valve Spring Measure valve spring free length a.

  • Page 60: Inspection Of Valve

    Power Unit 10) Inspection of Valve Check valve for dent and wear on the face. Replace if necessary. Measure valve stem outer diameter a . Replace if the diameter is less than specified value. Valve Stem Outer Diameter a : Standard Value Intake Side : 5.48 mm (0.216 in) Exhaust Side : 5.46 mm (0.215 in) Functional Limit :...

  • Page 61: Inspection Of Valve Seat

    12) Inspection of Valve Seat 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 a that can be identified with red lead adhered to valve face.

  • Page 62: Correction Of Valve Seat

    Power Unit 13) Correction of Valve Seat Use valve seat cutter (commercially available item) to correct valve seat. 30˚ 45˚ 60˚ 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.
  • Page 63 Use 45 degree cutter to adjust contact width of valve seat c to specified value. 45˚ b Width before correction c Specified width Valve seat contact area is located on the center, which should be adjusted to specified value by cutting upper and 30˚...

  • Page 64: Rocker Arm Shaft

    Power Unit Apply thin coat of abrasive compound on the overall valve seat contact area, and turn valve lapper (commercially available item) while tapping valve. CAUTION Per form the work by taking care not to allow abrasive compound to adhere to valve stem and valve guide.

  • Page 65: Inspection Of Cam Shaft

    15) Inspection of Cam Shaft Measure cam height. Replace if the height is less than specified value. Cam Height at Both Intake and Exhaust Sides a : Standard Value 35.70 mm (1.4055 in) Functional Limit : Cam Height at Both Intake and Exhaust Sides a 35.34 mm (1.3913 in) Measure cam shaft runout.

  • Page 66: Inspection Of Cylinder Head

    Power Unit 16) Inspection of Cylinder Head Remove carbon build-up of combustion chamber, and check for deterioration. Use straight edge 1 and thickness gauge 2 to check distortion of cylinder head in the directions shown. Replace if the distortion is over specified value. Cylinder Head Distortion Amount : 0.05 mm (0.0020 in) or less Functional Limit :...

  • Page 67: Inspection Of Oil Pump

    17) Inspection of Oil Pump 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 a : 0.25 mm (0.0098 in ) Clearance between outer and inner rotors b : 0.16 mm (0.0063 in) Clearance between sides of rotor and body c :...

  • Page 68: Installation Of Valves

    Power Unit 18) Installation of Valves Install valve spring seat 1, and then apply oil to valve guide and attach new valve stem seal 2. 4st OIL Intake Side : Black Exhaust Side : Green Install valve 3, valve spring 4 and retainer 5 in the order shown, and then, attach valve spring compressor 6.

  • Page 69: Installation Of Cam Shaft

    19) Installation of Cam Shaft Apply engine oil to periphery of new oil seal 1 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. 1 Oil seal 50-68-9 Install cam shaft 2 from direction shown.

  • Page 70: Installation Of Rocker Arm Shaft

    Power Unit 20) Installation of Rocker Arm Shaft Install rocker arms 1, springs 2 and, washers 3 from lower side of cylinder head while installing rocker arm shaft. It is easy to assemble and kept together each rocker arm with tie wraps. Tighten rocker arm shaft locating bolts in two steps to specified torque.

  • Page 71: Installation Of Cylinder Head

    22) Installation of Cylinder Head No.1 piston is to be at top de ad center of compression stroke. " mark a of pulley After installing cam shaft pulley, bring " 1 to " " mark b of cylinder head. Check that " " mark c of belt guide and " " mark d of cylinder block are aligned with each other.

  • Page 72: Disassembly Of Cylinder Block

    Power Unit 23) Disassembly of Cylinder Block Remove thermostat cover bolt and the cover 1 and exhaust cover 2. Remove oil filter 3. Wipe off spilled 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.

  • Page 73: Removing Of Drive Pulley

    24) Removing of Drive Pulley Secure crankshaft holder 1 with vice, and then insert crankshaft. Crankshaft Holder 1 : P/N. 3KY-72815-0 It may help to heat the nut with a small torch to be able to remove easier. Also, many front wheel drive auto sockets work well for removal/ installation drive belt pulley nuts.

  • Page 74: Inspection Of Piston Outer Diameter

    Power Unit 27) Inspection of Piston Outer Diameter Measure piston outer diameter between points specified. Replace if the diameter is less than specified value. Piston Outer Diameter a : Standard Value 69.97 mm (2.7547 in) Measurement Points b : 9 mm (0.35 in) above piston skirt bottom Functional Limit : 69.90 mm (2.7520 in) 28) Inspection of Cylinder Inner Diameter...

  • Page 75: Inspection Of Piston Ring Side Clearance

    30) Inspection of Piston Ring Side Clearance Measure piston side clearance. Replace piston and piston rings as a set if the clearance is over specified value. Piston Side Clearance : Top Ring a : 0.04 to 0.08 mm (0.0016 to 0.0031 in) Second Ring b : 0.01 to 0.05 mm (0.0004 to 0.0020 in) Oil Ring c : 0.03 to 0.13 mm (0.0012 to 0.0051 in) Functional Limit :...

  • Page 76: Inspection Of Piston Pins

    Power Unit 32) Inspection of Piston Pins Measure piston pin outer diameter. Replace piston pin if outer diameter is less than specified value. Piston Pin Outer Diameter : Standard Value 17.00 mm (0.6693 in) Functional Limit : 16.970 mm (0.66811 in) Measure piston pin inner diameter a.

  • Page 77: Inspection Of Crankshaft

    35) Inspection of Crankshaft Measure crankshaft journal outer diameter a and crank pin outer diameter b. Replace crankshaft if either outer diameter is less than specified value. Crankshaft Journal Outer Diameter a : Standard Value 39.99 mm (1.5744 in) Crank Pin Outer Diameter b : Standard Value 37.99 mm (1.4957 in) Functional Limit : Crankshaft Journal Outer Diameter a :...

  • Page 78: Oil Clearance

    Power Unit 36) Inspection of Crank Pin (rod journal) Oil Clearance Clean connecting rod and metal bearing, and then install metal bearing. Place cylinder block upside down on the work bench. Install piston to connecting rod 1. Do not attach piston rings. Install crankshaft on the cylinder block.

  • Page 79: Inspection Of Crank Shaft Main Journal Oil Clearance

    37) Inspection of Crank Shaft Main Journal Oil Clearance 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 1 and crankshaft 2 to cylinder block 3. •...

  • Page 80: Selecting Of Cylinder/Crankcase Metal Bearing

    Power Unit 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 : 0.020 to 0.041 mm (0.00079 to 0.00161 in) Functional Limit : 0.060 mm (0.00236 in) If the clearance is less than specified value, check...

  • Page 81: Metal Bearing

    Check that matching chart of crank journal metal bearing code as shown below chart, and then select crank journal metal bearing. Code Brown Brown Black Brown Black Black Black Black Blue Crank journal metal bearing thickness Parts No. Color Thickness 1.996 to 2.000 mm 3KY-07707-0 Brown...

  • Page 82: Assembling Piston And Connecting Rod

    Power Unit Connecting rod metal bearing thickness Parts No. Color Thickness 1.491 to 1.495 mm 3KY-00080-0 Brown (0.05870 to 0.05886 in) 1.495 to 1.500 mm 3KY-00081-0 Black (0.05886 to 0.05906 in) 1.500 to 1.505 mm 3KY-00082-0 Blue (0.05906 to 0.05925 in) 40) Assembling Piston and Connecting Rod Install connecting rod 2, piston pin 3, and piston pin clips 4 to piston 1.
  • Page 83 Put pistons into cylinder with piston 1 "UP" mark directing flywheel side and piston slider 6 set on the pistons. Before installing, apply engine oil to piston peripheral surfaces, piston rings and piston sliders. Piston Slider 6 : P/N. 3KY-72871-0 Clean and remove grease on bearing holder of crank case (x).
  • Page 84 Power Unit 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. • Remove grease from surface of crankcase and outside of bearing half. Apply 4 stroke engine oil to bearings.
  • Page 85 Install oil filter and tighten it to specified torque by using oil filter wrench. Apply thin coat of engine oil to O-ring before 4st OIL 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, thermostat cover r and exhaust cover t.

  • Page 86: Installation Of Power Unit

    Power Unit 41) Installation of Power Unit Clean power unit mating surface, and install dowel pin 1 and gasket 2. Install power unit 3, and tighten bolts 4 in two or three steps to specified torque. Power Unit Installation Bolt : First Tightening Torque : 15 N·m (11 lb·ft) [1.5 kgf·m ] Final Tightening Torque : 30 N·m (22 lb·ft) [ 3.0 kgf·m ] Install apron 5.
  • Page 87 Install PTT switch coupler 0 and PTT motor leads q. Positive Battery Cable Nut : 4 N·m (3 lb·ft) [ 0.4 kgf·m ] PTT Motor Lead Bolt : 4 N·m (3 lb·ft) [ 0.4 kgf·m ] Reconnect couplers w (3 pices), and then place them into cable terminal holder e and install holder cover.
  • Page 88 Power Unit 5-56 4st 60 2019...
  • Page 89 Copyright © 2019 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 90 S E R V I C E M A N U A L S u p p l e m e n t STROKE 5-4, Azusawa 3-Chome, Itabashi-Ku Tokyo 174-0051, Japan Tel: +81-3-3966-3117 Fax: +81-3-3966-0090 OB No.003-21073-0 1903NB www.tohatsu.com Printed in Japan...

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