TOHATSU MFS 4 Service Manual

4st 4/5/6 2011
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1.Service Information
1. Identification (Engine Serial Number) … 1-2
2. Work Safety ……………………………………… 1-2
1) Fire Prevention ……………………………………… 1-2
2) Ventilation …………………………………………… 1-2
3) Protection …………………………………………… 1-2
4) Genuine Parts ……………………………………… 1-2
5) Tools …………………………………………………1-3
6) Recommendations on Service …………………… 1-3
7) Cautions in Disassembling and
Assembling Components ………………………… 1-4
3. Tools and Instruments ……………………… 1-5
1) Test Propeller ……………………………………… 1-5
2) Instruments ………………………………………… 1-5
3) Special Tools………………………………………… 1-6
4. Pre-delivery Inspection …………………… 1-8
1) Steering Handle …………………………………… 1-8
2) Gear Shift …………………………………………… 1-8
3) Engine Oil …………………………………………… 1-8
4) Gear Oil ……………………………………………… 1-8
5) Fuel Tank Line ……………………………………… 1-9
6) Rigging ……………………………………………… 1-9
7) Inspection of Tilt Stoppe …………………………… 1-9
8) Inspection of Stop Switch ………………………… 1-9
9) Cooling Water Check Port ……………………… 1-10
10) Idle Operation ……………………………………… 1-10
11) Propeller Selection ………………………………… 1-11
12) Inspection of Forward and Reverse Shifts ……… 1-11
13) Trim Tab …………………………………………… 1-12
5. Break-in Operation…………………………… 1-12
6. Test Run …………………………………………… 1-12
7. Check After Test Run ……………………… 1-13
2.Service Data
1. Outline Dimensions …………………………… 2-2
1) Engine Dimensions ………………………………… 2-2
2) Clamp Dimensions ………………………………… 2-4
2. Engine Lubrication System Diagram …2-5
3. Cooling Water System Diagram ……… 2-6
4. Specifications …………………………………… 2-8
5. Maintenance Data …………………………… 2-10
6. Tightening Torque Specifications ………… 2-14
7. Sealant and Lubricant …………………… 2-15
3.Maintenance
1. Special Tools……………………………………… 3-2
2. Inspection Schedule ………………………… 3-3
3. Inspection Items ……………………………… 3-4
1) Inspection of Top Cowl …………………………… 3-4
2) Fuel System ………………………………………… 3-4
3) Inspection of Fuel Tank …………………………… 3-5
4) Inspection of Fuel Filter …………………………… 3-5
5) Replacement of Engine Oil ………………………… 3-6
6) Inspection of Gear Oil Quantity …………………… 3-7
7) Inspection of Water Pump ………………………… 3-7
8) Replacement of Gear Oil ………………………… 3-9
9)
Inspection of Gear Case (for leakage) …………… 3-10
10) Inspection of Spark Plugs ………………………… 3-11
11) Inspection of Compression Pressure …………… 3-12
12) Inspection and Adjustment of Valve Clearance… 3-13
13) Throttle Cable ……………………………………… 3-15
14) Inspection of Idle Engine Speed ………………… 3-17
15) Inspection of Ignition Timing……………………… 3-17
16) Inspection of Anode ……………………………… 3-18
17) Replacement of Anode …………………………… 3-18
18) Inspection of Propeller …………………………… 3-19
19) Inspection of Thermostat ………………………… 3-19
20) Inspection of Cooling Water Passage…………… 3-20
21) Flushing with Water ……………………………… 3-21
22) Greasing Points …………………………………… 3-22
4.Fuel System
1. Special Tools …………………………………… 4-2
2. Parts Layout ……………………………………… 4-4
Carburetor & Fuel Pump ………………………………… 4-4
Integral Fuel Tank ……………………………………… 4-6
3. Carburetor Inner Passages ……………… 4-8
1) Idling Passage ……………………………………… 4-8
2) Off-Idle Passage …………………………………… 4-9
3) High Speed Passage ……………………………… 4-10
4) Choking Passage ………………………………… 4-11
4. Inspection Items ……………………………… 4-12
1) Inspection of Fuel Feed System Piping ………… 4-12
2) Draining Fuel ……………………………………… 4-12
3) Inspection of Fuel Tank and Fuel Tank Cap …… 4-13
4) Inspection of Fuel Cock…………………………… 4-13
5) Inspection of Fuel Filter …………………………… 4-13
6) Removing Carburetor …………………………… 4-14
7) Disassembling Carburetor ……………………… 4-16
8) Inspection and clean of Carburetor ……………… 4-17
9) Inspection of Fuel Connector …………………… 4-18
10) Assembling of Carburetor ……………………… 4-18
11) Adjustment of Float Height ……………………… 4-19
12) Installing Carburetor ……………………………… 4-19
13) Removing Fuel Pump …………………………… 4-20
14) Disassembly and Inspection of Fuel Pump …… 4-20
15) Assembly of Fuel Pump ………………………… 4-21
5.Power Unit
1. Special tools ……………………………………… 5-2
2. Parts Layout ……………………………………… 5-3
Engine …………………………………………………… 5-3
Magneto…………………………………………………… 5-4
Cylinder & Oil Pan ……………………………………… 5-6
Cylinder Head & Valve & Cam Shaft ………………… 5-8
Piston & Crank Shaft …………………………………… 5-10
Recoil Starter …………………………………………… 5-11
Top Cowl ………………………………………………… 5-12
3. Inspection Items ……………………………… 5-13
1) Inspection of Compression Pressure …………… 5-13
2) Inspection of Valve Clearance …………………… 5-14
3) Removing Power Unit …………………………… 5-16
4)
Removal and Disassembly of Crank Case Head … 5-17
5) Inspection of Crank Case Head ………………… 5-18
6) Assembly of Crank Case Head ………………… 5-18
7) Installation of Crank Case Head ………………… 5-18
8) Disassembly of Power Unit ……………………… 5-19
9) Removal of Rocker Arm ………………………… 5-22
10) Removing Cylinder Head ………………………… 5-23
11) Inspection of Rocker Arm and Pivot …………… 5-23
12) Inspection of Push Rod Plate …………………… 5-23
13) Inspection of Push Rod …………………………… 5-23
14)
Disassembly and Inspection of Oil Feed Pump …… 5-23
15) Disassembly of Cylinder and oil pan …………… 5-26
16)
Disassembly and Inspection of Breather Chamber
… 5-28
17) Inspection of Lifter………………………………… 5-28
18) Inspection of Cam Shaft ………………………… 5-29
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TOHATSU MFS 4 Specifications

General

Brand	TOHATSU
Model	MFS 4
Category	Outboard Motor
Language	English