TOHATSU MFS 4 Service Manual

4st 4/5/6 2011
vi
19) Inspection of Piston Outer Diameter …………… 5-30
20) Inspection of Cylinder Inner Diameter…………… 5-30
21) Inspection of Piston Clearance ………………… 5-30
22) Inspection of Piston Ring Side Clearance ……… 5-31
23) Inspection of Piston Rings ……………………… 5-31
24) Inspection of Piston Pin…………………………… 5-32
25) Inspection Connecting Rod Small End
Inner Diameter …………………………………… 5-32
26) Inspection of Connecting Rod Big End
Inner Diameter …………………………………… 5-32
27) Inspection of Connecting Rod Big End
Side Clearance …………………………………… 5-33
28) Inspection of Crank Shaft …………………………5-33
29) Disassembly and Inspection of Oil Pan ………… 5-34
30) Removal of Valves and Springs ………………… 5-35
31) Inspection of Valve Springs ……………………… 5-35
32) Inspection of Valve………………………………… 5-36
33) Inspection of Valve Guide ………………………… 5-36
34) Inspection of Valve Seat ………………………… 5-37
35) Correction of Valve Seat ………………………… 5-38
36) Installation of Valves ……………………………… 5-41
37) Installation of Piston and Connecting Rod ……… 5-42
38) Assembly of Cylinder Oil Pan …………………… 5-43
39) Installation of Cylinder Head……………………… 5-45
40) Installing Flywheel ………………………………… 5-47
41) Installation of Power Unit ………………………… 5-50
6.Lower Unit
1. Special Tools……………………………………… 6-2
2. Parts Layout ……………………………………… 6-3
Drive Shaft Housing……………………………………… 6-4
3. Inspection Items ……………………………… 6-8
1) Draining Gear Oil …………………………………… 6-8
2) Removing Propeller ………………………………… 6-8
3) Removing Lower Unit ……………………………… 6-9
4) Disassembly of Water Pump ……………………… 6-9
5) Inspection of Water Pump………………………… 6-10
6) Removing Propeller Shaft Housing Ass'y ……… 6-11
7) Disassembly of Propeller Shaft Housing ……… 6-12
8) Inspection of Propeller Shaft Housing…………… 6-12
9) Assembly of Propeller Shaft Housing …………… 6-13
10) Removing Drive Shaft …………………………… 6-13
11) Disassembly of Propeller Shaft Ass'y …………… 6-14
12) Inspection of Propeller Shaft …………………… 6-14
13) Assembly of Propeller Shaft Ass'y ……………… 6-14
14) Removing Clutch Cam and Cam Rod…………… 6-15
15) Disassembly of Clutch Cam and Cam Rod …… 6-15
16) Inspection of Clutch Cam and Cam Rod ……… 6-15
17) Assembly of Clutch Cam and Cam Rod ………… 6-16
18) Removing Pump Case (Lower) ………………… 6-16
19) Disassembly of Pump Case (Lower) …………… 6-16
20) Assembly of Pump Case (Lower) ……………… 6-16
21) Inspection of Drive Shaft ………………………… 6-17
22) Inspection of Pinion (B) Gear and
Forward (A) Gea…………………………………… 6-17
23) Disassembly of Gear Case ……………………… 6-18
24) Inspection of Gear Case ………………………… 6-19
25) Assembly of Gear Case ………………………… 6-19
26) Installation of Forward Gear and
Pinion Gear (A and B Gears) …………………… 6-20
27) Reassembly of Pump Case (Lower) …………… 6-20
28) Installation of Clutch Cam and Cam Rod ……… 6-20
29) Determination of forward (A) gear backlash …… 6-21
30) Installation of Water Pump ……………………… 6-23
31) Installation of Propeller Shaft Housing ………… 6-24
32) Filling with Gear Oil ……………………………… 6-25
33) Installation of Lower Unit ………………………… 6-25
7.Bracket
1. Parts Layout ……………………………………… 7-2
Bracket & Reverse Lock ………………………………… 7-2
Drive Shaft Housing & Shift …………………………… 7-4
Bottom Cowl & Tiller Handle …………………………… 7-6
Cowl ……………………………………………………… 7-8
2. Disassembling and Assembling
Procedure
…………………………………………… 7-9
1) Removal and inspection of drive shaft housing … 7-9
2)
Removal and inspection of clamp bracket ………… 7-11
3) IInstallation of clamp bracket and drive shaft … 7-12
4)
Removal, inspection and installation of water pipe … 7-14
5)
Remove, inspection and installation of tiller handle … 7-15
6) Adjustment of Throttle Cable …………………… 7-18
8.Electrical System
1. Special Tools……………………………………… 8-2
Magneto…………………………………………………… 8-3
2. Ignition System and Ignition
Control System
………………………………… 8-4
1) Inspection of Ignition Spark………………………… 8-4
2) Inspection of Plug Cap……………………………… 8-5
3) Inspection of Igniter ………………………………… 8-6
4) Inspection of Stop Switch ………………………… 8-7
5) Inspection of Oil Pressure Switch ………………… 8-7
6) Inspection of Rectifier ……………………………… 8-8
7) Inspection of Lighting Coil ………………………… 8-8
9.Troubleshooting
1. Troubleshooting List ………………………… 9-2
2. Power Unit ………………………………………… 9-3
1 Engine will not start or is a little hard to start.
(Recoil starter operates normally.)
…………………… 9-3
2 Engine starts but stalls soon. ………………………… 9-5
Fuel System ………………………………………… 9-5
Ignition System ……………………………………… 9-6
Intake • Compression Pressure …………………… 9-7
3 Idle engine speed will not stabilize. ………………… 9-8
4 Rough acceleration. …………………………………… 9-9
5 Gear shifting cannot be made normally.
…………… 9-10
10.Wiring Diagram
11.C Model
Service Information
1. Specification • Service Data ………… 11-2
2. Parts Layout …………………………………… 11-12
3. Difference item ……………………………… 11-30
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TOHATSU MFS 4 Specifications

General

Brand	TOHATSU
Model	MFS 4
Category	Outboard Motor
Language	English