Power Unit - TOHATSU MD 70-90C2 Service Manual

1. Special tools .............................. 5-2
2. Parts Layout .............................. 5-3
Engine .......................................... 5-3
Magneto.......................................... 5-4
Electric Parts (ECU•Diagram) ............ 5-6
Electric Parts (Starter Motor) ............... 5-8
Air Chamber (Air Box) ........................ 5-9
Throttle .......................................... 5-10
Cylinder Crank Case ........................ 5-12
Piston & Crank Shaft ........................ 5-14
3. Inspection Items ........................ 5-15
1) Inspection of
Compression Pressure ...............5-15
2) Removing Power Unit ..................5-16
3) Removing Air Compressor .........5-19
4) Removing Flywheel .....................5-20
5) Removing Alternator ..................5-20
6) Removing Starter Motor ...............5-21
7) Removing Cord Ass'y ..................5-22
8) Removing Oil Pump.....................5-25
9) Removing Throttle Link ...............5-25
10) Inspection of Throttle Body............5-26
11) Removing Air Chamber ...............5-27
12) Removing Thermostat ..................5-28
13) Inspection of Thermostat ............5-29
14) Removing Fuel System ...............5-29
15) Removing Cylinder Head /
Head Cover ..............................5-29
16) Inspection of Cylinder Head .........5-30
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Power Unit

17) Removing Exhaust Cover ............5-31
18) Inspection of Exhaust Cover .........5-32
19) Removing Crank Case ...............5-32
20) Removing Pistons .....................5-34
21) Disassembly of Crank Shaft .........5-35
22) Inspection of Crank Shaft ............5-35
23) Inspection of Cylinder ..................5-36
24) Inspection of Pistons ..................5-37
25) Assembly of Crank Shaft ............5-40
26) Installation of Pistons ..................5-41
27) Inspection of Crankcase ...............5-41
28) Assembly of Power Unit Parts ......5-42
29) Assembly of Crank Case Halves ...5-43
23) Installation of Exhaust Cover .........5-45
31) Installation of Cylinder Head .........5-46
32) Assembly of Crank Case Head ......5-47
33) Installation of Air Chamber ............5-48
34) Installation of Recirculation Hoses 5-50
35) Installation of Throttle Link ............5-50
36) Installation of Oil Pump ...............5-50
37) Installation of Fuel System ............5-51
38) Installation of Cord Ass'y and
Electrical Parts ...........................5-51
39) Installation of Starter Motor .........5-51
40) Installation of Alternator ...............5-51
41) Installation of Drive Pulley and
Flywheel....................................5-52
42) Installation of Air Compressor ......55-2
43) Installation of Power Unit ............5-52
5