TOHATSU MFS25 Service Manual page 6

5 Ignition System
(1) Configuration of Ignition System...
(2) Ignition Control ...........................
1) Ignition Timing Controls ........................ 4-21
2) Ignition and Combustion Orders ............ 4-21
3) Ignition Timing .................................... 4-21
4) Operations.......................................... 4-21
(3) Fuel Feed System ........................
6 Components of Fuel Feed System
1) Fuel Pump (Low Pressure Mechanical Pump) ... 4-23
2) Vapor Separator ................................. 4-23
3) Fuel Regulator .................................... 4-24
4) Fuel Cooler ....................................... 4-24
7 Outline of Fuel Injection System
1) Air Intake System ................................. 4-25
8 Inspection Items
1) Inspection of Fuel Supply System Piping... 4-26
2) Inspection of Filter .............................. 4-26
3) Inspection of Fuel Pump ........................ 4-28
4) Inspection of Fuel Connector .................. 4-28
5) Measuring fuel pressure ........................ 4-29
6) Inspection of Fuel Regulator .................. 4-30
7) Draining Fuel....................................... 4-31
8) Disassembly of Vapor Separator ............ 4-31
9) Inspection of Vapor Separator ............... 4-32
10) Reassembly of Vapor Separator ............ 4-33
11) Inspection of ISC (Idle Speed Control) ...... 4-33
12) Inspection of Idle Speed ........................ 4-33
5.Power Unit
1 Special Tools
2 Parts Layout
Engine ................................................... 5-3
Recoil Starter .......................................... 5-4
Magneto & ECU ....................................... 5-5
Electric Parts .......................................... 5-6
Fuel Pump, Fuel Rail, Vapor Separator ......... 5-8
Intake Manifold ....................................... 5-11
Cam Shaft & Oil Pump .............................. 5-12
Cylinder Head.......................................... 5-13
Intake Valve & Exhaust Valve ..................... 5-14
Cylinder ................................................ 5-15
Piston & Crankshaft ................................. 5-16
Top Cowl ................................................ 5-17
3 Inspection Items
1) Inspection of Compression Pressure......... 5-18
2) Inspection of Oil Pressure ..................... 5-19
3) Inspection of Valve Clearance ............... 5-20
4) Removing Power Unit ........................... 5-22
5) Removing Timing Belt and Pulley ............ 5-25
6) Inspection of Timing Belt ........................ 5-26
7) Installation of Pulley and Timing Belt......... 5-27
8) Removing Cylinder Head........................ 5-30
9) Inspection of Valve Spring ..................... 5-32
10) Inspection of Valve .............................. 5-33
11) Inspection of Valve Guide ..................... 5-33
12) Inspection of Valve Seat ........................ 5-34
13) Correction of Valve Seat ........................ 5-35
iv
.............................. 4-20
4-20
4-21
4-22
... 4-23
... 4-25
........................... 4-26
.................................... 5-2
.................................... 5-3
........................... 5-18
14) Inspection of Rocker Arm and Rocker Arm Shaft ... 5-37
15) Inspection of Cam Shaft .................. 5-38
16) Inspection of Cylinder Head ............... 5-39
17) Inspection of Oil Pump ..................... 5-40
18) Installation of Valves ........................ 5-41
19) Installation of Cam Shaft .................. 5-42
20) Installation of Rocker Arm Shaft ......... 5-42
21) Installation of Oil Pump ..................... 5-43
22) Installation of Cylinder Head............... 5-44
23) Disassembly of Cylinder Block............ 5-45
24) Inspection of Piston Outer Diameter ... 5-46
25) Inspection of Cylinder Inner Diameter... 5-46
26) Inspection of Piston Clearance ......... 5-46
27) Inspection of Piston Ring Side Clearance ... 5-47
28) Inspection of Piston Rings ............... 5-47
29) Inspection of Piston Pins .................. 5-48
30) Inspection of Connecting Rod Small End Inner Diameter ... 5-48
31) Inspection of Connecting Rod Big End Side Clearance ... 5-48
32) Inspection of Crankshaft .................. 5-49
33) Inspection of Crank Pin Oil Clearance ... 5-50
34) Inspection of Crank shaft Main Journal Oil Clearance ... 5-51
35) Inner Diameter of Cylinder/Crank Case Bearing Holder (Inner Diameter Code)... 5-52
36) Thickness of Bearing (Color of Inner Diameter Code) ... 5-52
37) Assembling Piston and Connecting Rod ... 5-53
38) Installation of Power Unit .................. 5-57
39) Removing Recoil Starter .................. 5-59
40) Disassembly of Recoil Starter ............ 5-59
41) Inspection of Recoil Starter ............... 5-60
42) Installation of Recoil Starter ............... 5-61
6.Lower Unit
1 Special Tools
.............................. 6-2
2 Parts Layout
................................. 6-4
Gear Case .......................................... 6-4
Drive System & Water Pump .................. 6-5
Shift ................................................ 6-7
3 Inspection Items
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... 6-10
7) Disassembly of Propeller Shaft Ass'y ... 6-11
8) Inspection of Propeller Shaft ............ 6-11
9) Assembly of Propeller Shaft Ass'y ...... 6-11
10) Disassembly of Propeller Shaft Housing ... 6-12
11) Inspection of Propeller Shaft Housing... 6-13
12) Assembly of Propeller Shaft Housing ... 6-14
13) Removing Pump Case (Lower) ......... 6-15
14) Disassembly of Pump Case (Lower) ... 6-15
15) Assembly of Pump Case (Lower) ...... 6-15
16) Removing Clutch Cam and Cam Rod... 6-15
17) Disassembly of Clutch Cam and Cam Rod... 6-15
18) Inspection of Cam Rod and Clutch Cam ... 6-16
........................ 6-8
25/30 2006