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1
MS 311, MS 391
q
© ANDREAS STIHL AG & Co. KG, 2009
RA_542
_00_01_01
1.
Introduction and
Safety Precautions
3
1.1
Introduction
3
1.2
Safety Precautions
4
2.
Specifications
5
2.1
Engine
5
2.2
Fuel System
5
2.3
Ignition System
5
2.4
Chain Lubrication
5
2.5
Tightening Torques
6
3.
Troubleshooting
8
3.1
Clutch
8
3.2
Chain Drive,
Chain Brake,
Chain Tensioner
9
3.3
Chain Lubrication
10
3.4
Rewind Starter
11
3.5
Ignition System
12
3.6
Carburetor
13
3.7
Engine
16
4.
Clutch
17
4.1
Clutch Drum
19
5.
Chain Brake
20
5.1
Checking Operation
20
5.2
Brake Band
20
5.3
Brake Lever
22
5.4
Cam Lever
24
5.5
Pins
25
5.6
Chain Tensioner
25
5.7
Bar Mounting Studs
26
6.
Engine
27
6.1
Muffler
27
6.2
Leakage Test
28
6.2.1
Preparations
28
6.2.2
Vacuum Test
29
6.2.3
Pressure Test
29
6.3
Oil Seals
30
6.4
Shroud
31
6.5
Cylinder / Crankshaft 32
6.6
Bearings / Crankshaft 35
6.7
Piston
36
6.8
Piston Rings
38
6.9
Decompression Valve 38
7.
Ignition System
39
7.1
Ignition Timing
39
7.2
Preseparator
39
7.3
Ignition Module
39
7.4
Testing the
Ignition Module
41
7.5
Spark Plug Boot /
Ignition Lead
42
7.6
Flywheel
43
7.7
Short Circuit Wire
44
7.7.1
Testing
44
7.7.2
Removing and
Installing
44
7.7.3
Ground Wire
46
7.7.4
Contact Spring
46
7.8
Ignition System
Troubleshooting
48
8.
Rewind Starter
51
8.1
General
51
8.2
Fan housing
51
8.2.1
Segment
51
8.3
Pawls
51
8.4
Rope Rotor
52
8.5
Starter Rope / Grip
53
8.6
Tensioning the
Rewind Spring
54
8.7
Replacing the
Rewind Spring
55
9.
Servicing the
AV System
57
9.1
Buffer on Oil Tank
57
9.2
AV Spring on Oil Tank 57
9.3
AV Spring on
Fuel Tank
57
9.4
AV Spring on
Front Handle
58
9.5
Stop Buffer at
Clutch Side
59
9.6
Annular Buffer at
Ignition Side
59
9.7
Handlebar
59
10.
Control Levers
61
10.1
Master Control Lever 61
10.2
Throttle Trigger/Interlock
Lever
61
10.2.1 Choke Rod
63
10.2.2 Throttle Rod
64
11.
Chain Lubrication
65
11.1
Pickup Body
65
11.2
Oil Suction Hose
65
11.3
Oil Pump
66
11.4
Valve
67
Contents