Stihl MS 231 User Manual

1MS 231, MS 231 C, MS 251, MS 251 C
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© ANDREAS STIHL AG & Co. KG, 2010
RA_737_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 11
3.4 Rewind Starter 12
3.5 Ignition System 14
3.6 Carburetor 15
3.7 Engine 18
4. Clutch 19
4.1 Clutch Drum 19
4.2 Clutch 19
5. Chain Brake 20
5.1 Checking Operation 20
5.2 Brake Band 20
5.3 Brake Lever 21
5.4 Brake Lever on
Machines with
QuickStop Super 24
5.4.1 Adjusting
the brake cable 26
5.4.2 Brake cable
Removing
and Installing 27
5.5 Chain Tensioner 29
5.5.1 Quick Chain
Tensioner 30
5.5.2 Chain Catcher 30
5.6 Bar Mounting Stud 31
6. Engine 32
6.1 Muffler 32
6.2 Leakage Test 33
6.2.1 Preparations 33
6.2.2 Vacuum Test 34
6.2.3 Pressure Test 34
6.3 Oil Seals 35
6.3.1 Ignition side 35
6.3.2 Clutch side 36
6.4 Shroud 36
6.5 Engine 37
6.6 Cylinder / Crankshaft 38
6.7 Bearings / Crankshaft 41
6.8 Piston 42
6.9 Piston Rings 44
7. Ignition System 45
7.1 Ignition Timing 45
7.2 Preseparator 45
7.3 Install new
ignition module 45
7.4 Testing the
Ignition Module 47
7.5 Spark Plug Boot /
Ignition Lead 48
7.6 Flywheel 49
7.7 Short Circuit Wire 50
7.7.1 Testing 50
7.7.2 Removing and
Installing 50
7.7.3 Ground Wire 53
7.7.4 Contact Spring 53
7.8 Ignition System
Troubleshooting 55
8. Rewind Starter 58
8.1 General 58
8.2 Fan housing 58
8.3 Pawls 59
8.4 ErgoStart 60
8.5 Rope Rotor 61
8.6 Starter Rope / Grip 61
8.7 Tensioning
the Rewind Spring 62
8.8 Replacing
the Rewind Spring 63
9. Servicing
the AV System 66
9.1 AV Spring on Oil Tank 66
9.2 AV Spring on
Fuel Tank 66
9.3 AV Spring on
Handlebar 67
9.3.1 Stop Buffers 68
9.3.2 Buffers on Filter Base 69
9.4 Handlebar 69
10. Control Levers 71
10.1 Master Control Lever 71
10.1.1 Removing and
Installing 71
10.2 Throttle Trigger/
Lockout Lever 72
10.3 Throttle Trigger/
Lockout Lever –
QuickStop Super 73
10.3.1 Switch Lever
QuickStop Super 74
10.3.2 Lockout Lever –
QuickStop Super 75
10.3.3 Choke Rod 76
10.3.4 Throttle Rod 76
11. Chain Lubrication 78
11.1 Pickup Body 78
11.2 Oil Suction Hose 78
11.3 Oil Pump 78
11.4 Valve 80
12. Fuel System 81
12.1 Air Filter 81
12.2 Baffle 81
12.3 Filter Base 81
12.4 Air Guide Shroud 83
12.4.1 Air Guide Shroud –
Models with
Manual Fuel Pump 85
12.5 Carburetor 88
12.5.1 Leakage Test 89
Contents
All manuals and user guides at all-guides.com

Stihl MS 231 Specifications

General

Brand	Stihl
Model	MS 231
Category	Chainsaw
Language	English