Stihl MS 240 User Manual

1MS 240, MS 260, MS 260 C
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© ANDREAS STIHL AG & Co. KG, 2013
RA_165_00_01_05
1. Introduction 3
2. Safety Precautions 5
3. Specifications 6
3.1 Engine 6
3.2 Fuel System 6
3.3 Ignition System 6
3.4 Chain Lubrication 6
3.5 Tightening Torquese 7
4. Troubleshooting 9
4.1 Clutch 9
4.2 Chain Drive,
Chain Brake,
Chain Tensioner 10
4.3 Chain Lubrication 11
4.4 Rewind Starter 12
4.5 Ignition System 13
4.6 Carburetor 15
4.7 Engine 18
5. Cutting Attachment 19
5.1 Chain Catcher 19
6. Clutch 20
6.1 Clutch Drum 22
7. Chain Brake 23
7.1 Checking Operation 23
7.2 Removing and Installing
the Brake Band 23
7.3 Brake Lever 25
7.4 Cam Lever 26
7.5 Pins 27
7.6 Side Chain Tensioner 28
7.6.1 Front Chain Tensioner 29
7.6.2 Quick Chain
Tensioner 29
7.7 Bar Mounting Studs 30
8. Engine 31
8.1 Muffler / Spark
Arresting Screen 31
8.2 Leakage Test 32
8.2.1 Preparations 33
8.2.2 Vacuum Test 34
8.2.3 Pressure Test 34
8.3 Oil Seals 35
8.4 Removing and
Installing the Shroud 36
8.5 Cylinder 37
8.6 Crankshaft 40
8.6.1 Removing and
Installing 40
8.6.2 Bearings / Crankcase 45
8.7 Piston 47
8.7.1 Removal 47
8.7.2 Installing 48
8.8 Piston Rings 49
8.9 Decompression Valve 50
9. Ignition System 51
9.1 Ignition Timing 51
9.2 Ignition Module 51
9.2.1 Removing and
Installing 51
9.3 Testing the
Ignition Module 54
9.4 Spark Plug Boot /
Ignition Lead 55
9.5 Flywheel 56
9.6 Short Circuit Wire 57
9.6.1 Testing 57
9.6.2 Removing and
Installing 57
9.6.3 Ground Wire 60
9.7 Ignition System
Troubleshooting 61
10. Rewind Starter 64
10.1 General 64
10.2 Removing and
Installing 64
10.3 Pawl 64
10.4 Rope Rotor 65
10.5 Starter Rope / Grip 66
10.6 Tensioning the Rewind
Spring 67
10.7 Replacing the Rewind
Spring 68
11. Servicing the
AV System 70
11.1 Annular Buffer on
Chain Catcher 70
11.2 Annular Buffer at
Clutch Side 70
11.3 Annular Buffer at
Ignition Side 71
11.4 Stop Buffer 72
11.5 Handlebar 72
11.6 Handlebar with
Handle Heating 73
12. Control Levers 76
12.1 Switch Shaft 76
12.1.1 Removing and
Installing 76
12.2 Throttle Trigger/Interlock
Lever 77
13. Chain Lubrication 80
13.1 Pickup Body 80
13.2 Oil Suction Hose 80
13.3 Oil Delivery Hose 81
13.4 Non-Adjustable
Oil Pump 81
13.5 Adjustable Oil Pump 82
13.6 Valve 83
14. Fuel System 85
14.1 Air Filter 85
14.2 Removing and Installing
the Carburetor 85
14.3 Leakage Test 86
14.4 Servicing the
Carburetor 87
14.4.1 Inlet Needle 89
14.4.2 Fixed Jet 89
14.4.3 Pump Diaphragm 90
14.4.4 Choke Shaft /
Choke Shutter 91
14.4.5 Adjusting Screws 91
14.5 Adjusting the
Carburetor 92
14.5.1 Basic Setting 92
14.5.2 Standard Setting 93
Contents

Stihl MS 240 Specifications

General

Chain pitch	3/8"
Oil Capacity	0.2 L
Guide bar length (recommended)	40 cm
Engine Power	2.0 kW (2.7 bhp)
Displacement	41.6 cm³