Stihl MS 280 User Manual

Online version - not for reprint
1MS 270, MS 280
q
© 2002 Andreas Stihl AG & Co., Waiblingen
Contents
1 Introduction 3
2 Safety Precautions 4
3 Specifications 5
3.1 Engine 5
3.2 Fuel System 5
3.3 Ignition System 5
3.4 Chain Lubrication 5
3.5 Tightening Torques 6
4 Troubleshooting
Chart 8
4.1 Clutch, Chain Drive,
Chain Brake, Chain
Tensioner 8
4.2 Rewind Starter 10
4.3 Chain Lubrication 11
4.4 Ignition System 12
4.5 Carburetor 13
4.6 Engine 16
5 Clutch, Chain Drive,
Chain Brake and
Chain Tensioner 17
5.1 Clutch Drum/Chain
Sprocket 17
5.2 Replacing the Chain
Catcher 18
5.3 Clutch 18
5.4 Chain Brake 20
5.4.1 Checking Operation 20
5.4.2 Removing 21
5.4.3 Installing 23
5.5 Chain Brake with
QuickStop Super 25
5.5.1 Removing 25
5.5.2 Installing 26
5.5.3 Checking Play 28
5.5.4 Adjusting Play 29
5.5.5 Brake Cable 29
5.5.6 Checking Operation
of Coasting Brake 30
5.6 Brake Spring Anchor
Pin 30
5.7 Chain Tensioner 31
5.8 Bar Mounting Studs 32
6 Engine 33
6.1 Muffler/Spark
Arresting Screen 33
6.2 Leakage Test 33
6.2.1 Preparations 33
6.2.2 Pressure Test 34
6.2.3 Vacuum Test 35
6.3 Oil Seals 36
6.4 Shroud 37
6.5 Cylinder and Piston 38
6.5.1 Removing 38
6.5.2 Installing 39
6.6 Piston Rings 42
6.7 Crankcase 43
6.7.1 Crankshaft 43
6.8 Decompression Valve 44
7 Ignition System 44
7.1 Ignition Module 45
7.1.1 Ignition Timing 45
7.1.2 Removing and
Installing 45
7.1.3 Testing the Ignition
Coil 46
7.2 Spark Plug Boot 48
7.3 Flywheel 48
7.4 Short Circuit Wire/
Ground Wire 49
7.5 Stop Contact 50
7.6 Ignition System
Troubleshooting 51
8 Rewind Starter 54
8.1 General 54
8.2 Fan Cover 54
8.3 Pawls 54
8.4 Rope Rotor 55
8.5 Starter Rope 56
8.5.1 ElastoStart 57
8.5.2 Tensioning 57
8.6 Starter Rope Guide
Bush 58
8.7 Replacing the Rewind
Spring 59
9 AV Handle System 60
9.1 Handlebar 60
9.2 Replacing Annular
Buffers 61
9.2.1 Crankcase 61
9.2.2 Tank Housing 62
9.3 Spring 63
10 Master Control/
Handle System 64
10.1 Switch Shaft 64
10.2 Throttle Trigger/
Interlock Lever 65
10.2.1 Machines without
QuickStop Super 65
10.2.2 Machines with
QuickStop Super 66
11 Chain Lubrication 67
11.1 Pickup Body/
Suction Hose 67
11.2 Delivery Hose 68
11.3 Valve 69
11.4 Oil Pump 70
11.5 Fan Housing 70
12 Fuel System 71
12.1 Air Filter 71
12.2 Carburetor 72
12.2.1 Removing and
Installing 72
12.2.2 Leakage Test 73
12.3 Servicing the
Carburetor 73
12.3.1 Metering Diaphragm 73
12.3.2 Inlet Needle 74
12.3.3 Fixed Jet 75
12.3.4 Pump Diaphragm 76
12.3.5 Accelerator Pump 77
12.4 Adjusting 79
12.4.1 Standard Setting 80
12.5 Tank Vent 81
12.6 Pickup Body 82
12.7 Fuel Hose 82

Stihl MS 280 Specifications

General

Sound Pressure Level	101 dB(A)
Sound Power Level	113 dB(A)
Oil Capacity	0.20 l (6.8 oz)
Guide Bar Length	16 in
Chain Pitch	3/8"

Summary

2 Safety Precautions

3 Specifications

3.5 Tightening Torques

4 Troubleshooting Chart

4.1 Clutch, Chain Drive, Chain Brake, Chain Tensioner

Troubleshooting for clutch, chain drive, brake, and tensioner issues.

4.2 Rewind Starter

Troubleshooting guide for the rewind starter mechanism.

4.3 Chain Lubrication

Troubleshooting for potential faults in the chain lubrication system.

4.4 Ignition System

Troubleshooting for engine misfires and power loss due to ignition.

4.5 Carburetor

Troubleshooting for carburetor flooding, stalling, and poor acceleration.

4.6 Engine

Troubleshooting engine starting, power delivery, and overheating problems.

5 Clutch, Chain Drive, Chain Brake and Chain Tensioner

5.4 Chain Brake

5.4.1 Checking Operation

Method to check the efficiency and function of the chain brake.

5.4.2 Removing

5.4.3 Installing

5.5 Chain Brake with QuickStop Super

5.5.1 Removing

5.5.2 Installing

6 Engine

6.2 Leakage Test

Procedures for testing engine crankcase for leaks.

6.2.2 Pressure Test

Method for conducting a pressure test on the engine crankcase.

6.2.3 Vacuum Test

Method for conducting a vacuum test on the engine crankcase.

6.3 Oil Seals

6.5 Cylinder and Piston

6.5.1 Removing

Detailed steps for removing the cylinder and piston assembly.

6.5.2 Installing

Detailed steps for installing the cylinder and piston assembly.

6.7 Crankcase

6.7.1 Crankshaft

Procedures for removing, inspecting, and replacing the crankshaft.

7 Ignition System

7.1 Ignition Module

Information and procedures related to the ignition module.

7.1.2 Removing and Installing

Steps for removing and installing the ignition module.

7.1.3 Testing the Ignition Coil

How to test the ignition module using specialized testers.

7.6 Ignition System Troubleshooting

A flowchart for diagnosing ignition system problems.

8 Rewind Starter

9 AV Handle System

10 Master Control/ Handle System

10.2 Throttle Trigger/Interlock Lever

Procedures for the throttle trigger and interlock lever system.

11 Chain Lubrication

11.4 Oil Pump

Procedures for checking and replacing the oil pump.

12 Fuel System

12.2 Carburetor

Procedures related to the carburetor.

12.2.1 Removing and Installing

Steps for removing and reinstalling the carburetor.

12.2.2 Leakage Test

Method to test the carburetor for leaks.

12.3 Servicing the Carburetor

General procedures for servicing carburetor components.

12.4 Adjusting

Procedures for adjusting the carburetor settings.

12.4.1 Standard Setting