Stihl 029 039 Ms 290 310 390 Chain Tensioner

STIH)

STIHL MS 290, 310, 390

2004-11

Contents

1.

Introduction

2

2.

Safety Precautions

3

3.

Specifications

4

3.1 3.1.1 3.2 3.3 3.4 3.5

Engine Engine (USA only) Fuel System Ignition System Chain Lubrication Tightening Torques

4 4 5 5 5 6

6.5 6.5.1 6.5.2 6.6 6.7

30 31 33 35 35

7.

Ignition System

36

7.1 7.1.1 7.1.2

Ignition Module Ignition Timing Removing and Installing Testing the Ignition Module Spark Plug Boot Ignition Lead Flywheel Contact Spring Replacing Wiring Harness Ignition System Troubleshooting

37 37

7.1.3 4. 4.1 4.2 4.3 4.4 4.5 4.6 5.

5.1 5.2 5.3 5.4 5.5 5.6 5.6.1 5.6.2 5.7 5.7.1 5.7.2 5.8

Troubleshooting Chart Clutch, Chain Drive, Chain Brake, Chain Tensioner Rewind Starter Chain Lubrication Ignition System Carburetor Engine Clutch, Chain Drive, Chain Brake and Chain Tensioner Clutch Drum/Chain Sprocket Chain Catcher Spiked Bumper Collar Stud Clutch Chain Brake Checking Operation Removing and Installing Replacing Pins Removing Installing Chain Tensioner

6.

Engine

6.1

Muffler/Spark Arresting Screen Leakage Test Preparations Pressure Test Vacuum Test Oil Seals Shroud

6.2 6.2.1 6.2.2 6.2.3 6.3 6.4

7

7 8 9 10 11 13

14 14 15 15 16 16 18 18

7.2 7.2.1 7.3 7.4 7.5 7.6

23

43 45 48

8.1 8.2

General Removing and Installing Pawl Rope Rotor Starter Rope/Grip Tensioning Starter Rope Guide Bushing Replacing Rewind Spring

48

8.7

9.1 9.2 9.3 9.3.1 9.3.2 9.3.3

23 25 25 26 26 27 29

39 40 41 42 43

Rewind Starter

8.3 8.4 8.5 8.5.1 8.6

9.4 9.5

AV Handle System/ Handle Housing Front Handle Handle Housing Annular Buffers Front Handle/ Handle Housing Handle Housing/ Engine Housing Front Handle/Engine Housing Switch Shaft Throttle Trigger/ Interlock Lever

Chain Lubrication

60

10.1

Pickup Body/ Suction Hose 10.2 Valve 10.3 Tank Cap 10.4 Oil Pump 10.4.1 Removing and Installing 10.4.2 Servicing

62 63

11.

Fuel System

64

11.1 Air Filter 11.2 Carburetor 11.2.1 Removing and Installing 11.2.2 Leakage Test 11.3 Servicing the Carburetor 11.3.1 Metering Diaphragm 11.3.2 Inlet Needle 11.3.3 Fixed Jet 11.3.4 Pump Diaphragm 11.4 Adjusting Carburetor 11.4.1 User Adjustment (Carburetor without Limiter Caps) 11.4.2 User Adjustment (Carburetor with Limiter Caps) 11.4.3 Basic Setting (Carburetor with Limiter Caps) 11.5 Tank Vent 11.5.1 Machines up to 2002 11.5.2 Machines from 2002 11.6 Fuel Tank 11.6.1 Pickup Body 11.6.2 Suction Hose 11.6.3 Tank Cap 11.6.4 Replacing Engine Housing

64 65

60 61 62 62

37

8.

9. 18 21 21 22 23

10.

Removing and Installing the Engine Cylinder Piston Piston Rings Crankshaft

48 48 49 49 51 52 52

53 53 54 56

12.

65 66 67 67 68 69 69 71 71 72 73 74 74 75 76 76 76 77 77

Special Servicing Tools

79

Servicing Aids

81

56 56

13.

57 58 59

q © ANDREAS STIHL AG & Co. KG, 2004

MS 290, MS 310, MS 390

1

1.

Introduction

This service manual contains detailed descriptions of all the typical repair and servicing procedures for this power tool. As the design concept of models MS 290, MS 310 and MS 390 is almost identical, the descriptions and servicing procedures in this manual generally apply to all three models. Differences are described in detail.

The special tools mentioned in the descriptions are listed in chapter "Special Servicing Tools" of this manual. Use the part numbers to identify the tools in the "STIHL Special Tools" manual which lists all the special servicing tools currently available from STIHL. Symbols are included in the text and pictures for greater clarity. The meanings are as follows:

You should make use of the illustrated parts lists while carrying out repair work. They show the installed positions of the individual components and assemblies.

In the descriptions:

Refer to the latest edition of the relevant parts list to check the part numbers of any replacement parts.

: = Action to be taken that is not shown in the illustration (above the text)

A fault on the machine may have several causes. To help locate the fault, consult the chapter on "Troubleshooting" and the "STIHL Service Training System".

In the illustrations:

Refer to the “Techn