Husqvarna 966451906 User Manual

Workshop Manual

555 560XP/XPG

562XP/XPG

English

Contents

Workshop Manual

Husqvarna 555, 560XP, 560XPG, 562XP and

562XPG

Contents

Index ...................................................................... 4

Introduction and safety instructions .................. 6

Technical data ......................................................10

Service tools ....................................................... 12

Service data .........................................................14

Safety equipment ................................................ 16

Repair instructions .............................................. 24

Carburettor .......................................................... 34

Troubleshooting ...................................................56

Husqvarna AB has a policy of continuous product development and therefore reserves the right to modify
the design and appearance of products without prior notice.

English - 3

Index

B

Index

M

Bar bolt 54

Replacing the bar bolt 53

C

Carburettor 34

Assembly 38
Cleaning and inspection 38
Design 34
Dismantling 36
Function 35
Pressure testing the carburettor 40

Centrifugal clutch 30

Assembly of centrifugal clutch 31
Cleaning and inspection 30
Dismantling the centrifugal clutch 30

Chain brake 17

Assembling the chain brake 18
Cleaning and inspection 17
Dismantling the chain brake 17

Chain catcher 20

Replacing the chain catcher 20

Crankshaft and crankcase 49

Assembling a complete crankshaft 54
Dismantling the crankcase and crankshaft 49

F

Fuel system 44

Replacing the fuel lter 44
Replacing the fuel hose 44

I

Ignition module and flywheel 28

Assembling the ignition module and ywheel 29
Cleaning and inspection 28
Dismantling the ignition module and ywheel 28

Intake system 32

Assembling the intake system 33
Cleaning and inspection 33
Dismantling the intake system 32

Introduction and safety instructions 7

General 7
General Instructions 8
Modications 7
Numbering 7
Safety 7
Special Instructions 8
Structure 7
Target group 7
Tools 7

Muffler 19

Assembling the mufer 19
Dismantling the mufer 19

O

Oil pump and screen 31

Assembling the oil pump and screen 32
Cleaning and inspection 31
Dismantling the oil pump and screen 31

P

Piston and cylinder 45

Assembling the piston and cylinder 47
Dismantling the piston and cylinder 45
Faults and causes 47
Pressure testing the cylinder 48

S

Service data 14
Service tools 12
Starter 25, 26

Cleaning and inspection 25
Cleaning and inspection: 26
Dismantling the starter 25
Replacing a broken or worn starter cord 26
Replacing a broken return spring 27
Starter assembly 27

Stop control 20

Dismantling the stop control 20, 21

Stop function 21

Resistance test - stop function 21

Symbols

Symbols in the Workshop Manual 9
Symbols on the saw 9

T

Tank unit 42

Assembly 43
Dismantling 42

Tank valve 42
Technical Data 10
Threads 54

Repairing damaged threads 54

Throttle control lock, throttle lock and spring 22

Assembling the throttle lockout, throttle control

and spring 23
Cleaning and inspection 22
Dismantling the throttle control lock, throttle

control and spring 22

Troubleshooting 57

Troubleshooting methods 58

4 - English

V

Vibration damping system 43

Assembly 43
Cleaning and inspection 43
Dismantling 43

Index

English - 5

Introduction and safety instructions

2 Introduction and safety regulations

Contents

2.1 General ...........................................................................................................................7

2.2 Safety .............................................................................................................................7

2.3 Target group ...................................................................................................................7

2.4 Modications....................................................................................................................7

2.5 Tools ...............................................................................................................................7

2.6 Structure .........................................................................................................................7

2.7 Numbering ......................................................................................................................7

2.8 General instructions ........................................................................................................8

2.9 Special instructions .........................................................................................................8

2.10 Symbols on the saw .......................................................................................................9

2.11 Symbols in the Workshop Manual ..................................................................................9

6 - English

Introduction and safety instructions

2 Introduction and safety instructions

2.1 General

This Workshop Manual describes in detail how
to be troubleshoot, repair and test the chain saw.
A description of different safety steps that must be
taken during repair work is also given.

2.2 Safety

Note: The section dealing with safety must be
read and understood by all those carrying out
repair work or service on the chain saw.

Warning symbols can be found in this Workshop
Manual and on the chain saw. See “Symbols on
the saw” and “Symbols in the Workshop Manual”.
A new warning symbol decal must be applied as
soon as possible if a warning symbol on the chain
saw has been damaged or is missing so that the
greatest level of safety can be maintained when
using the chain saw.

2.3 Target group

This Workshop Manual is written for personnel who
are assumed to have general knowledge of repair­ing and servicing chain saws.

The Workshop Manual must be read and under­stood by personnel who will carry out repair work
and service on the chain saw. The Manual is also
suitable for use when training new employees.

2.4 Modifications

Any modications to the chain saw will be gradually
introduced into ongoing production. As these modi­cations affect service and/or spare parts, specic
service information will be sent out on each occa­sion. This means that in time this Workshop Manu­al will become out of date. In order to prevent this,
the Manual should be read together with all service
information concerning the chain saw in question.

2.5 Tools

Special tools are required for some stages. All
service tools are listed in the Workshop Manual.
Usage is made apparent in each section.

Always use Husqvarna’s original:

• Spare parts

• Service tools

• Accessories

2.6 Structure

This Workshop Manual can be used in two different

ways:

• Repair of a specic system on the chain saw.

Dismantling and assembly of the entire chain saw.

•

Repair of a specific system

When a particular system on the chain saw is to be

repaired, proceed as follows:

1. Look up the page for the system in question.

2. Carry out the following steps:
Dismantling

Cleaning and inspection

Assembly

Dismantling and assembling the chain saw.

Proceed as follows when the chain saw is to be
dismantled and assembled:

1. Open the “Repair instructions” chapter which

deals with the Starter and carry out the in­structions outlined under the Dismantling

heading.

2. Work forward in the Manual and carry out Dis-
mantling in the order set out in the sections.

3. Go back to the Starter and carry out the in­structions under Cleaning and Inspection.

4. Work forward in the Manual and carry out

Cleaning and Inspection in the order set out

in the sections.

5. Order or collect all requisite spare parts from
the stores.

6. Look up the “Repair instructions” chapter which

deals with the Crankcase and carry out the
instructions outlined in Assembling.

7. Work back in the Manual and carry out Assem-
bling in the order set out in the sections.

Some sections include an introductory Descrip-
tion of the actual unit in order to increase the basic

understanding.

2.7 Numbering

Position references to components inside the g­ures are designated A, B, etc.
The gures are numbered 1, 2 etc.
The position references and gure numbers restart

English - 7

Introduction and safety instructions

2.8 General Instructions

The workshop where the chain saw is to be re­paired must be equipped with safety equipment in
accordance with local regulations.

No one may repair the chain saw unless they have
read and understood the content of this Workshop
Manual.

This workshop manual contains the following warn­ing boxes in relevant places.

WARNING!
The warning box warns of the risk
of personal injury if the instruc­tions are not followed.

NOTE!
This box warns of material damage if the

instructions are not followed.

2.9 Special Instructions

The fuel used in the chain saw has the following
hazardous properties:

• The uid and its vapour are poisonous.

• Can cause eye and skin irritation.

• Can cause breathing problems.

• Is highly inammable.

When using compressed air, do not direct the jet
towards your body. Air can penetrate into the blood
stream, which can endanger life.

Wear protective earplugs or earmuffs when test
running.

After test running, do not touch the mufer until
it has cooled down. Risk of burns. Use protective
gloves when working with the mufer.

Do not start the chain saw unless the bar, chain
and clutch cover (chain brake) are tted, otherwise
the clutch may loosen and cause personal injury.

Insufcient chain lubrication can result in chain
breakage, which can cause serious or even life­threatening injury.

Exercise care to ensure the starter spring does not
y out and cause personal injury. Wear protective
glasses. If the spring tension is activated on the
starter pulley when it is to be taken up, the spring
can y out and cause personal injury.

Check that the brake is applied when removing the
pressure spring on the chain brake. Otherwise the
pressure spring can y out and cause personal
injury.

After repairing, check the chain brake, see “Assem­bling chain brake \ Function check”.

Keep in mind the re risk. The chain saw may emit
sparks, which cause ignition.

Check the chain catcher and replace it if it is dam­aged.

8 - English

Introduction and safety instructions

2.10 Symbols on the saw

The symbols below are embedded on the chain
saw.

Choke Lever

Refuelling

Stop button

2.11 Symbols in the Workshop Manual

This symbol warns of personal injury
when the instructions are not followed.

Chain oil ll.

Chain brake

Decompression valve

Fuel pump

Adjusting the oil pump

English - 9

Technical data

3 Technical data

Displacement Cylinder diameter Stroke length Max. output/speed
cm3/cubic inch Ø mm/Ø inch mm/inch kW/hp/ rpm

555: 59,8 / 3.65 46 / 1.81 36 / 1.42 3.1 / 4.2 / 9600
560XP/XPG: 59,8 / 3.65 46 / 1.81 36 / 1.42 3.5 / 4.8 / 9600
562XP/XPG: 59,8 / 3.65 46 / 1.81 36 / 1.42 3.5 / 4.8 / 9600

Electrode gap Ignition system Air gap Carburettor type
mm/inch mm/inch

555: 0,5 / 0.02 SEM 0,3 / 0.012 Zama
560XP/XPG: 0,5 / 0.02 SEM 0,3 / 0.012 Zama
562XP/XPG: 0,5 / 0.02 SEM 0,3 / 0.012 Zama

Usable cutting length Chain speed at Chain pitch Drive link
cm/inch max. output - speed mm/inch mm/inch
m/s - rpm

555: 33-61 / 13-24 21,3 / 9600 8.25 / 0.325 9,53 / 0.375 1.3 / 0.050 - 1,5 / 0.058
560XP/XPG: 33-61 / 13-24 21,3 / 9600 8,25 / 0.325 9,53 / 0.375 1,3 / 0.050 - 1,5 / 0.058
562XP/XPG: 38-71 / 15-28 21,3 / 9600 9,53 / 0.375 1,3 / 0.050 - 1,5 / 0.058

10 - English



GAS

OIL

Technical data

Engage speed Spark plug Automatic oil pump
rpm

555: 3800 NGK CMR6H Yes
560XP/XPG: 3800 NGK CMR6H Yes
562XP/XPG: 3800 NGK CMR6H Yes

Volume fuel tank Capacity oil pump at Volume oil tank
Litre/US. pint 9,000 rpm, Litre/US. pint
ml/min

555: 0,65 / 1.37 6-15 0.33 / 0.70
560XP/XPG: 0,65 / 1,37 6-15 0,33 / 0.70
562XP/XPG: 0,65 / 1.37 8-18 0,35 / 0.74

Weight without bar and chain Weight with bar and chain
kg/lbs kg/lbs

555: 5,6 / 12.3 Weight depending on selected cutting equipment
560XP/XPG: 5,6 / 12.3
562XP/XPG: 5,7 / 12.6

English - 11

Service tools

4 Service tools

1 2

3 5

4 mm

7

4

4 mm
5 mm

6

8

9

10

12 - English

11

12a

12b

Service tools

13c

15

13a13d

13b

14

16

17

Pos Description Used for Order No.

1 Piston stop Locking the crankshaft 575 29 36-01

2 Hook for fuel lter Suspending the fuel lter 502 50 83-01
3 Allen key, 4 mm For M5 bolts 502 50 87-01
4 Allen key, 4 mm For M5 bolts 502 50 18-01

4 Allen key, 5 mm For M6 bolts 502 50 64-01
5 Air gap tool Setting, ignition module 502 51 34-02
6 Clutch tool Centrifugal clutch 575 25 14-01

7 Assembly xture Securing the chain saw 502 51 02-01
8 Pressure gauge Pressure testing 531 03 06-23

9 Test spark plug Checking the ignition module 501 97 64-01

10 Assembly pliers Fitting the spark plug guard 502 50 06-01
11 Dismantling device Dismantling the crankcase 575 28 69-01

12a Assembly tool Assembling the sealring 575 34 70-01

12b Guide sleeve Assembling the sealring 575 34 69-01

13a Cover plate, outlet Closure of outlet 574 71 14-01

13b Cover plate, inlet Closure of inlet 575 29 81-01

13c Cover plug, inlet Closure of inlet 574 70 12-01

13d Pressure tester Pressure testing the cylinder 503 84 40-03

14 Mandrel Dismantling the ywheel 502 51 94-01

15 Assembly tool Assembling the crankshaft 502 50 30-23

16 Puller Dismantling the crankshaft 531 00 48-67

17 Engine Diagnostic Tool Diagnosis and troubleshooting 576 69 23-01

English - 13

Service data

18-20Nm 16mm

5 Service data

12-14Nm 13mm

12-15 Nm 5mm

12-15 Nm 5mm

1-2Nm

8-10Nm 4mm

1,5-2Nm 4mm

1-2Nm

5-6Nm 4mm

1-2Nm

Min. 15Nm 13mm

1-2Nm

Key

The numbers by the components to be assembled with
screws state the tightening torque in Nm.

4-5Nm 4mm

Min. 25Nm

s = Lubricate using two-stroke oil.
n = Lubricate using chain oil.
l = Lubricate using grease.

14 - English

Service data

9-11Nm 4mm

9-11Nm 4mm

1-2Nm

3-4Nm 4mm

22-25Nm 13mm

6-8Nm 4mm

7-9Nm 4mm

3-4Nm 4mm

3-4Nm 4mm

6-8Nm 4mm

4-5Nm 4mm

2-3Nm 4mm

3-4Nm 4mm

7-9Nm 4mm

8-10Nm 4mm

3,5-4,5Nm 4mm

3,5-4,5Nm 4mm

English - 15

Safety equipment

6 Safety equipment

Contents

6.1 Dismantling the chain brake ...........................................................................................17

6.2 Assembling the chain brake ............................................................................................18

6.3 Dismantling the mufer ...................................................................................................19

6.4 Assembling the mufer ...................................................................................................19

6.5 Replacing the chain catcher ...........................................................................................20

6.6 Dismantling the start/stop control ...................................................................................20

6.7 Assembling the start/stop control ....................................................................................21

6.8 Resistance test - stop function .......................................................................................21

6.9 Dismantling the throttle control lock, throttle control and spring ..................................... 22

6.10 Assembling the throttle control lock, throttle control and spring .....................................23

16 - English

6 Safety equipment

6.1 Dismantling the chain brake

1

Remove the cylinder cover.
Release the brake by moving the front hand guard
backward.
Loosen the bar nuts and remove the clutch cover,
bar and chain, see g. 1.

2

Unscrew the kickback guard and remove it.
NOTE! Make sure that the spring and rocker do not
y out.
Carefully tighten the clutch housing in a vice. Re­lease the brake by using the saw’s hand guard as
a tool. Mesh with the brake and tighten anti-clock­wise until the brake is activated, see g. 2.

Safety equipment

Fig 1

Alt. 1

Alt. 2

3

Loosen the screws and insert a screwdriver to
maintain pressure on the spring, and then carefully
remove the cover over the brake spring, see g. 3.

WARNING!
Exercise care to ensure the spring
does not fly out and cause personal
injury. Wear protective goggles.

4

Hold one hand on top of the brake spring and
press in a small screwdriver into the spring. Care­fully bend upwards until the spring is released and
it slides onto the screwdriver, see g. 4.

Cleaning and inspection

• Clean and check carefully all components. Parts
must be replaced if cracked or show signs of
other defects. Always use original spare parts.

Fig 2

Fig 3

Fig 4

• Measure the thickness of the chain brake band.

It must not be less than 0.6 mm in any place.
See gure 5.

• Lubricate the knee joint with grease.

Fig 5

English - 17

Safety equipment

6.2 Assembling the chain brake

1

Screw the knee joint and the brake band together
(see gure 5) using a tightening torque of 1-1.5
Nm. Place the knee joint with the tted chain brake
band in the opening in the clutch cover. The space
for the spring in the cover must be lubricated with
grease. See gure 6.

2

Compress the spring with a wide screwdriver and
press it down with your thumb. See gure 7.

WARNING!
Exercise care to ensure the spring
does not fly out and cause personal
injury. Wear protective goggles.

Fig 6

Fig 7

3

Fit the cover over the brake spring using 1-1.5 Nm
tightening torque. See gure 8.

4

Tighten the brake by using the saw’s hand guard
as a tool. Mesh with the brake and tighten clock­wise until the brake is in the off position. See
gure 9.

5

NOTE! Make sure the bushings in the kickback
guard’s attachments are kept in place from the
inside. See gure 9.

Screw the kickback guard in place and put the
rocket in position. Position the spring (B) in the
plastic housing (C) (see gure 10) and press the
spring against the rocker and then press the plastic
housing into its groove. Tighten the chain guide
plate in place.

Fig 8

Fig 9

Fit the:

• bar

• chain

• clutch shoe

• cylinder cover

18 - English

A
B

C

Fig 10

NOTE!
After repairing, the chain brake must be in-

spected in line with the instruction below.

Functional inspection:

Do not turn on the motor when carrying out this
inspection.

Bar length Height

38 cm/15” 50 cm/20"

• Hold the chain saw over a stable surface. The
distance between the bar and the surface is
shown in the table above.

• Let go of the front handle and let the chain saw
drop toward the surface underneath.

• When the bar hits the surface the chain brake
must trigger.

6.3 Dismantling the muffler

WARNING!
Do not touch the muffler until it
has cooled. Risk of burns.

Safety equipment

Fig 11

1

Remove the cylinder cover, mufer, gasket and
cooling n.

2

The saw is tted with spark arrestor mesh, which is
removed. If necessary, use the combination span­ner to push down the plate edge and remove the
spark arrestor mesh. See gure 12.

Cleaning and inspection

Clean and check all components carefully.
Parts must be replaced if cracked or show signs of
other defects. Always use original spare parts.
The spark arrestor mesh is best cleaned with a
wire brush.
The mesh must be replaced, if damaged.
The saw will overheat if the mesh is clogged result­ing in damage to the cylinder and piston.
Never use a saw with a clogged or defective mufer.

6.4 Assembling the muffler

1

If the saw is tted with a spark arrestor mesh, put
it in place rst. When tting the mesh, make sure
that the mesh is inserted in the right position. If
necessary, use the combination spanner to insert
the mesh.

2

Fit the:

• cooling n

Fig 12

• gasket

• mufer, tightening torque of 12-14 Nm.

• Cylinder cover

3

Warm up the saw for at least one minute and
retighten the screws on the mufer to 12 to 14 Nm.

English - 19

Safety equipment

6.5 Replacing the chain catcher

A worn chain catcher must always be replaced with
a new one. Always use original spare parts.

1

Release the brake by moving the front hand guard
backward.
Loosen the bar nuts and remove the clutch cover,
chain and bar.

2

Remove the chain catcher and replace it with a
new one.
Make sure that the vibration element is tted cor­rectly on the crankcase when a new chain catcher
is screwed in place. See gure 13.

6.6 Dismantling the start/stop control

1

Remove the cylinder cover and air lter. Dismantle
the air lter holder. See the “Dismantling the carbu­rettor” chapter.

Fig 13

2

Loosen screw B and dismantle the stop control A.
See gure 14. Unhook the rubber collar around the
control from the guide plugs.

Cleaning and inspection

Clean and check carefully all components. Parts
must be replaced if cracked or show signs of other
defects. Always use original spare parts.

Fig 14

20 - English

6.7 Assembling the start/stop control

1

Fit the new stop control (A) and tighten screw (B) in
place at a torque of 1 Nm. Slide in the stop control
in the rubber sleeve C and hook the sleeve on the
guide taps. See gure 15.

Safety equipment

Fig 15

2

Attach the cables as outlined in gure 16.

3

Attach the air lter holder. See the “Assembling the
carburettor” chapter.

4

Fit air lter and cylinder cover.

6.8 Resistance test - stop function

Dismantle the ignition module as outlined in
“7.7 Dismantling the ignition module and ywheel”.
Cut open the shrink tube covering both cables and
shrink tubing that encloses the cable ends.

Clean the contact areas and check resistance in
the following way:
Test the resistance by connecting a multimeter to
the cable ends. NOTE! The power switch must be
in the “on” position to get the correct reading. See
gure 17.
The stop switch is in the “on” position when the
button is held down (see gure 17) and in the “off”
position when the button is in neutral.
Resistance can be 0.5 Ohm at most with the power
switch in the “on” position.
When assembling (see gure 18), pull the cable
ends apart and slide on a thicker shrink tube over
both cables. Then slide on the thinner shrink tubes
over each cable. Connect the cable ends together.
Slide the thinner shrink tubes over the cable ends
and heat the shrink tube rst on both cables sepa­rately. Slide the thicker shrink tube over the thinner
shrink tubes and then heat the thicker shrink tube.

Fig 16

Fig 17

Fig 18

English - 21

Safety equipment

6.9 Dismantling the throttle control
lock, throttle control and spring

1

Loosen the screw on the rear handle. Remove the
handle insert (A). See gure 19.

2

Loosen the throttle control lock (B) as shown in the
gure using a screwdriver or similar tool. Remove it
then from the shaft in the handle. See gure 20.

3

Press out the throttle control pin (C) with the help
of a punch. See gure 21.

A

Fig 19

Fig 20

4

Loosen the throttle cable (D) and lift out the throttle
control and the spring. See gure 22.

5
Cleaning and inspection

• Carefully clean and check all parts. See gure

13. Parts must be replaced if cracked or show
signs of other defects. Always use original
spare parts.

• Check that the spring is intact and retains all its

tension.

Fig 21

Fig 22

22 - English

Fig 23

6.10 Assembling the throttle control

lock, throttle control and spring

1

Lubricate the pin and joined surfaces with a light
oil. Hook on the throttle cable (D). Slide in the
throttle control and make sure the spring is tted as
outlined in gure 24.
NOTE! Make sure that the rear end of the throttle
control is correctly aligned inside the cut-out edg­ing before the pin is pressed in place.

2

Fit the throttle control’s pin (C) using a punch. See
gure 25.

Safety equipment

Fig 24

C

3

Fit the throttle control lock (B) by sliding it on the
shaft in the handle. See gure 26. Make sure the
spring is positioned inside the throttle control lock
when you press it down so that the barbs are
hooked in place.

4

Fit the handle insert using a screw, when the
throttle control, spring, throttle cable and throttle
control lock with pin are tted correctly.

Fig 25

Fig 26

English - 23

Repair Instructions

7 Repair instructions

Contents

7.1 Dismantling the starter ....................................................................................................25

7.2 Replacing a broken or worn starter cord ........................................................................26

7.3 Tensioning the return spring ...........................................................................................26

7.4 Replacing a broken return spring ...................................................................................27

7.5 Starter assembly..............................................................................................................27

7.6 Dismantling the ignition module and ywheel .................................................................28

7.7 Assembling the ignition module and ywheel .................................................................29

7.8 Dismantling the centrifugal clutch ...................................................................................30

7.9 Assemby of centrifugal clutch .........................................................................................31

7.10 Dismantling the oil pump and screen .............................................................................31

7.11 Assembling the oil pump and screen ..............................................................................32

7.12 Dismantling the intake system ........................................................................................32

7.13 Assembling the intake system ........................................................................................32

7.14 Carburettor .....................................................................................................................34

7.15 Tank unit .........................................................................................................................42

7.16 Venting the fuel tank .......................................................................................................42

7.17 Vibration damping system ..............................................................................................43

7.18 Replacing the fuel lter ...................................................................................................44

7.19 Replacing the fuel hose/return hose ...............................................................................44

7.20 Replacing the fuel pump ..................................................................................................44

7.21 Dismantling the piston and cylinder ................................................................................45

7.22 Assembling the piston and cylinder ................................................................................47

7.23 Pressure testing the cylinder ..........................................................................................48

7.24 Dismantling the crankshaft and crankcase .....................................................................49

7.25 Assembling the complete crankshaft ..............................................................................54

7.26 Replacing the bar bolt .....................................................................................................53

7.27 Repairing damaged threads ............................................................................................54

24 - English

7 Repair instructions

7.1 Dismantling the starter

1

Loosen the four screws, which hold the starter
against the crankcase and remove the starter.

2

Pull the cord out about 30 cm and lift it into the
notch on the outside of the starter pulley. Release
the tension in the return spring by letting the starter
pulley rotate anti-clockwise. See gures 1 and 2.

Repair Instructions

WARNING!
If the spring tension is activated
on the starter pulley, the spring
can fly out and cause personal
injury. Wear protective glasses.

3

Loosen the screw in the centre of the pulley and
remove the pulley. See gure 3. Loosen the screws
on the cassette and remove the cassette and
spring.

Cleaning and inspection

Clean the parts and check:

• The starter cord.

Fig 1

Fig 2

• That the starter pawls on the ywheel are intact,
i.e. that they spring back to the centre and
move easily.

• To lubricate the return spring using light oil.

Fig 3a

English - 25

Repair instructions

7.2 Replacing a broken or worn starter
cord

When the starter cord is worn and must be replaced,
the tension in the return spring must be released.

1

Pull the cord out about 30 cm and lift it into the
notch on the outside of the starter pulley. Release
the tension on the return spring by allowing the
starter pulley to rotate slowly backwards.

WARNING!
If the spring tension is activated on
the starter pulley, the spring can fly
out and cause personal injury.
Wear protective glasses.

2

Loosen the screw in the centre of the pulley and
remove the pulley. See gure 3a.

3

When the starter pulley is removed, insert a new
starter cord and attach it to the starter pulley.
Thread the other end of the starter cord through
the hole in the starter housing and starter handle
and tie a double knot on the cord. Wind approx. 3
turns of the starter cord on the starter pulley. Turn
the starter pulley until it latches into the correct po­sition. Tighten the screw at the centre of the starter
pulley, at a tightening torque of 2-3 Nm.

Fig 3b

Cleaning and inspection:

• Clean and check carefully all components. Worn
or damaged parts must be replaced. Lubricate
the return spring with a light oil.

7.3 Tensioning the return spring

1

Pull the starter cord up into the notch in the starter
pulley and turn the pulley about 3 turns clockwise.
Check that the pulley can be turned at least a fur­ther 1/2 turn when the starter cord is pulled all the
way out. See gure 4.

2

Stretch the line with the handle. Remove your
thumb and let the cord spin back. See gure 5.

Fig 4

26 - English

Fig 5

7.4 Replacing a broken return spring

WARNING!
Exercise care to ensure the spring
does not fly out and cause person­al injury. Wear protective goggles.

1

Loosen the screw at the centre of the starter pulley
and loosen the screws on the cassette. Remove
the starter pulley with the cassette and spring.

2

Remove the broken cassette and replace it with a
new one.

3

Tighten the screw at the centre of the starter pulley,
at a tightening torque of 2-3 Nm. Load the return
spring, see “Loading the return spring”. See also
the “Dismantling the starter” chapter.

Repair Instructions

7.5 Starter assembly

1

Position the starter against the crankcase and
tighten the screws at a tightening torque of
3-4 Nm.

English - 27

Repair Instructions

7.6 Dismantling the ignition module

and flywheel

1

Remove the cylinder cover. Remove the starter.
Snap off the ignition cable from the guide rail and
remove the guide rail. See gure 7.

2

Knock out a few of the pins in the tool if it does not
match up with the ywheel.
Use the tool to hold the ywheel in place while the
ywheel nut is loosened using a suitable socket
wrench. See gure 8.

Fig 7

4

Thread the mandrel on the crank pin. Screw in until
1-2 threads are left to the ywheel. Knock on the
mandrel with a suitable metal hammer while at the
same time pulling the ywheel outward until the
ywheel comes off the shaft. Remove mandrel and
ywheel. See gure 9.

Unscrew the air nozzle to replace the ignition mod­ule. Loosen the screws on the ignition module. See
gure 10.

Dismantle the air lter, air lter holder and carburet­tor. See the “Dismantling the carburettor” chapter.

Dismantle the tank unit as outlined in the “Disman­tling the tank unit” chapter.

Dismantle the intake system, see the “Dismantling
the intake system” chapter.

Fig 8

Fig 9

Loosen the earth cable. See gure 11. Pull the
cables through the openings in the crankcase.

Cleaning and inspection

• Clean all parts, especially the tapers on the
ywheel and shafts.

• Check the ywheel for cracks or any other signs
of damage.

28 - English

Fig 10

7.7 Assembling the ignition module and
flywheel

1

Run the cables through the opening in the crank­case. Screw the earth cable in place. See gure 11.
Fit the cabling to the stop button.

2

Position the cable channel as outlined in gure 10.
NOTE! Take care that the cable channel is posi­tioned correctly under the ignition module so that
the cables are not crushed.

3

Place the ignition module in position. See gure 13.
Do not tighten the screws.

Repair Instructions

4

Fit the ywheel onto the crankshaft pin. Turn the
ywheel until the key ts into the key slot on the
shaft. See gure 12.
Tighten the screw for the ywheel.

5

Insert the plastic air gap tool, at a thickness of

0.3 +- 0.1 mm, between the lugs on the ignition
module and ywheel. Turn the ywheel so that the
magnets are positioned opposite the ignition mod­ule. Tighten the screws, at a tightening torque of

4.5- 6 Nm. Remove the plastic air gap tool. Fit the
intake system as outlined in “7.14 Assembling the
intake system”, the tank unit as outlined in “7.16
tank unit”, and the air lter as outlined in “Assem­bling the carburettor”.

6

Press the ignition lead into the holder on the parti­tion wall.

7

Then t:

• The air nozzle

Fig 11

Fig 12

Fig 13

• The guide rail and press the cable in place

• the spark plug hat by unscrewing the piston stop.

•

The starter, at a tightening torque of 2.5-3.5 Nm

• The cylinder cover

English - 29

Repair Instructions

7.8 Dismantling the centrifugal clutch

1

Remove the cylinder cover. Release the brake by
moving the kickback guard backwards. Loosen the
bar nuts and remove the clutch cover, chain and
bar. See gure 14.

2

Loosen the spark plug hat and remove the
spark plug, and insert the plastic piston stop
(575 29 36-01). See gure 15.

3

Loosen the clutch using tool 575 25 14-01nd a suit­able socket wrench or combination spanner. Turn
the clutch clockwise to loosen it. See gure 15.

Fig 14

4

Secure the clutch in a vice as shown in gure 16.
Carefully remove the clutch springs. Remove the
clutch shoe springs from the side that does not
have text.

NOTE!
Be careful with the clutch springs, as

opening them too much can result in
material damage.

Cleaning and inspection

• Clean and check all parts carefully. Parts must
be replaced if cracked or showing signs of
other defects. Always use original spare parts.

• Check the thickness of the clutch shoes by meas­uring them with slide callipers across the whole
clutch hub. If the thickness is below 60 mm, the

clutch must be replaced. See gure 16.

Fig 15

Min 60 mm

Fig 16

30 - English

7.9 Assembly of centrifugal clutch

1

Insert the clutch springs on the side of the shoes
without text. See gure 17.

2

Screw in the clutch (anti-clockwise) until it stops.
Then tighten the clutch using tool 575 25 14-01
and a suitable socket wrench or combination span­ner. Tightening torque of at least 25 Nm.

3

Remove the piston stop and t the spark plug
using a tightening torque of 20 Nm and the spark
plug hat.

Then t:

• The cylinder cover

• The bar

• The chain

• The clutch cover

Repair Instructions

Fig 17

7.10 Dismantling the oil pump and
screen

1

Empty and clean the oil tank.
Dismantle the centrifugal clutch as outlined in
“Dismantling the centrifugal clutch”.

2

Loosen the clutch drum, the drive sprocket, the
needle bearing and the pump drive wheel. See
gure 18.

3

Unscrew the chain guide plate. See gure 19.

4

Loosen the screws on the oil pump from the crank­case and remove it together with the oil pressure
hose. See gure 20.

Cleaning and inspection

• Clean and check all parts carefully. Parts must
be replaced if cracked or showing signs of
other defects. Always use original spare parts.

Fig 18

Fig 19

• Lubricate all moving parts with chain oil.

Fig 20

English - 31

Repair Instructions

7.11 Assembling the oil pump and screen

1

Lower the oil lter in place and replace the oil pump
as outlined in gure 19 and tighten the screws.

2

Fit the pump drive wheel, the needle bearing, the
drive sprocket, the clutch drum and the clutch, us­ing a tightening torque of 25 Nm.

3

Adjust the oil pump. See Figure 21.

4

Fit the clutch. See the “Assembling the centrifugal
clutch” chapter.

5

Fit the chain, bar and clutch cover.

WARNING!
Insufficient chain lubrication can
result in chain breakage, which
can cause serious personal injury.

Fig 21

7.12 Dismantling the intake system

The intake system consists of:

• The inlet manifold, A

• The partition wall, B

• The intake ange, C

See Figure 22.

1

Dismantle the cylinder cover.

2

Loosen screws D and the movement limiter E as
outlined in gure 23. Loosen the ignition cable.

Fig 22

D

D

32 - English

Fig 23

D

D

E

3

Dismantle the air lter, the lter holder, the cable
from the intake ange holder and the carburettor
and the throttle cable as outlined in “Dismantling
the carburettor”. NOTE! The lug on the carburettor
sits on the bracket on the partition wall.

4

Hook off the cabling from the holder on the intake
system (J). Knock out the POP-out window using a
screwdriver. See gure 25. Lower the tank slightly
and slide the fuel hose down into the hole. Loosen
the lower screws of the intake system using the
POP-out hole and the fuel hose hole. Loosen the
other screws.

Repair Instructions

Fig 24

5

Dismantle the intake system. Pull up and then out­ward. See gure 26.

Cleaning and inspection

Clean and check all parts carefully. Parts must
be replaced if cracked or showing signs of other
defects. Always use original spare parts.

7.13 Assembling the intake system

1

Assemble the intake system.

2

Fit the lower screws of the intake system using the
POP-out hole and the fuel hose hole. Fit the other
screws. Fit the fuel hose and the throttle cable to
their attachments. See gure 24.
Fit the rubber grommet to the throttle cable. Push
the tank back in position. Hook on the cabling to
the holder on the intake system.

3

NOTE! Press the lug on the carburettor in place on
its bracket on the partition wall. See gure 24.

Fig 25a

Fig 25b

Fit the carburettor, the lter holder and the air lter
as outlined in “Assembling the carburettor”.

Fig 26

English - 33

Repair Instructions

7.14 Carburettor

WARNING!
The fuel used in the chain saw has
the following hazardous properties:

1. The fluid and its vapour are
poisonous.

2. Can cause skin irritation.

3. Is highly inflammable.

Description

The gures accompanying this description do not
correspond with the carburettor on the chain saw.
They show only the principle of design and func­tion.

Design

The carburettor is based on three sub-systems:

• Metering unit, A.

• Mixing unit, B.

• Pump unit, C.

The needles and the fuel’s control functions are
located in the metering unit, A. Here the correct
quantity of fuel is adjusted for the actual speed and
power output. See gure 27.

The mixing unit B houses the choke, the throttle
valve and the diffuser jets. Here air is mixed with
the fuel to give a fuel/air mixture that can be ignited
by the ignition spark. See gure 28.

In the pump unit C, fuel is pumped from the fuel
tank to the carburettor’s metering unit. One side of
the pump diaphragm is connected to the crankcase
and pulses in time with the pressure changes in
the crankcase. The other side of the diaphragm
pumps the fuel. See gure 29.

Fig 27

B

Fig 28

34 - English

Fig 29

Function

The carburettor operates differently in the following
modes:

• Cold start mode

• Idling mode

• Part throttle mode

• Full throttle mode

In cold start mode the choke valve H is completely
shut. This increases the vacuum in the carburettor
and fuel is easier to suck from all the diffuser jets
D, E, and F. The throttle valve I is partly open. The
throttle valve, J, is closed. See gure 30.

In idling mode, the throttle valves I and J are
closed and the choke valve H is open.

Air is sucked in through an aperture in the throttle
valve and a small amount of fuel is supplied
through the diffuser jet D. See gure 31.

Repair Instructions

Fig 30

In part throttle mode, the throttle valve I is partly
open and the choke valve H is fully open. Fuel is
supplied through the diffuser jets D and E. The
throttle valve, J, starts to open. See gure 32.

In the full throttle mode both valves are open and
fuel is supplied through all four diffuser jets (D, E,
F and G). The throttle valve, J, is fully open. See
gure 32.

Fig 31

Fig 32

Fig 33

English - 35

Repair Instructions

Dismantling the carburettor
1

Dismantle the cylinder cover and the air lter.

2

Loosen the screws, F. Unhook the rubber attach­ment G on both sides. See Figure 35.

3

Loosen the suction hose A, the return hose B, and
the tank bleeding hose C. See gure 34.

4

Remove the air lter holder. Let the air lter holder
remain in place in the cabling for the stop button.
Loosen the fuel hose, D. Unhook the throttle cable,
E. See gure 34.

Fig 34

5

NOTE! Press down the lug to release the carburet­tor. Lift out the carburettor. See gure 36.

NOTE!
The lug on the carburettor is securely

attached to the partition wall.

6

Use a small at screwdriver to snap open the con­nector from the black attachment. Separate the
connector by pressing down the catch with a at
screwdriver and then pulling the unit apart. See
gure 37.

Fig 35

D

E

Fig 36

36 - English

Fig 37

7

Dismantle the pump cover H and carefully remove
the control diaphragm J and gasket K.

8

Unscrew screw P and remove needle valve M with
lever arm Q, shaft L and spring R.

9

Use a needle or similar device and carefully pull up
the fuel screen (W). See gure 39.

10

If necessary, dismantle throttle valve T and choke
valve U and air valve S, and remove the shafts with
lever arms and springs (see gure 39).

11

If necessary, dismantle the AutoTune AB unit. See
gure 39.

Repair Instructions

H

J

K

L

M

Q
R

Fig 38

P

English - 37

Repair Instructions

S

T

W

X

U

Y

V

Z

AB

Cleaning and inspection

Clean all units in clean petrol.

Use compressed air to dry the petrol on the com­ponents. Direct the air through all channels in the
carburettor housing and ensure that they are not
blocked. Check the following:

1. That the gasket, pump and control diaphragms
are undamaged, as well as the gasket between
the carburettor body and the autotuner.

2. That there is no play on the throttle and choke
valve shafts.

3. That the needle valve M and its lever arm Q are
not worn. See gure 38.

4. That the fuel screen W is intact and clean. See
gure 39.

5. That the inlet manifold V is intact. See gure 39.

6. Use the service tool, Engine Diagnostic Tool
576 69 23-01, to inspect the AutoTune unit.
See separate instruction.

Assembly

Observe cleanliness when assembling the car­burettor. The slightest contamination can result in
downtime.

1. If throttle and choke valves with shafts, lever
arms and springs are removed, these must be
assembled. The spring is tensioned 1-2 turns.
Lubricate the shaft bearings using a light oil.

2. Fit the fuel screen W using the handle of a
small screwdriver. See gure 39.

3. Fit the gasket X in the carburettor as well as the
holder Y. Screw in place screw Z as outlined in
gure 39.

4. See gure 39 on how to assemble the
AutoTune AB unit with gasket.

Note! When replacing the AutoTune unit or car-

burettor with an AutoTune unit, the unit must rst
be programmed before it can be used. Refer to
the local support page for more information.

Fig 39

38 - English

4. Assemble needle valve M with lever arm Q,
shaft L and spring R, and tighten screw P.
(Fit the expansion washer). See gure 40.

Repair Instructions

Fig 40

5. Check using a ruler or the like that the lever is
level with the assembly plane on the cover.
If necessary, the lever arm can be bent, see
gure 41.

7. Fit gasket K, the control membrane J and the
pump cover H. See gure 42.

8. Carry out a pressure test.

Fig 41

H

J

Fig 42

K

English - 39

Repair Instructions

Pressure testing the carburettor

Pressure testing should be carried out with the car­burettor fully assembled. Testing should always be
carried out after the carburettor has been repaired,
but a test can also be made for troubleshooting
before dismantling.
Option 1
See the gure and carry out the check as follows:

1

Connect pressure tester to the carburettor fuel inlet.

2

Submerge the carburettor into a container with
water. See gure 43.

3

Pump up the pressure to 20 kPa.

4

No leakage is permitted. If a leakage occurs refer
to the table below.
Option 2

1

Plug the connections to the fuel inlet.

2

Create a vacuum to the purge nipple on the car­burettor. No leakage is permitted. In the case of
leakage, leakage spray can be used even it if is dif­cult. Try and identify where the spray is absorbed.
It can be used to show leakages in main jets, idling
needles, measuring cover gaskets and measuring
diaphragms, and autotune gaskets.

Leak in Fault with

Fig 43

Diffuser jets Needle valve
Leak in the impulse pipe Pump membrane
Ventilation hole on the Control membrane
metering unit.

Fitting on the saw
1

Press the connector together as outlined in gure
44 and push it into place in the holder.

Fig 44

Fig 45

40 - English

2

Make sure the cabling is tted to its mounting on
the intake ange.
Press the fuel hose (D) in place in the collar on the
intake bellows.
Hook on the throttle cable (E) in its mounting on
the intake bellows. See gure 46.
Make sure the lug on the carburettor hooks in
place on its mounting on the intake system.

Make sure that the following components are
correctly fitted:

• Position the air lter holder against the carburettor.

• Make sure the carburettor cover’s intake channel
is aligned correctly with the slot for the air lter
holder.

• The spring must be tted under the choke pin on
the carburettor. See gure 47.

• The rubber collar on the stop button must be on
the inside of the bottom of the carburettor com­partment. See gure 47.

• NOTE! Make sure that the fuel and return hoses
are not crushed.

Repair Instructions

D

E

Fig 46

3

Position the guide taps on the air lter holder in the
rubber grommets, G. See gure 48.

4

Hook on the throttle cable, E. See gure 46.
Fasten the return hose B and secure it in its mount­ings on the air lter holder.
Attach the pressure hose A, with the short hose on
the short plastic plug on the fuel pump.
Attach the tank bleeding hose, C. See gure 49.

5

Hook it on the left side and then the right side of
the carburettor in the rubber mounting. Then screw
the carburettor in place. See gure 48.

Fig 47

Fig 48

6

Fit the air lter.

Fig 49

English - 41

Repair Instructions

7.15 Tank unit

WARNING!
The fuel used in the chain saw has

the following hazardous properties:

1. The fluid and its vapour are poisonous.

2. Can cause skin irritation.

3. Is highly inflammable.

Dismantling

1. Drain the fuel from the tank.

2. Remove the cylinder cover, the clutch cover, the
chain and the bar. See the Operator’s Manual.
Dismantle the carburettor as outlined in “Dis­mantling the carburettor”.

3. Loosen the hoses A to D. See gure 50.

4. Loosen the screws F. See gure 51.

5. Loosen the movement limiter H. See gure 53.

6. Pull out the hoses A to D in the bottom of the car­burettor compartment. Unhook the throttle cable,
E, from the intake bellows before pulling out from
the bottom of the carburettor compartment.

Fig 50

NOTE!
Exercise care so that the fuel hose and

throttle cable are not damaged.

7.16 Venting the fuel tank

The two-way valve has the following properties:

• Controlled opening pressure in both directions,
which prevents a positive pressure or a vacu­um developing in the fuel tank and impairing
engine performance. This also prevents fuel
leakage.

• Opening pressure outward 100-450 mbar.

• Opening pressure inward (vacuum) max.
70 mbar. (2 locations)

Test
Opening pressure outwards:

1. Open the tank lock and leave it open during the
entire test. Drain the fuel from the tank.

2. Loosen the positive pressure hose as outlined
in gure 54. Connect the pump, ref. no. 531 03
06-23, to the tank valve J.

3. Switch the pump to vacuum mode.

4. After pumping the indicator should be between
10-45 kPa.

Opening pressure inwards:

1. Open the tank lock and leave it open during the
entire test. Drain the fuel from the tank.

2. Loosen the positive pressure hose as
outlined in gure 54. Connect the pump,
ref. no. 531 03 06-23, to the tank valve J.

3. Switch the pump to pressure mode.

4. After pumping the indicator should stop at max.
7 kPa.

Fig 51

G
G

Fig 52

Fig 53

42 - English

Assembly

1. Thread the throttle cables in the connection M
as outlined in gure 55. NOTE! The gure is
shown from underneath.

2. Run the fuel hose D through hole K and hoses
B and C in hole L. See gure 55. Pull the hoses
so that the collars are on each side of the bot­tom on the carburettor compartment.

3. Tighten the chain catcher in place.

4. Press the movement limiter H into position. See
gure 53.

5. Tighten the screws F. See gure 51.

6. Hook on the throttle cable E in the intake bellow.
See gure 50.

7. Fit the tank unit. The two short screws are tted
to the bottom of the handle bar.

8. Assemble the carburettor as outlined in “Assem­bling the carburettor”. Assemble the air lter
and cylinder cover.

Repair Instructions

Fig 54

7.17 Vibration damping system

Dismantling

1. Dismantle the following parts:

• Bar and chain. See the Operator’s Manual.

• Cylinder cover. See the Operator’s Manual.

• Tank unit and handle. See “Dismantling the
tank unit”.

2. Dismantle the spring on the handle bar using a
4 mm Allen key (see gure 57).

3. Dismantle the springs on the tank unit using
a 4 mm Allen key (tool 502 50 18-01). See
gure 57.

Cleaning and inspection

Clean and inspect all parts.

Assembly

1. Fit the springs on the handle bar using a 4 mm
Allen key (tool 502 50 18-01).

Fig 55

Fig 56

2. Assemble the following parts:

• Tank unit and handle. See “Assembling the
tank unit”.

• Cylinder cover. See the Operator’s Manual.

• Bar and chain. See the Operator’s Manual.

Fig 57

English - 43

Repair Instructions

7.18 Replacing the fuel filter

NOTE!
Fluted pliers may not be used with the fuel

hose. They can cause material damage
resulting in damage to the fuel hose.

1

When replacing the fuel lter, the old fuel lter must
be taken out of the tank unit using special tool
502 50 83-01.

2

Pull out fuel hose B from the tank unit and pull
away the lter A. See gure 58.

3

Fit the new fuel lter A and press the
fuel hose back into place.

7.19 Replacing the fuel hose/return hose

The fuel hose is moulded and can only be removed
from outside of the fuel tank.

Use suitable pliers with a smooth cutting face and
loosen the hose B from the fuel tank. See gure 58.
Replace the return hose when required. Tighten
the fuel hose on the lter side with your ngers.

Fig 58

7.20 Replacing the fuel pump (Purge)

Dismantle

1. Dismantle the cylinder cover and the air lter.

2. Loosen suction hose C and return hose from
the fuel pump. See gure 59.

3. Snap off the fuel pump from the lter holder.

Assembling

1. Snap the fuel pump in place in the lter holder.
See gure 59.

2. Fit the return and suction hose on the fuel
pump.

3. Assemble the air lter and cylinder cover.

Fig 59

44 - English

7.21 Dismantling the piston and cylinder

1

Dismantle:

• The cylinder cover

• The carburettor (see “Dismantling the
carburettor”)

• The mufer

• The vibration element

• The spark plug cap

• The intake system

2

Unscrew the cylinder’s four screws
and carefully lift away the cylinder and the gasket.
See gure 60.

NOTE!
Take care to prevent any dirt and foreign

particles from entering the crankcase.

Repair Instructions

Fig 60

3

Cover over the crankcase opening.

4

Remove the circlips for the gudgeon pin and press
out the gudgeon pin. The lift off the piston. See
gure 61.

5

Remove the gudgeon pin bearing (the needle bear­ing) using a pliers. See gure 61. Replace with a
new bearing.

Cleaning and inspection of the cylinder

Clean all components, scrape off all gasket re­mains and soot from the following areas:

• The piston crown

• The top of the cylinder bore (inside)

• The cylinder exhaust port

• The base of the cylinder and/or crankcase

Fig 61

English - 45

Repair Instructions

Check the following:

• That the cylinder’s surface coating is not worn.
Especially the upper part of the cylinder.

• That the cylinder does not have any chafe or
cutting marks.

• That the piston is free of score marks. Minor
scratches can be polished off using ne emery
paper.

• That the piston ring is not burnt into its groove.

• Measure the wear on the piston ring. This must
not exceed 1 mm. See gure 62. Use the pis­ton to push the piston ring downward.

• That the gudgeon pin bearing is intact.

• That the intake bellows is intact.

• Pressure test the decompression valve. Carry
out pressure testing on the decompression
valve as follows. See also gure 68.

Fig 62

A. Fit the pressure gauge tool 531 03 06-23 to

the decompression valve.
B. Pump up the pressure to 80 kPa (0.8 bar).
C. Wait 30 seconds.
D. The pressure must not fall below 60 kPa

(0.6 bar).
Unscrew the cover plates for the carburettor and
mufer. Tighten the screws to the stated torque.
Remove the pressure test connection 503 84 40-02
and t the spark plug.

Fig 68

46 - English

Faults and causes
Score marks on the piston (A)

1. Leakage, check not carried out.

2. Too low octane fuel.

3. Too low or incorrect oil in the fuel.

Carbon build-up (B)

1. Too much or incorrect oil in the fuel.
See Figure 63.

Piston ring breakage

1. Piston ring worn out.

2. Oversized piston ring groove.

7.22 Assembling the piston and cylinder

Fig 63

A

Repair Instructions

B

1

Oil the gudgeon pin bearing with two-stroke oil and
insert it into the crank rod. See gure 64.

2

Replace the piston with the arrow facing the ex­haust port, and slide in the gudgeon pin and t the

circlips. NOTE! Use new circlips. See gure 64.

3

Oil the piston and piston ring with two-stroke oil.

4

Put a new cylinder base gasket in place. Compress
the piston ring and carefully push the piston into
the cylinder opening.

5

Attach the cylinder. The screws must be tightened
crosswise with a tightening torque of 8-10 Nm.

NOTE!
It is very important that the intake system is

sealed. Otherwise the engine may seize up.

Fig 64

Fig 65

English - 47

Repair Instructions

7.23 Pressure testing the cylinder

1

Loosen

• The cylinder cover

• The carburettor

2

Attach the cover plate 574 71 14-01 and plug
574 70 12-01. See gure 66.

3

Loosen the screws on the mufer and press the
cover plate 575 29 05-01 between the mufer and
cylinder. Tighten the screws for the mufer. See
gure 66. Use the plastic piston stop 575 29 36-01.

Fig 66a

4

Screw the pressure test connection 503 84 40-02
in place. Connect tool 531 03 06-23 to the nipple.

5

Pump the pressure up to 80 kPa (0.8 bar). Wait
30 seconds. The pressure should not be less than
60 kPa (0.6 bar). Remove the cover plates from
the silencer and carburettor, tighten the bolts to the
specied torque. Remove the pressure test nipplle­and ret the spark plug.

WARNING!
Once the cylinder has been
pressure tested, make sure the
inlet manifold is fitted correctly.
Otherwise the chainsaw can be
damaged.

Fig 66b

Fig 67

48 - English

Repair Instructions

7.24 Dismantling the crankshaft and
crankcase

1

Dismantle the following:

• The clutch cover

• The chain and bar.

• The centrifugal clutch *

• The cylinder cover

• The starter *

• The ywheel *

• The carburettor *

• The bottom of the carburettor *

• The hand guard *

• The mufer *

• The handle system *

• The fuel unit *

• The piston and cylinder *

• The ignition module

• Cabling

x4

Fig 69

• The oil pump

* See specic instruction.

NOTE!
Take care to prevent any dirt and foreign

particles from entering the bearings.

2.

If required, remove the circlip on the ywheel side.

3.

Remove the 5 screws from the pulley wheel side.
See Figure 69.

4.

Fit tool 575 28 69-01 as outlined in gure 70.
Remove the crankcase half on the clutch side.

5.

Fit tool575 28 69-01 as outlined in gure 71.
Remove the ywheel side’s crankcase half.

6.

Carefully pull the crankcase halves apart. Two
guide pins keep the crankcase halves together. Lift
out the connecting rod and dispose of the gasket.

Fig 70

WARNING!
Beware of burn injuries as the crankcase

halves are hot. Wear protective gloves.

Fig 71

English - 49

Repair Instructions

7.

If required, remove the crankshaft bearing from the
crankcase.
Proceed as follows:
A. Remove the oil rell cap.
B. Heat up the crankcase half in question to 200°C.
C. Use protective gloves. Press the bearing out of

the crankcase half.

8.

If the crankshaft bearings are still attached to the
crankshaft when dismantling, pull them off using
the 531 00 48-67 pulling device. See gure 73.
Also inspect the bearing grip in the crankcase half.

Cleaning and inspection

Fig 72

NOTE!
If the bearings are fitted to the crankcase,

take care to prevent any dirt and foreign
particles from entering.

Clean all parts and scrape off all gasket remains
from the contact surfaces on the crankcase halves.
Check the following:

1.

That the big-end bearing does not have any radial
play. Axial play is permitted. See gures 74 and 75.

2.

That the big-end bearing does not have any score
marks or is discoloured on the sides.

3.

That the bearing surface for the gudgeon pin bearing
does not have any score marks or is discoloured.

4.

That the crankshaft bearing has no play or knocks.

Fig 73

Fig 74

5.

That the sealing surfaces of the sealing rings tted
against the crankshaft are not worn, and that the
rubber is not hard.

6.

That the crankcase is not cracked.

50 - English

Fig 75

Assembly

WARNING!
Beware of burn injuries as the

crankcase halves are hot. Wear
protective gloves.

1

Proceed as follows if a bearing must be tted:
A. Heat up the crankcase half in question to 200°C.
B. Use protective gloves. Fit the bearing in the

ywheel side of the crankcase half. When tting
the bearing in the clutch side of the crankcase
half, the bearing must be tted aligned with the
inside of the crankcase.

C. Allow the crankcase half to cool down before

continuing with the work.

NOTE!
Take care to prevent any dirt and foreign

particles from entering the bearings.

Repair Instructions

Fig 76

D. Fit the oil rell cap.

2.

See page 52, gure 80, for how to t new sealing
rings.

NOTE!
Make sure the connecting rod is not crushed

against the crankcase when the crankcase
and crankshaft are fitted together.

3.

Use the 502 50 30-23 tool. Use the back end of
the sleeve and slot the crankshaft in place into the
clutch side of the crankcase half. See Figure 76.
Tighten until the crankshaft collar comes into con­tact with the bearing.

4.

Insert the guide pin in the crankcase half on the
clutch side, apply grease and t the gasket(C). See
Figure 77.

5

Use the 502 50 30-23 tool. Turn the sleeve and slot
the crankcase half in place on the ywheel side.
Tighten until the gasket is pinned in place between
the crankcase halves. See Figure 78.

6

Fit the screws. Tighten them alternately. Finally
tighten then to 8 Nm. See gure 79.

7

Fit the carburettor bottom with the four screws.
Tighten the screws using 5 Nm of torque. See
gure 79.

Fig 77

Fig 78

x4

NOTE!
Make sure that any excess gasket does

not finish up in the crankcase.

Fig 79

English - 51

Repair Instructions

8

Assemble the following parts:
A. Tank unit. See page 43.
B. Piston and cylinder. See page 47.
C. Mufer. See page 19.
D. Carburettor. See page 40.
E. Centrifugal clutch. See page 31.
F. Electrical System. See page 29.
G. Starter. See page 25.
H. Bar and chain. See the Operator’s Manual.

Sealing rings

1
To replace the crankshaft’s sealing rings, rst dis­mantle the following parts:
On the ywheel side:

• Starter. See page 25.

• Flywheel. See page 28.
On the clutch side:

• Bar and chain. See the Operator’s Manual.

• Chain guide plate. See page 17.

• Centrifugal clutch. See page 30.

• Oil pump. See page 31.

2

Use a screwdriver to remove the sealing ring and
pull it out.

3

Slide the dowel 575 34 69-01 (gure 80) on the
crankcase pin. Knock the new sealing ring in place
using the 575 34 70-01 tool. See Figure 81.

4

Fit the parts as outlined in point 1 above.

Fig 80

Fig 81

52 - English

7.25 Assembling a complete crankshaft

1

Fit the complete crankshaft in the crankcase.

Fit the following parts:

• The piston and cylinder *

• The fuel unit *

• The handle system *

• The mufer *

• The hand guard *

• The bottom of the carburettor *

• The carburettor *

• The ywheel *

• The starter *

• The cylinder cover

• The centrifugal clutch *

Repair Instructions

• The chain and bar.

• The clutch cover

* See specic instruction.

English - 53

Repair Instructions

7.26 Replacing the bar bolt

Replacing a bar bolt with intact crankcase

1

Empty the oil tank.

2

Knock in the old bar bolts from the outside so that
they end up in the oil tank.

3

Remove the bolts from the oil tank.

4

Attach a wire to the head of the bar bolt, lower the
wire through the oil tank and out through the bolt
opening in the crankcase. See gure 83.

5

Pull out the bar bolt so that it protrudes from its
opening. See gure 83.

Fig 83

6

Pull out the bar bolt with its nut. Insert a spacer
between the nut and the crankcase. See gure 83.

7

Fill with chain oil.

7.27 Repairing damaged threads

If threads on the chainsaw are worn, the repa­ration kit, 503 27 33-01, is available.

First drill with:

6.1 mm drill for the magnesium crankcase

Then screw in the thread plug using a suitable
screw and wrench.

This type of screw plug is ideal for plastic
and magnesium but cannot be used to repair
threads in aluminium. There is another type of
thread plug and metric screw available for this
purpose. See gure 84. Check the manufac­turer’s manual for thread information.

Fig 84

54 - English

English - 55

Troubleshooting

8 Troubleshooting

Contents

8.1 Troubleshooting ..............................................................................................................57

8.2 Troubleshooting methods ...............................................................................................58

56 - English

Troubleshooting

8.1 Troubleshooting

The different faults which may occur on the chain saw are divided into four groups. Within each group
possible operating faults are listed to the left while the probable fault alternatives are listed to the right.
The most likely fault is listed rst, etc. See separate instruction for Autotune troubleshooting.

Starting

Idling (low speed) (continued)

Difcult to start

The carburettor
leaks fuel

Floods when the
engine is not
running

Air lter blocked
Choke does not work
Worn choke axle
Worn choke valve
Blocked fuel lter
Blocked fuel line
Piston ring is stuck
Blocked impulse channel

Loose or faulty fuel pipe
Hole in diaphragm
Worn needle/needle tip
Control system sticking
Control system set too high
Leaking control system
(air or fuel)
The cover on the carburettor
pump side is loose

Worn needle/needle tip
Control system set too high
Control system sticking

Uneven idling

Worn needle/needle tip
Leaking diaphragm/cover plate
Worn lever arm in the control
system
Faulty diffuser jet

Blocked fuel lter
Blocked fuel line
Leaking inlet hose (rubber)
Loose carburettor mounting
Worn throttle valve axle
Loose throttle valve screw
Worn throttle valve
Leaking control system
(air or fuel)
The control system’s centre
knob is worn
Hole in diaphragm
Leaking diaphragm/
cover plate
Leaking crankcase

Idling (low speed)

Does not idle

Too rich idling

Leaking inlet hose (rubber)
Loose carburettor mounting
Loose or faulty fuel pipe
Blocked fuel lter
Blocked fuel line
Tank ventilator blocked
The throttle valve shaft is inert
Throttle stay is binding
Defective throttle return spring
Bent valve axle stop
Faulty diffuser jet

Worn needle/needle tip
Worn lever arm in the control
system
Leaking diaphragm/cover plate

Too much fuel at
idle speed

Blocked fuel line
Leaking control system
(air or fuel)
Leaking diaphragm/cover plate
Faulty diffuser jet
Leaking crankcase

Worn needle/needle tip
Leaking diaphragm/
cover plate

English - 57

Troubleshooting

High speed

Will not run
at full throttle

Low power

Will not “four
stroke”

Blocked air lter
Tank venting clogged
Blocked fuel lter
Blocked fuel line
Loose or faulty fuel pipe
Impulse channel leaking
Blocked impulse channel
The cover on the carburettor
pump side is loose
Faulty pump diaphragm
Leaking inlet hose (rubber)
Loose carburettor mounting
Control system set too low
Damaged control system
Control system incorrectly
assembled
Leaking diaphragm/cover plate
Control system sticking
Blocked mufer

Tank venting clogged
Blocked fuel lter
Impulse channel leaking
Blocked impulse channel
The cover on the carburettor
pump side is loose
Faulty pump diaphragm
Blocked air lter
Control system sticking
Leaking control system (air or
fuel)
Control system incorrectly
assembled
Loose diaphragm
Hole in diaphragm
Leaking diaphragm/cover plate

Tank venting clogged
Blocked fuel lter
Blocked fuel line
Loose or faulty fuel pipe
Impulse channel leaking
Blocked impulse channel
The cover on the carburettor
pump side is loose
Faulty pump diaphragm
Leaking inlet hose (rubber)
Loose carburettor mounting
Control system set too low
Leaking control system
(air or fuel)
Control system incorrectly
assembled
Loose diaphragm
Hole in diaphragm
Leaking diaphragm/cover plate

Acceleration and retardation

Does not
accelerate

The engine
stops when
releasing the
throttle

Blocked air lter
Tank venting clogged
Blocked fuel lter
Blocked fuel line
Loose or faulty fuel pipe
Blocked impulse channel
The cover on the carburettor
pump side is loose
Faulty pump diaphragm
Leaking inlet hose (rubber)
Loose carburettor mounting
Control system set too low
Control system incorrectly
assembled
Control system sticking
Faulty diffuser jet
Blocked mufer

Faulty pump diaphragm
Control system set too high
Control system sticking
Faulty diffuser jet

Blocked air lter
Faulty pump diaphragm
Faulty diffuser jet

8.2 Troubleshooting methods

In addition to faults given in the above schematic,
troubleshooting can be carried out on a specic
component or specic chain saw system. The
different procedures are described in respective
sections and are as follows:

• Function check of chain brake

• Resistance testing the stop plate

• Pressure testing the carburettor

• Pressure testing the decompression valve

• Pressure testing the cylinder

58 - English

• 115 26 56-26

2011W31