Checking, maintaining and
servicing chain saw safety
equipment
Note! All service and repair work on the machine
demands special training. This is especially true of the
machine's safety equipment. If your machine fails any
of the checks described below we recommend that you
take it to your service workshop. Any maintenance
other than that described in this manual must be
carried out by your servicing dealer (retailer).
Switch off the engine and take off the ignition cable
before repairs or maintenance
Chain brake and front hand guard
Checking brake band wear
Brush off any wood dust, resin and dirt from the chain
brake and clutch drum. Dirt and wear can impair operation
of the brake. (46)
Regularly check that the brake band is at least 0.6 mm
thick at its thinnest point.
Checking the front hand guard
Make sure the front hand guard is not damaged and that
there are no visible defects such as cracks.
Move the front hand guard forwards and back to make sure
it moves freely and that it is securely anchored to the clutch
cover. (47)
Checking the inertia brake release
Place the chain saw, with the engine switched off, on a
stump or other stable surface. Release the front handle
and let the saw fall by its own weight, rotating around the
rear handle towards the stump.
When the bar hits the stump the brake should be
applied. (48)
Checking the brake trigger
Place the chain saw on firm ground and start it. Make sure
the chain does not touch the ground or any other object.
See the instructions under the heading Start and stop.
Grasp the chain saw firmly, wrapping your fingers and
thumbs around the handles.
Apply full throttle and activate the chain brake by tilting your
left wrist forward onto the front hand guard. Do not let go of
the front handle. The chain should stop immediately.
Throttle lockout
• Make sure the throttle control is locked at the idle setting
when the throttle lockout is released.
• Press the throttle lockout and make sure it returns to its
original position when you release it.
• Check that the throttle control and throttle lockout move
freely and that the return springs work properly.
• Start the chain saw and apply full throttle. Release the
throttle control and check that the chain stops and
remains stationary. If the chain rotates when the throttle
control is in the idle position you should check the
carburettor idle adjustment.
Chain catcher
Check that the chain catcher is not damaged and is firmly
attached to the body of the chain saw.
20 – English
MAINTENANCE
Right hand guard
Check that the right hand guard is not damaged and that
there are no visible defects, such as cracks.
Vibration damping system
Regularly check the vibration damping units for cracks or
deformation.
Make sure the vibration damping units are securely
attached to the engine unit and handle unit.
Stop switch
Start the engine and make sure the engine stops when you
move the stop switch to the stop setting.
Muffler
Never use a machine that has a faulty muffler. Regularly
check that the muffler is securely attached to the machine.
Note: The spark arrestor screen (A) on this machine is
serviceable. (49) The mesh must be replaced if it is
damaged. If the mesh is blocked the machine will overheat
and this will cause damage to the cylinder and piston.
Never use a machine with a muffler that is in poor
condition. Never use a muffler if the spark arrestor
mesh is missing or defective.
For normal homeowner use, the muffler and spark
arresting screen will not require replacement. After 75
hours of use, we recommend that your muffler be replaced
by your authorized Husqvarna service dealer.
Air filter
The air filter must be regularly cleaned to remove dust and
dirt in order to avoid:
• Carburettor malfunctions
• Starting problems
• Loss of engine power
• Unnecessary wear to engine parts.
• Excessive fuel consumption.
• Remove the air filter (3) after taking off the cylinder
cover, screw (1) and filter cover (2). When refitting make
sure that the air filter seals tightly against the filter
holder. Clean the filter by brushing or shaking it. (50)
The filter can be cleaned more thoroughly by washing it in
water and detergent.
An air filter that has been in use for a long time cannot be
cleaned completely. The filter must therefore be replaced
with a new one at regular intervals. A damaged air filter
must always be replaced.
A HUSQVARNA chain saw can be equipped with different
types of air filter according to working conditions, weather,
season, etc. Contact your dealer for advice.
Spark plug
The spark plug condition is influenced by:
• Incorrect carburettor adjustment.
• An incorrect fuel mixture (too much or incorrect type of oil).
• A dirty air filter.
These factors cause deposits on the spark plug electrodes,
which may result in operating problems and starting
difficulties.
If the machine is low on power, difficult to start or runs
poorly at idle speed: always check the spark plug first
before taking any further action. If the spark plug is dirty,
clean it and check that the electrode gap is 0.5 mm. The
spark plug should be replaced after about a month in
operation or earlier if necessary.
Note! Always use the recommended spark plug type! Use
of the wrong spark plug can damage the piston/cylinder.
Check that the spark plug is fitted with a suppressor.
5451676-47 Rev. 4 2008-08-08