20 – English
MAINTENANCE
Cooling system
To keep the working temperature as low as possible the
machine is equipped with a cooling system.
The cooling system consists of:
1 Air intake on the starter.
2 Fins on the flywheel.
3 Cooling fins on the cylinder.
4 Cylinder cover (directs cold air over the cylinder).
Clean the cooling system with a brush once a week, more
often in demanding conditions. A dirty or blocked cooling
system results in the machine overheating which causes
damage to the piston and cylinder.
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.
CAUTION! 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.
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.
Clean the filter every 25 hours, or more regularly if conditions
are exceptionally dusty.

Cleaning the air filter

Remove the air filter cover and take out the filter. Wash it
clean in warm, soapy water. Ensure that the filter is dry before
refitting it.
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.
If the machine is used in dusty conditions the air filter should
be soaked in oil. See instructions under the heading Oiling the
air filter.

Oiling the air filter

Always use HUSQVARNA filter oil, art. no. 531 00 92-48. The
filter oil contains a solvent to make it spread evenly through
the filter. You should therefore avoid skin contact.
Put the filter in a plastic bag and pour the filter oil over it.
Knead the plastic bag to distribute the oil. Squeeze the
excess oil out of the filter inside the plastic bag and pour off
the excess before fitting the filter to the machine. Never use
common engine oil. This would drain through the filter quite
quickly and collect in the bottom.
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