Spark Plug; Lubricating The Bar Tip Sprocket; Adjustment Of The Oil Pump; Cooling System - Husqvarna 439 Operator's Manual

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:
• 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 0.65 mm.
0,65
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.

Lubricating the bar tip sprocket

Lubricate the bar tip sprocket each time you refuel. Use
the special grease gun and a good quality bearing grease.
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MAINTENANCE

Adjustment of the oil pump.

The oil pump is adjustable. Adjustments are made by
turning the screw using a screwdriver. The machine is
supplied from the factory with the screw set to middle
position. Turning the screw clockwise will reduce the oil
flow and turning the screw anti-clockwise will increase the
oil flow.
!

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 Air guide plate.
3 Fins on the flywheel.
4 Cooling fins on the cylinder.
5 Clutch cover
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.
WARNING! The engine must not be
running when making adjustments.
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