MAINTENANCE
32 – English
High speed jet H
•The high speed jet H influences the power and engine
speed of the machine. If the high speed jet is set too
lean (H-jet screwed in too far) the machine will over-
rev and this will damage the engine. Run the machine
at full throttle for about 10 seconds. Then turn the H-
jet 1/4 turn anti-clockwise. Run the machine at full
throttle for another 10 seconds or so and listen to the
difference in the fast idle speed. Repeat this
procedure with the H-jet turned a further 1/4 turn anti-
clockwise.
• You have now run the machine at settings of H =±0,
H=+1/4, H=+1/2 relative to the basic settings. At full
throttle the engine has sounded different for each
setting. The H-jet is correctly adjusted when the
machine burbles a little. If the machine ”screams” then
the machine is set too lean. If the muffler emits a lot of
smoke and the machine burbles a lot then the setting
is too rich. Turn the H-jet clockwise until the setting
sounds right
CAUTION! To ensure correct adjustment you should enlist
a qualified mechanic who has access to a tachometer.
The recommended maximum fast idle speed must not be
exceeded.
Correctly adjusted carburettor
When the carburettor is correctly adjusted the machine
accelerates without hesitation and 4-cycles a little at full
throttle. It is also important that the chain does not rotate
at idle. If the L-jet is set too lean it may cause starting
difficulties and poor acceleration. If the H-jet is set too
lean the machine will have less power, poor acceleration
and could suffer damage to the engine.
If both the L and H jets are set too rich it will results in
acceleration problems or too low a working speed.
Checking, maintaining and
servicing chain saw safety
equipment
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.
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.
H
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.