Checking, Maintaining And Servicing Chain Saw Safety Equipment - Husqvarna 288XP Operator's Manual

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 rich
(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.
H
• 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! For optimum adjustment of the carburettor,
contact a qualified dealer/service workshop that has a
revolution counter at their disposal. 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 burbles 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 the L and H-jets are set too rich it will
lead to acceleration problems or too low a working speed.
MAINTENANCE
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.
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.
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English