Husqvarna 1153179-26 Benutzerhandbuch

English

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Place the machine on a flat surface so that the bar 
points away from you and so that the bar and chain do 
not come into contact with the surface or other 
objects.

Turn the low speed jet L clockwise until it stops. If the 
engine accelerates poorly or idles unevenly, turn the low 
speed jet L anticlockwise until good acceleration and 
idling are achieved.

Adjust the idle speed with the T-screw. If it is necessary to 
re-adjust, turn the T-screw clockwise while the engine is 
running, until the chain starts to rotate. Then turn anti-
clockwise until the chain stops. When the idle speed is 
correctly adjusted the engine should run smoothly in 
every position and the engine speed should be safely 
below the speed at which the chain starts to rotate.

At the factory the engine is adjusted at sea level. 
When working at a high altitude or in different 
weather conditions, temperatures and atmospheric 
humidity, it may be necessary to make minor 
adjustments to the high speed jet.
CAUTION!  If the high speed jet is screwed in too far, 
it may damage the piston/cylinder.
When test run at the factory, the high speed jet is set so that 
the engine satisfies the applicable legal requirements at the 
same time as achieving maximum performance. The 
carburettor’s high speed jet is then locked using a limiter cap 
in the fully screwed out position. The limiter cap limits the 
potential to adjust the high speed jet to at most half a turn.

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.

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The carburettor governs the engine’s speed via the 
throttle control. Air and fuel are mixed in the 
carburettor. The air/fuel mixture is adjustable. Correct 
adjustment is essential to get the best performance 
from the machine.

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The satisfactory operation of a catalytic converter 
depends, among other factors, on the correct 
adjustment of the carburettor. Carefully follow the 
instructions below, using a tachometer as an aid.

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Adjusting the carburettor means that the engine is 
adapted to local operating conditions, e.g. climate, 
altitude, petrol and the type of 2-stroke oil.

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The carburettor has three adjustment controls:

   - L = Low speed jet
   - H = High speed jet
   - T = Idle adjustment screw

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The L and H-jets are used to adjust the supply of fuel 
to match the rate that air is admitted, which is 
controlled with the throttle. If they are screwed 
clockwise the air/fuel ratio becomes leaner (less fuel) 
and if they are turned anti-clockwise the ratio 
becomes richer (more fuel). A lean mixture gives a 
higher engine speed and a rich mixture gives a lower 
engine speed.

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The T-screw regulates the throttle setting at idle 
speed. If the T-screw is turned clockwise this gives a 
higher idle speed; turning it anti-clockwise gives a 
lower idle speed.

The basic carburettor settings are adjusted during testing 
at the factory.

The basic settings are H = 1 turn and L = 1 turn. To 
provide the engine’s components with good initial 
lubrication (during running in) the carburettor should be 
set for a richer fuel mixture for the first 3-4 hours that the 
chain saw is in use. To do this, adjust the fast idle speed 
to 600-700 rpm below the recommended maximum fast 
idle speed.

If you are unable to check the fast idle speed using a 
tachometer the H-jet should not be set for a leaner mixture 
than given in the basic settings. The recommended 
maximum fast idle speed must not be exceeded.

CAUTION!  If the chain rotates while idling the T-screw 
must be turned anti-clockwise until the chain stops.

Rec. idle speed: 2700 rpm