Husqvarna Comprehensive Guide to 2 Stroke Carburetor Adjustment for Models

MAINTENANCE

Final setting of the idling speed T

Adjust the idling speed with the screw T, if it is necessary to readjust. First turn the idle speed adjusting screw T clockwise until the cutting attachment starts to rotate/ move.

Then turn, counter-clock- wise until the cutting attachment stops. A correctly adjusted idle speed setting occurs when the engine runs smoothly in every position. It should also be good margin to the rpm when the cutting attachment starts to rotate/move.

CAUTION! Contact your servicing dealer, if the idle speed setting cannot be adjusted so that the cutting attachment stops. Do not use the machine until it has been properly adjusted or repaired.

High speed needle
H
The high speed needle
affects the machine’s power,
speed, temperature and fuel
consumption. A too lean
adjustment on the high
speed needle H (the high
speed needle H is screwed in
too much) gives a too high
speed resulting in engine
damage. Do not allow the
engine to run at full speed
for more than 10 seconds.
Apply full throttle and turn
the high speed needle H
slowly anticlockwise until
the engine runs unevenly.
The high speed needle H is
then turned slowly
clockwise a little until the
engine runs smoothly.
Note the engine should be
run unloaded when	H
adjusting the high speed
needle.

Therefore dismantle the cutting equipment, nut, support flange and disc drive before adjusting the high speed needle. The high speed needle is adjusted correctly when the machine ‘splatters’ a little . If the machine smokes heavily at the same time as it ‘splatters’ heavily the adjustment is too rich.

NOTE! For optimum setting of the carburetor, contact a qualified servicing dealer who has a revolution counter at his disposal.

Correctly adjusted carburetor

A correctly adjusted carburetor means that the machine accelerates without hesitation and the machine 4-cycles a little at max speed. Furthermore, the cutting attachment must not rotate/move at idling. A too lean adjusted low speed needle L may cause starting difficulties and bad acceleration.

A too lean adjusted high speed needle H gives lower power

=less capacity, bad acceleration and/or damage to the engine.

A too rich adjustment of the two speed needles L and H gives acceleration problems or too low working speed.

18 – English