Husqvarna 3120XP Manuel D'utilisation page 24

Carburetor adjustment
Because of environmental and emissions laws, your
product has adjustment limitations on the carburetor
adjuster screws. This decreases the harmful exhaust
fumes from your product. You can only turn the
adjustment screws maximum ½ turn.
Basic adjustments and run-in
The basic carburetor adjustments are done at the
factory. For the recommended idle speed, refer to
Technical data on page 34 .
CAUTION: Do not operate the product at too
high speed during the first 10 hours of
operation.
CAUTION: If the saw chain rotates at idle
speed, turn the idle speed screw
counterclockwise until the saw chain stops.
To adjust the low speed needle (L)
• Turn the low speed needle clockwise until stop.
Note: If the product has a bad acceleration capacity
or if the idle speed is not correct, turn the low speed
needle counterclockwise. Turn the low speed needle
until the acceleration capacity and idle speed is
correct.
To adjust the idle speed screw (T)
1. Start the product.
2. Turn the idle speed screw clockwise until the saw
chain starts to rotate.
3. Turn the idle speed screw counterclockwise until the
saw chain stops.
Note: The idle speed is correctly adjusted when the
engine runs correctly in all positions. The idle speed
must also be safely below the speed at which the saw
chain starts to rotate.
WARNING: If the saw chain does not stop
when you turn the idle speed screw, speak
24
To adjust the high speed needle (H)
The engine is adjusted at the factory to operate at sea
level. At higher altitudes, in different weather or different
temperatures it can be necessary to adjust the high
speed needle.
• Turn the high speed needle to make adjustments.
1/2
To examine if the carburetor is correctly
1/2
adjusted
• Make sure that the product has the correct
acceleration capacity.
• Make sure that the product 4-cycles a little at full
throttle.
• Make sure that the saw chain does not rotate at idle
speed.
• If the product is not easy to start or has less
acceleration capacity, adjust the low and high speed
needles.
To replace a broken or worn starter
rope
1. Loosen the screws to the starter housing
2. Remove the starter housing.
3. Pull out the starter rope approximately 30 cm/12 in
and put it in the notch on the pulley.
to your servicing dealer. Do not use the
product until it is correctly adjusted.
CAUTION: Do not turn the high speed
needle screw across the adjustment
limitation stop. This can cause damage
to the piston and the cylinder.
CAUTION: Incorrect adjustments can
cause damage to the engine.
1527 - 001 - 25.06.2020