Husqvarna 543 XP Operator's Manual page 25

Carburetor with adjustment limitations
Note:
If you do not know which carburetor type that
you have on your product, speak to your servicing
dealer.
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:
at too high speed during the first 10 hours of
operation.
CAUTION:
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.
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Do not operate the product
If the saw chain rotates
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:
stop when you turn the idle speed screw,
speak to your servicing dealer. Do not use
the product until it is correctly adjusted.
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.
CAUTION:
high speed needle screw across the
adjustment limitation stop. This can
cause damage to the piston and the
cylinder.
To examine if the carburetor is correctly
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.
CAUTION:
can cause damage to the engine.
To replace a broken or worn starter
rope
1. Loosen the screws to the starter housing.
2. Remove the starter housing.
If the saw chain does not
Do not turn the
Incorrect adjustments
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