Husqvarna 120 Operator's Manual page 21

To do a check of the start/stop switch
1. Start the engine.
2. Push the start/stop switch to the STOP position. The
engine must stop. (Fig. 26)
To do a check of the muffler
WARNING: Do not use a product that has a
defective muffler or a muffler that is in bad
condition.
WARNING: Do not use a product if the spark
arrestor mesh on the muffler is missing or
defective.
1. Examine the muffler for damages and defects.
2. Make sure that the muffler is correctly attached to
the product. (Fig. 88)
3. If your product has a special spark arrestor mesh,
clean the spark arrestor mesh weekly. (Fig. 89)
4. Replace a damaged spark arrestor mesh.
CAUTION: If the spark arrestor mesh is
blocked, the product becomes too hot and
this causes damage to the cylinder and
piston.
To adjust the idle speed screw (T)
The basic carburetor adjustments are done at the
factory. You can adjust the idle speed but for more
adjustments, refer to your servicing dealer.
To give the components of the engine sufficient
lubrication during run-in, adjust the idle speed. Adjust
the idle speed to the recommended idle speed. Refer to
Technical data on page 26 .
CAUTION: If the saw chain rotates at idle
speed, turn the idle speed screw
counterclockwise until the saw chain stops.
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
to your servicing dealer. Do not use the
product until it is correctly adjusted.
1063 - 002 - 06.03.2019
To examine if the carburetor is correctly
adjusted
• Make sure that the product has the correct
acceleration capacity.
• Make sure that the saw chain does not rotate at idle
speed.
CAUTION: Incorrect adjustments 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. (Fig. 90)
3. Pull out the starter rope approximately 30 cm/12 in
and put it in the notch on the pulley.
4. Let the pulley rotate slowly rearward to release the
recoil spring. (Fig. 91)
5. Remove the center screw, the pulley (A) and the
recoil spring (B).
WARNING: You must be careful when
you replace the return spring or the
starter rope. The recoil spring is in
tension when it is wound up in the starter
housing. If you are not careful, it can
eject and cause injuries. Use protective
glasses and protective gloves.
6. Remove the used starter rope from the handle and
the pulley.
7. Attach a new starter rope to the pulley. Wind the
starter rope approximately 3 turns around the pulley.
8. Connect the pulley to the recoil spring. The end of
the recoil spring must engage in the pulley.
9. Assemble the recoil spring, the pulley and the center
screw.
10. Pull the starter rope through the hole in the starter
housing and the starter rope handle.
11. Make a tight knot at the end of the starter rope. (Fig.
92)
To tighten the recoil spring
1. Put the starter rope into the notch in the pulley.
2. Turn the starter pulley approximately 2 turns
clockwise.
3. Pull the starter rope handle and pull out the starter
rope fully.
4. Put your thumb on the pulley.
5. Move your thumb and release the starter rope.
6. Make sure that you can turn the pulley ½ turn after
the starter rope is fully extended. (Fig. 93)
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