Husqvarna FR335, Workshop Manual

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10
2
Electrical system
502 51 91-01
502 71 13-01
333/335
336
The engine is equipped with an electronic ignition system completely without moving parts. Consequently, a
faulty component cannot be repaired, but must be replaced by a new component.
The spark in an electronic ignition system has a very short burn time and can therefore be interpreted as
weak and can be diffi
cult to see while troubleshooting.
Make sure the stop switch is in the start
position (333/335).
Earth the spark plug on the cylinder
(333/335) or earth it using a steel wire
around a starter screw that is screwed
to the crankcase (336).
Give a sharp pull on the starter handle.
A spark should be seen between the
electrodes.
If no spark is seen test with test spark
plug no. 502 71 13-01.
If a spark then occurs, the spark plug is
faulty.
Try a new spark plug.
Checking the ignition
spark
Clean the electrodes and check the
electrode gap.
Checking the ignition
spark
Remove the spark plug and clean it from
soot deposits with the help of a steel
brush.
Check the electrode gap. It should be
0.5 mm.
Adjust the gap as needed to the correct
value with the side electrode.
If the electrodes are worn more than
50% the spark plug should be changed. If the electrodes are worn more than
50% the spark plug should be changed.
Too large a spark gap entails a great
deal of stress on the ignition module and
risk for short-circuiting.