Instruction manual

FS 55, FS 55 C, FS 55 R, FS 55 RC
English
28
N If the engine is down on power,
difficult to start or runs poorly at idle
speed, first check the spark plug.
N Fit a new spark plug after about 100
operating hours – or sooner if the
electrodes are badly eroded. Install
only suppressed spark plugs of the
type approved by STIHL – see
"Specifications".
Removing the Spark Plug
N Move the stop switch to 0.
N Pull off the spark plug boot (1).
N Unscrew the spark plug.
Checking the spark plug
N Clean dirty spark plug.
N Check electrode gap (A) and
readjust if necessary – see
"Specifications".
N Rectify the problems which have
caused fouling of the spark plug.
Possible causes are:
– Too much oil in fuel mix.
– Dirty air filter.
– Unfavorable running conditions.
Installing the spark plug
N Screw home the spark plug, fit the
boot and press it down firmly.
Spark Plug
1
232BA081 KN
If the spark plug comes with a
detachable adapter nut (1), screw
the adapter onto the thread and
tighten it down firmly to reduce
the risk of arcing and fire.
000BA039 KN
A
1
000BA045 KN