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FS 40, FS 40 C, FS 50, FS 50 C
English
26
The carburetor has been set at the
factory to provide an optimum fuel-air
mixture under most operating
conditions.
Adjusting Idle Speed
Engine stops while idling
N
Warm up the engine for about
3 minutes.
N
Turn the idle speed screw (LA)
slowly clockwise until the engine
runs smoothly – the cutting
attachment must not run.
Cutting attachment runs when engine is
idling
N
Turn the idle speed screw (LA)
counterclockwise until the cutting
attachment stops moving and then
rotate the screw another 1/2 to 3/4
turn in the same direction.
WARNING
If the cutting attachment continues to run
when the engine is idling, have your
machine checked and repaired by your
servicing dealer.
If engine is down on power, difficult to
start or runs poorly at idling speed, first
check the spark plug.
Fit a new spark plug after approx. 100
operating hours or earlier if the
electrodes are badly eroded.
Wrong fuel mix (too much engine oil in
the gasoline), a dirty air filter and
unfavorable running conditions (mostly
at part throttle etc.) affect the condition
of the spark plug. These factors cause
deposits to form on the insulator nose
which may result in trouble in operation.
Removing the Spark Plug
N
Shut off the engine.
N
Remove the spark plug boot (1).
N
Unscrew the spark plug (2).
Checking the Spark Plug
N
Clean dirty spark plug.
N
Check electrode gap (A) and
readjust if necessary – see
"Specifications."
N
Use only resistor type spark plugs of
the approved range.
Rectify problems that have caused
fouling of spark plug:
–
too much oil in fuel mix,
–
dirty air filter,
–
unfavorable running conditions, e.g.
operating at part load.
Adjusting the Carburetor
0815BA006 KN
Spark Plug
1
547BA041 KN
2
000BA039 KN
A