Adjusting The Carburetor; Spark Plug - Stihl FS 94 Instruction Manual

Adjusting the Carburetor

The carburetor of the machine has been
adjusted for optimum performance and
fuel efficiency in all operating states at
the factory.
Setting the idle speed
Engine stops when idling
Turn the idle speed adjusting
N
screw (LA) slowly clockwise until
the engine runs smoothly.
Cutting attachment turns when idling
Turn the idle speed adjusting
N
screw (LA) slowly counterclockwise
until the cutting attachment stops
turning
WARNING
If the cutting attachment continues to
keep rotating in idle even after
adjustment, have the machine checked
by a servicing dealer.
STIHL FS 94 R

Spark Plug

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
2
1
Turn screw (1) in cap (2) until cap
N
can be removed
Lay down cap
N
3
Unplug spark plug boot (3)
N
Unscrew spark plug
N
Checking the Spark Plug
Clean dirty spark plug.
N
Check electrode gap (A) and
N
readjust if necessary – see chapter
"Specifications."
Use only resistor type spark plugs of
N
the approved range.
Rectify problems which have caused
fouling of spark plug:
too much oil in fuel mix,
–
dirty air filter,
–
unfavorable running conditions, e.g.
–
operating at part load.
English
A
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