FS 40, FS 40 C, FS 50, FS 50 C
English
22
N To correct a misalignment, turn the 
cap (with the grip up) until it drops 
fully into the tank opening.
N Twist the cap counterclockwise as 
far as it will go (approx. 1/4 turn) – 
this will twist the base of the cap into 
the correct position.
N Twist the cap clockwise, closing it 
normally – see the sections 
"Closing" and "Checking for proper 
closure."
N If your cap still does not tighten 
properly, it may be damaged or 
broken; immediately stop use of the 
unit and take it to your authorized 
STIHL dealer for repair.
Opening the threaded filler cap
N Turn the cap counterclockwise until 
it can be removed from the tank 
opening.
N Remove the filler cap.
Refueling
Take care not to spill fuel while fueling 
and do not overfill the tank.
Closing the threaded filler cap
N Position cap.
N Turn the cap clockwise as far as it 
will go and tighten it as securely as 
possible by hand.
Controls
Version with loop handle
1 Throttle trigger lockout
2 Throttle trigger
3 Stop switch with Run and 0 =Stop 
positions.
Function of stop switch and ignition 
system
The stop switch is normally in the Run 
position, i.e. when it is not depressed: 
The ignition is switched on – the engine 
is ready to start. If the stop switch is 
moved to the 0 position, the ignition is 
switched off. The ignition is switched on 
again automatically after the engine 
stops.
Left: Base of improperly aligned 
cap (with open space)
Right: Base of cap correctly posi-
tioned for installation
Starting / Stopping the 
Engine