Stihl FS 250 User Manual

FS 120, FS 120 R, FS 250
English
32
Cutting attachment rotates when engine
is idling
N Turn the idle speed screw (LA)
counterclockwise until the cutting
attachment stops moving and then
turn the screw another 1/2 to 1 full
turn in the same direction.
WARNING
If the cutting attachment continues to
rotate when the engine is idling, have
your machine checked and repaired by
your servicing dealer.
Erratic idling behavior, poor acceleration
(even though setting of LA screw is
correct).
Idle setting is too lean
N Turn the low speed screw (L)
counterclockwise, no more than 1/2
turn, until the engine runs and
accelerates smoothly.
Erratic idling behavior
Idle setting is too rich
N Turn the low speed screw (L)
clockwise, no more than 1/2 turn,
until the engine runs and
accelerates smoothly.
It is usually necessary to change the
setting of the idle speed screw (LA) after
every correction to the low speed
screw (L).
Fine Tuning for Operation at High
Altitude
A slight correction of the setting may be
necessary if the engine does not run
satisfactorily:
N Carry out standard setting.
N Warm up the engine.
N Turn high speed screw (H) slightly
clockwise (leaner) – no more than a
3/4 turn.
NOTICE
After returning from high altitude, reset
the carburetor to the standard setting.
If the setting is too lean there is a risk of
engine damage due to insufficient
lubrication and overheating.
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 Turn off the engine.
N Pull off the spark plug boot (1).
N Unscrew the spark plug.
Spark Plug
250BA054 KN

Stihl FS 250 Specifications

General

Brand	Stihl
Model	FS 250
Category	Trimmer
Language	English