STIHL 009, 010, 011 50
8.6.1 Notes for Fine Adjustment
of Carburetor
Adjusting idle speed screw
(Filter cover must be removed for this
adjustment)
Do not interchange these adjustment
screws!
Always carry out carburetor adjust-
ments with the engine warm and the
air filter clean.
Engine stops while idling:
Turn idle speed screw slightly clock-
wise (to the right) while the engine is
running (chain must not rotate).
Chain rotates at idle speed:
Turn idle speed screw slightly coun-
terclockwise (to the left).
Engine runs erratically at idle
speed:
Regulate at low-speed adjustment
screw. Turn clockwise for leaner mix-
ture or counterclockwise for richer
mixture.
Important: Even very slight
alteration of the adjustment screw
settings has a marked effect on
engine running characteristics.
The carburetor is adjusted at the fac-
tory to provide optimum engine
power and low fuel consumption
under local atmospheric conditions.
If the chain saw is operated at high
altitudes (mountains) or near sea
level, the carburetor setting must be
altered. This correction is made at
the two adjustments screws and the
idle speed screw.
Both adjustment screws must be very
carefully screwed down onto their
seats in order to obtain the basic set-
ting which is only intended as a guide
for fine adjustment. Then adjust as
follows:
High-speed adjustment screw H:
Long, open 1 turn
Low-speed adjustment screw L:
Short, open 1 turn
1 = High-speed adjustment screw
2 = Low-speed adjustment screw
3 = Idle speed screw