► Turn the knob above the rear handle in the
direction of the arrow and remove the carbu‐
retor box cover
145BA028 K
► Remove filter
22 Cleaning the Air Filter
If there is a noticeable loss of engine power:
► Wash the filter in STIHL special-purpose
cleaner (special accessory) or a clean, non-
flammable cleaning liquid (e.g., warm soapy
water) – rinse the filter from inside to out under
a water jet – do not use high-pressure clean‐
ers
► Dry all filter parts – do not expose to extreme
heat
► Do not oil the filter
► Reinstall filter
23 Adjusting the Carburetor
23.1
General Information
The carburetor comes from the factory with a
standard setting.
This setting provides an optimum fuel-air mixture
under most operating conditions.
With this carburetor it is only possible to correct
the adjusting screws within fine limits.
23.2
Standard Setting
► Shut off the engine.
► Check the air filter and clean or replace if nec‐
essary.
► Check the spark arresting screen (not in all
models, country-specific) in the muffler and
clean or replace if necessary.
L
H
171BA019 KN
L
H
1/2
1/4
► Turn high speed screw (H) counterclockwise
as far as stop (no more than 1/2 turn).
► Turn the low speed screw (L) clockwise as far
as stop, then turn it back 1/4 turn.
23.3
Adjusting Idle Speed
► Carry out the standard setting.
► Start and warm up the engine.
L
LA
171BA020 KN
L
H
1/2
1/4
23.3.1
Engine stops while idling
► Set the low speed screw (L) to 1/4 turn open.
► Turn the idle speed screw (LA) clockwise until
the chain begins to run – then back it off
1/4 turn.
23.3.2
Saw chain runs while engine is idling
► Set the low speed screw (L) to 1/4 turn open.
► Turn the idle speed screw (LA) counterclock‐
wise until the chain stops moving – then turn it
another 1/4 turn in the same direction.
WARNING
If the chain continues moving when the engine is
idling, have your saw checked and repaired by
your servicing dealer.
23.3.3
Erratic idling behavior, poor accelera‐
tion (even though low speed screw is
open 1/4 turn)
Idle setting is too lean
► Turn the low speed screw (L) counterclock‐
wise, no further than stop, until the engine
runs and accelerates smoothly.
English
22 Cleaning the Air Filter
30
0458-550-0121-B