Adjusting The Carburetor - Stihl MM 55 Manual De Instrucciones

English / USA

Adjusting the carburetor

The carburetor is set to the basic setting
at the factory.
This carburetor setting ensures that an
optimum fuel-air mixture is delivered to
the engine under all operating
conditions.
With this carburetor, the setting can only
be adjusted within limits via the high
speed adjusting screw.
20
Standard setting
: Switch off engine
: Fit MultiTool
: Check air filter – replace if
necessary
: Turn high speed adjusting screw (H)
counterclockwise as far as
possible – max. 3/4 turn
: Carefully screw the low speed
adjusting screw (L) clockwise down
onto its seat, then back off one turn
counterclockwise
: Start the engine and let it warm up
: Now adjust the idling speed with the
idle speed adjusting screw (LA) so
that the tool does not move
Setting for use at high altitudes or
sea level
If the engine performance is
unsatisfactory when working in
mountainous country or at sea level, it
may be necessary to marginally adjust
the setting of the high speed adjusting
screw (H).
: Carry out standard setting
: Let engine warm up for approx.
3 minutes at full throttle
Rough guide
The high speed adjusting screw
must be turned through roughly
1/4 turn for every 1000 m (3300 ft)
difference in altitude.
In mountainous country
: Turn the high speed adjusting
screw (H) clockwise (leaner) – up to
the stop at most
At sea level
: Turn the high speed adjusting
screw (H) counterclockwise
(richer) – up to the stop at most
Normally, the maximum speed will
already be achieved at the standard
setting.
MM 55, MM 55 C