Instruction Manual

MS 171, MS 181, MS 181 C, MS 211, MS 211 C
English
47
Adjusting Idle Speed
N Carry out the standard setting.
N Start and warm up the engine.
Engine stops while idling
N Turn the idle speed screw (LA)
clockwise until the chain begins to
run – then back it off 2 turns.
Saw chain runs while engine is idling
N Turn the idle speed screw (LA)
counterclockwise until the chain
stops moving – then turn it another
2 turns 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.
Erratic idling behavior, poor acceleration
(even though standard setting of low
speed screw is correct)
Idle setting is too lean
N Turn the low speed screw (L)
carefully counterclockwise, no
further than stop, until the engine
runs smoothly and accelerates well.
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 the standard setting.
N Warm up the engine.
N Turn high speed screw (H) slightly
clockwise (leaner) – no further than
stop.
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.
Spark arresting screen in muffler
WARNING
To reduce the risk of fire caused by hot
particles escaping from the machine,
never operate the machine without a
spark arresting screen, or with the spark
arresting screen damaged. Do not
modify the muffler or spark arresting
screen. To reduce the risk of fire from
accumulated debris such as pine
needles, branches or leaves, ensure
that the muffler plugs are in place before
taking up work.
NOTICE
According to the law or regulations in
some countries or federal states, certain
operations may only be carried out if a
properly serviced spark arresting screen
is provided.
N If the engine is down on power,
check the spark arresting screen in
the muffler.
N If the muffler plugs are missing or
damaged, mount new plugs.
STIHL recommends that maintenance
and repair work be carried out only by
authorized STIHL dealers.
LA
L
533BA021 KN
Spark Arresting Screen in
Muffler