Instruction Manual

MS 231, MS 231 C, MS 251, MS 251 C
English
28
Heated air is now drawn in from around
the cylinder and circulates around the
carburetor – this helps prevent
carburetor icing.
At temperatures above +20 °C
N Ensure that the shutter is always
returned to position s (summer
operation), otherwise the engine
may malfunction due to overheating
At temperatures below -10 °C
N if the chain saw is extremely cold
(frost formation) – after starting,
bring the engine up to operating
temperature at increased idle speed
(disengage chain brake!)
In case of erratic idling behavior or poor
acceleration
N Turn the low speed screw (L)
1/4 turn counterclockwise
Whenever the low speed screw (L) has
been adjusted, it is usually also
necessary to adjust the idle speed
adjusting screw (LA), see "Setting the
carburetor".
Air filter system
N Retrofit new air filter if necessary –
see "Air filter system"
Positions of Master Control Lever
Stop 0 – engine off – the ignition is
switched off
Normal run position F – engine runs or
can fire.
Starting throttlen – this position is used
to start a warm engine. The Master
Control lever moves to the normal run
position as soon as the throttle trigger is
squeezed.
Choke shutter closed l – this position
is used to start a cold engine.
Setting the Master Control Lever
To move the Master Control lever from
the normal run position (F) to choke
closed (l), press down the throttle
trigger lockout and squeeze the throttle
trigger at the same time and hold them in
that position – now set the Master
Control lever.
To select the starting throttle
position (n), move the Master Control
lever to choke closed (l) first, then
push it into the starting throttle
position (n).
The Master Control lever must be in the
choke closed position (l) for the
changeover to the starting throttle
position (n).
The Master Control lever moves from
the starting throttle position (n) to the
run position (F) when you press down
the throttle trigger lockout and blip the
throttle trigger at the same time.
To switch off the engine, move the
Master Control lever to Stop (0).
Choke shutter closed (l)
– if the engine is cold
– if the engine stalls when you open
the throttle after starting.
– if the fuel tank was run until empty
(engine stopped).
Starting throttle position (n)
– if the engine is warm, i.e. if it has
been running for about one minute.
– When the engine begins to fire
– after clearing a flooded combustion
chamber.
Starting / Stopping the
Engine
STOP
0
001BA140 KN