Winter Operation - Stihl MS 250 Instruction Manual

felling cut. The chain brake will operate
only if it has been properly maintained
and the hand guard has not been
modified in any way.
Check operation of chain brake
Before starting work: Run engine at idle
speed, engage the chain brake (push
hand guard toward bar nose).
Accelerate up to full throttle for no more
than 3 seconds – the chain must not
rotate. The hand guard must be free
from dirt and move freely.
Chain brake maintenance
The chain brake is subject to normal
wear. It is necessary to have it serviced
and maintained regularly by trained
personnel, such as your STIHL servicing
dealer, at the following intervals:
Full-time usage:
Part-time usage:
Occasional usage:
MS 250

Winter Operation

At temperatures below +50°F (+10°C):
Squeeze the throttle trigger lockout
N
and move the Master Control lever
to l (cold start).
Turn the knob above the rear handle
N
every 3
90° counterclockwise.
months
Lift off the carburetor box cover
N
every 6
vertically.
months
every 12
months
Lift out the shutter (in front of spark
N
plug) vertically.
Turn the shutter 180°.
N
Refit the shutter.
N
Refit the carburetor box cover and
N
secure it with the knob.
Heated air is now drawn in from around
the cylinder to warm the carburetor – this
helps prevent carburetor icing.
NOTICE
At temperatures above +70 °F (+ 20°C),
always close the shutter again. This is
necessary to avoid engine running
problems and overheating.
English
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