Winter Operation - Stihl MS 391 Safety Manual

Winter Operation

Remove shroud
N
Move the Master Control lever to the
stop position 0
N
Push the hand guard forwards – the
saw chain is blocked
2
1
N
Loosen screws (1)
N
Remove the shroud (2)
Pre-heat carburetor
At temperatures below +10 °C
1
N
Pull the slide (1) out of the
position s (summer operation)
MS 311, MS 391
N Place the slide in the position r
(winter operation) – r facing
upwards
N
Refit the shroud and tighten the
screws
Heated air is now drawn in from around
1
the cylinder and circulates around the
carburetor – this helps prevent
carburetor icing.
At temperatures above +20 °C
N
Ensure that the slide is set back to
position s (summer operation)
1
without fail, otherwise the engine
may malfunction due to overheating
At temperatures below -10 °C
Under extreme winter conditions
(temperatures below -10 °C, powdered
or drifting snow), it is recommended to
use the "cover plate mounting kit"
(special accessory).
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".
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!)
Cover plate
The cover plate (special accessory)
keeps out powdered or drifting snow.
When the cover plate is used, the slide
must be in the winter position.
If engine trouble occurs, first check
whether use of the cover plate is
necessary.
Attach cover plate
2
2
1
N
Insert cover plate (1) with both tabs
(arrows) and fasten with the
screws (2)
English
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