Instruction Manual
MS 311, MS 391
English
40
If there is a noticeable loss of engine
power
Removing the shroud
N Move the Master Control lever to the
stop position (0).
N Push the hand guard forward – the
chain is locked.
N Open the twist locks (1) by turning
them 1/4 turn counterclockwise with
the combination wrench.
N Remove the shroud (2).
Removing the air filter
N Clean away loose dirt from around
the filter.
NOTICE
To avoid damaging the filter, do not use
tools for removing and installing the air
filter.
N Rotate the air filter a 1/4 turn
counterclockwise and lift it away in
the direction of the rear handle.
N Always replace a damaged filter.
Cleaning the air filter
N Wash the filter in STIHL special
cleaner (special accessory) or a
clean, non-flammable solution (e.g.
warm soapy water). Rinse the filter
from the inside outwards under a jet
of water – do not use a pressure
washer.
N Dry the filter components – do not
expose to high temperatures.
N Do not impregnate the filter with oil.
N Reinstall the air filter.
Installing the air filter
N Place the air filter in position.
N Push the air filter in the direction of
the filter housing and turn it
clockwise at the same time until it
engages – the "STIHL" name must
be horizontal.
N Install the shroud.
Cleaning the Air Filter
1
4903BA002 KN
1
1
2
1.
2710BA000 KN
2.
2710BA001 KN
2.
1.