English
Air Filter System
The air filter system can be adapted to
suit different operating conditions by
installing different filters. Changing the
filter is quick and simple.
Fleece filter
N
Fleece filter for normal operating
conditions and dry work areas.
HD2 filter
N
HD2 filter (black filter frame, pleated
filter material) for extreme wintry
conditions (e.g. powder or drifting
snow) or very dusty work areas.
40
Cleaning the Air Filter
If there is a noticeable loss of engine
power
N
Remove the shroud – see "Shroud"
Remove air filter
N
Clean away loose dirt from around
the filter
Do not use tools to remove and
install the air filter – the air filter
could be damaged in the process.
1.
2.
N
Turn air filter 1/4 turn
counterclockwise and remove in the
direction of the rear handle
N
Always replace a damaged filter
Cleaning the air filter
N
Knock out the filter or blow it clear
with compressed air from the inside
outwards
In case of stubborn dirt or stuck filter
fabric
N
Wash the filter in STIHL special-
purpose cleaner (special
accessory) or a clean, non-
flammable cleaning liquid (e. g.,
warm soapy water) – rinse the filter
from inside to out under a water jet
– do not use high-pressure cleaners
N
Dry all filter parts – do not expose to
extreme heat
Installing the air filter
1.
2.
N
Fit air filter
N
Press the air filter in the direction of
the filter housing and
simultaneously turn it clockwise
until the air filter engages – the
"STIHL" logo must be horizontal
N
Fit the shroud – see "Shroud"
MS 291 C-Q