Operating Instructions; Cleaning The Air Filter; Motor Management - Stihl KM 90 Instruction Manual

Operating Instructions

During break-in period
A factory new machine should not be run
at high revs (full throttle off load) for the
first three tank fillings. This avoids
unnecessary high loads during the
break-in period. As all moving parts
have to bed in during the break-in
period, the frictional resistances in the
engine are greater during this period.
The engine develops its maximum
power after about 5 to 15 tank fillings.
During operation
After a long period of full-throttle
operation, allow engine to run for a while
at idle speed so that the heat in the
engine can be dissipated by flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After finishing work
Storing for short period:
Wait for engine to cool down. To avoid
condensation, fill the fuel tank and keep
the unit in a dry place until you need it
again. Storing for a long period:
see chapter "Storing the Machine".
KM 90, KM 90 R

Cleaning the Air Filter

4
Dirty air filters reduce engine power,
increase fuel consumption and make
starting more difficult.
If there is a noticeable loss of engine
power:
: Set the choke knob to g.
: Take out the screw (1) and remove
the filter cover (2).
: Clean away loose dirt from around
the filter.
: Grip the filter element (3) at the
notch (arrow) in the filter housing (4)
and take it out.
: Fit a new filter element. As a
temporary measure you can knock it
out on the palm of your hand or blow
it out. Do not wash.
: Replace any damaged parts.
: Install filter element in the filter
housing.
: Refit the filter cover.
: Insert the screw and tighten it down
firmly.

Motor Management

Exhaust emissions are controlled by the
design of the fundamental engine
parameters and components (e.g.
carburation, ignition, timing and valve or
port timing) without the addition of any
1
major hardware.
2
English
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