Cleaning The Air Filter; Engine Management; Adjusting The Carburetor - Stihl KM 90 R Instruction Manual

Cleaning the Air Filter

If there is a noticeable loss of engine
power
4
Turn the choke knob to g
N
Take out the screw (1) and remove
N
the filter cover (2).
Clean away loose dirt from around
N
the filter.
Grip the filter element (3) at the
N
cutout (arrow) in the filter
housing (4) and remove it.
Fit a new filter element. As a
N
temporary measure you can knock it
out on the palm of your hand or blow
it out with compressed air. Do not
wash.
Replace damaged parts.
N
Installing the filter
Install the filter element in the filter
N
housing and fit the cover.
Insert the screw and tighten it down
N
firmly.
KM 90 R

Engine 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
major hardware.
1
2

Adjusting the Carburetor

The carburetor has been set at the
factory to provide an optimum fuel-air
mixture under most operating
conditions.
Adjusting Idle Speed
LA
Engine stops while idling
Warm up the engine for about
N
3 minutes.
Turn the idle speed screw (LA)
N
slowly clockwise until the engine
runs smoothly – the cutting
attachment must not rotate.
Cutting attachment rotates when engine
is idling
Turn the idle speed screw (LA)
N
counterclockwise until the cutting
attachment stops rotating and then
turn the screw about another 1/2 to
3/4 turn in the same direction.
WARNING
If the cutting attachment continues to run
when the engine is idling, have your
machine checked and repaired by your
servicing dealer.
English
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