Operating Instructions; Cleaning The Air Filter - Stihl HL 90 Instruction Manual

English
N Open the throttle wide.
N Crank the engine several times with
the starter to clear the combustion
chamber.
N Refit the spark plug.
N Connect the spark plug boot (press
it down firmly).
N Move the slide control to START.
N Set the choke knob to e – even if
the engine is cold.
N Now start the engine.
Throttle cable adjustment
N Check adjustment of throttle cable –
see chapter on "Adjusting the
Throttle Cable".
If fuel tank has been run completely
dry and then refueled
N
Press the fuel pump bulb at least
five times – even if the bulb is filled
with fuel.
N Set the choke knob according to
engine temperature.
N Now start the engine.
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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 the engine to run for a
short while at idle speed so that engine
heat can be dissipated by the flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After Finishing Work
Storing for a short period: Wait for the
engine to cool down. Empty the fuel tank
and keep the machine in a dry place,
well away from sources of ignition, until
you need it again. For longer out-of-
service perionds – see "Storing the
Machine".

Cleaning the Air Filter

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