Operating Instructions; Cleaning The Air Filter - Stihl FS 120 Instruction Manual

English
Dry the spark plug.
N
Open the throttle wide.
N
Crank the engine several times with
N
the starter to clear the combustion
chamber.
Refit the spark plug – see "Spark
N
Plug".
Move the slide control to START.
N
Set the choke knob to e – even if
N
the engine is cold.
Start the engine.
N
Throttle cable adjustment
Check adjustment of throttle cable –
N
see chapter on "Adjusting the
Throttle Cable".
Fuel tank run until completely dry
After refueling, press the fuel pump
N
bulb at least five times – even if the
bulb is filled with fuel.
Set the choke knob according to
N
engine temperature.
Start the engine.
N
34

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 periods – see "Storing the
Machine".

Cleaning the Air Filter

If there is a noticeable loss of engine
power
1
3
2
Turn the choke knob to g.
N
Press in the tab (1) and remove the
N
filter cover (2).
Clean away loose dirt from around
N
the filter (3) and inside the filter
cover.
Remove and check the filter
N
element – replace it if is dirty or
damaged.
Install the filter element in the filter
N
cover.
Refit the filter cover.
N
FS 120, FS 120 R, FS 200, FS 250, FS 250 R