Operating Instructions; Cleaning The Air Filter - Stihl FS 500 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 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".
FS 500, FS 550

Cleaning the Air Filter

If there is a noticeable loss of engine
power
5 3
4
N Turn the choke knob to g
N Loosen the screws (1).
N Remove the carburetor box
cover (2) with felt (3) and fabric (4)
filter elements.
N Clean away loose dirt from around
the filter and inside the filter cover.
N Remove the fabric and felt filter
elements from the filter cover.
N Knock out the fabric filter element or
blow it clear with compressed air.
If filter is caked with dirt:
N Wash the fabric filter in STIHL
unversal cleaner or a clean, non-
flammable solution (e.g. warm
soapy water) and then dry. Replace
damaged fabric filter element.
N Do not wash the felt filter – it may
only be knocked out or blown out.
Replace damaged or heavily
contaminated felt filter element.
N Pull out the air diverter (5), clean it
1
and reinstall.
N Fit felt and fabric filter elements in
the carburetor box cover.
N Fit the carburetor box cover.
2
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