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If an incorrect spark plug is installed in a BR 600, the engine may quit after it warms
up, or it may run poorly. It may also try to run-on when the ignition is switched off.
;
Set the gap on all STIHL spark plugs at twenty thousands of an inch.
;
The final verification of a faulty ignition module may have to be done by replacing it
with a known good ignition module for comparison.
FS 90, FS 100, FS 110,
KM 110, FC 100, FC 110,
HT 100, HT 101 , HL 100
FS 130, KM 130,
HT 130, HT 131
BR 500, BR 550, BR 600
STIHL 0000 400 7009
Bosch USR7AC
NGK CMR5H
STIHL 0000 400 7011
NGK CMR6H
Refer to the STIHL repair specification charts for other models.
Air Filters
Air filters should be inspected and cleaned regularly. Filters should be replaced at least
once a year, or more often if needed.
;
The air filter element used on the
4-MIX®
shaft mounted engines should never be
cleaned in solvent. Brush off any loose debris and clean it with compressed air.
;
STIHL backpack blower engines use a pleated paper air filter. The only way to
service it is to brush off any debris or gently blow it off. Do not use high pressure
air or the pleats may tear.
;
Always inspect the clean side of the filter housing for any evidence of dirt or grit. If
dirt is present, the filter needs to be serviced more often.
Flywheel
Fault – A sheared flywheel key.
;
Occurs when: The nut is not properly tightened, or if an impact wrench is used to
loosen or tighten the fan wheel, flywheel, clutch, or starter cup nut.
;
A sheared key may not cause the ignition module to lose spark, so the spark tester
will not show a fault.
Key is sheared.
Never use an
impact wrench
on any STIHL
product!
Verify flywheel timing.