Briggs & Stratton 21000 Series Operating & Maintenance Instructions page 14

Cleaning Debris
Daily or before every use, clean accumulated debris
from engine. Keep linkage, spring and controls clean.
Keep area behind muffler free of any combustible
debris.
Spark Plug
Check the spark plug every 50 hours. Replace the
spark plug if upon inspection the electrode is burned or
worn. Ensure the spark plug is clean. Check the gap
with a feeler gauge and reset if necessary. Use only
Briggs & Stratton Spark Tester (part number 19368) to
check for spark.
Champion style plug ............. set gap at 0.025 in.
NGK style plug ............ set gap at 0.020-0.024 in.
Use a wire gauge tool to check
the gap on the spark plug.
/
Note: In some areas, local law requires using a resistor
spark plug to suppress ignition signals. If this engine
was originally equipped with a resistor spark plug, use
same type for replacement.
Do not use water to clean engine parts. Water
could contaminate fuel system. Use a brush or dry
c oth.
WARNING
Engine parts should be kept clean to reduce the risk
of overheating and ignition of accumulated debris.
,WARNING
Ensure air cleaner, retainer, and cover are
properly installed before starting engine.
Fuel System
WARNING
Replacement parts for fuel system (cap, hoses,
tanks, filters, etc.) must be the original parts, other-
wise fire can occur.
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