Spark Arrester Cleaning - Yamaha YFM400FT Owner's Manual

CAUTION:
_
Never operate the engine with the air filter
element removed. This will allow unfiltered
air to enter, causing rapid engine wear and
possible engine damage. Additionally, op-
eration without the air filter element will af-
fect carburetor jetting with subsequent
poor performance and possible engine
overheating.
_
EBU00754

Spark arrester cleaning

Select a well-ventilated area free of combusti-
ble materials and make sure the exhaust pipe
and muffler are cool.
1. Remove the purging bolt.
1. Purging bolt
2. Start the engine and rev it up approxi-
mately twenty times while momentarily
creating exhaust system back pressure
by blocking the end of the muffler with a
shop towel.
3. Stop the engine and allow the exhaust
pipe to cool.
4. Install the purging bolt and tighten it.
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