Yamaha EF1400 Owner's Manual page 23

J-100
Air filter element cleaning
Remove the air filter cover and the filter element.
Wash the element in gasoline and dip it in engine
oil.
Lightly squeeze it to remove excess oil and install.
f-WARNING:- -i
Do not smoke or allow open flames or
sparks near any flammable solvent.
CAUTION:
Do not operate the engine with the air cleaner
removed,
CAUTION:
Do not squeeze the element as illustrated, or
the element could be broken.
DO NOT SQUEEZE
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