Honda HP500H Manuel De L'utilisateur page 19

Air cleaner
Check that the foam element is clean and in good condition. A dirty air
cleaner will restrict air flow to the carburetor, reducing engine
performance. A damaged air cleaner will allow dirt to enter the engine,
causing rapid engine wear.
1.Unscrew the wing nut, remove the air cleaner cover.
2.Remove and inspect the foam element.
If the element is dirty, follow the cleaning procedure described on
page 39.
3.Reinstall the foam element, cover and wing nut. Securely tighten the
wing nut.
CAUTION:
Never run the engine without the air cleaner. Rapid engine wear will
result from contaminants, such as dust and dirt, being drawn through
the carburetor, into the engine.
WING NUT
AIR CLEANER COVER
FOAM ELEMENT
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