Honda EM4000SX Owner's Manual page 54

SERVICING YOUR GENERATOR
5. Reinstall the air cleaner element in the air cleaner case.
6. Set the hooks of the air cleaner cover to the setting pins securely,
and then push the air cleaner cover to lock the clips.
Be sure that the cover is set securely. There must be no clearance
between the air cleaner cover and air cleaner case.
Operating the engine without an air filter or with a damaged air filter
will allow dirt to enter the engine, causing rapid engine wear. This
type of damage is not covered by the Distributor's Limited Warranty.
SETTING PIN
AIR CLEANER COVER
52
GOOD
HOOK
AIR CLEANER CASE
AIR CLEANER ELEMENT
NO GOOD
CLIP