Komatsu PC78US-6 Operation & Maintenance Manual page 201

MAINTENANCE
WHEN REQUIRED
CHECK, CLEAN AND REPLACE AIR CLEANER ELEMENT
If inspection, cleaning, or maintenance is carried out with the engine running, dirt will get into the engine and the engine will
suffer damage. Always stop the engine before carrying out these operations.
When using compressed air, there is danger that dirt may be blown around and cause serious injury.
Always use safety glasses, dust mask, and other protective equipment.
Checking
NOTICE
Do not clean the air cleaner element before the dust indicator becomes red.
If the element is cleaned frequently before the dust indicator becomes red,
the performamce of the aie cleaner is not used perfectly and the cleaning
effect is lowered. In addition, dust sticking to the element falls into the
inner element each time the element is cleaned.
Cleaning or replacing outer element
NOTICE
Never remove inner element (5). If it is removed, dust will enter and cause
an engine trouble.
MAINTENANCE PROCEDURE
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