BLADE AS 4T9736 - Caterpillar

Always replace the secondary element. Do not attempt to reuse it by cleaning. Engine damage could result.
Note: Replace the secondary filter element when you service the primary element for the third time. If a clean primary element has been installed and the filter element indicator still enters the red zone, replace the secondary filter element. Also if the exhaust smoke remains black and a clean primary filter element has been installed, replace the secondary filter element.
Illustration 1 g00102925
Open the access cover (if equipped).
Remove the housing cover and the primary element.
Illustration 2 g00039214
Remove the secondary element.
Cover the air inlet opening. Clean the inside of the air cleaner housing.
Inspect the gasket between the air inlet and the housing. If the gasket is damaged, replace the gasket.
Uncover the air inlet opening. Install a new secondary element.
Install the primary element and the air cleaner housing cover.
Close the access cover (if equipped).