1. Remove the vacuum check valve (1) and grommet.
2. Remove the boot and air filter.
3. Inspect the boot, front housing seal, and grommet for cuts, nicks and excessive wear.

Replace part(s) if any of the above conditions are found.

4. Clean the above parts in clean denatured alcohol.
5. Dry with unlubricated compressed air.

Important: Lubricate the inside and outside diameters of the grommet and the front housing seal with a thin layer of silicone grease.

1. Install the air filter and the boot.
2. Install the grommet and the vacuum check valve (1).