WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

NOTE: The illustrations shown will be of the SS model single cylinder air compressor. Differences in procedures for SS, QE and ST model Holset® air compressors will be illustrated where necessary.

Shut off the engine.

Open the drain cock on the wet tank to release compressed air from the system.

WARNING  Air discharge lines can be very hot. Be sure the lines are cool before touching to prevent personal injury.

Remove the air inlet and outlet connections from the air compressor.

Measure the total carbon deposit thickness inside the air discharge line as shown.

NOTE: The carbon deposit thickness must not exceed 1.6 mm [0.06 in].

WARNING  The air discharge line must be capable of withstanding extreme heat and pressure to prevent personal injury and property damage. Refer to the OEM service manual.

NOTE: If the total carbon deposit thickness exceeds specification, remove and clean, or replace the air discharge line. Refer to the OEM service manual.

WARNING  The air discharge line must be capable of withstanding extreme heat and pressure to prevent personal injury and property damage. Refer to the OEM service manual.

Continue to check for carbon buildup in the air discharge line connections up to the first connection, or wet tank.

Clean or replace any lines and fittings with carbon deposits greater than 1.6 mm [0.06 in]. Refer to the OEM service manual.

CAUTION  Do not use a sharp object to remove carbon. The sealing surfaces can be damaged.

Remove the air compressor head and valve assembly. Refer to the Holset® Air Compressor Master Repair Manual, Bulletin 3666121.

NOTE: Notall air compressors referenced may be used on your engine or application.

CAUTION  Do not use caustic cleaners on aluminum parts.

Clean the compressor head and valve assembly components with solvent and a nonmetallic brush to remove carbon.

Inspect the valve assembly components for reuse. Refer to the Holset® Air Compressor Master Repair Manual, Bulletin 3666121.

NOTE: Notall air compressors referenced may be used on your engine or application.

Assemble the air compressor using new gaskets and o-rings. Refer to the Holset® Air Compressor Master Repair Manual, Bulletin 3666121.

NOTE: Notall air compressors referenced may be used on your engine or application.

Install and tighten the air inlet and outlet connections.

Close the wet tank drain cock.

Operate the engine and check for air leaks.