ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines – Air Compressor Noise is Excessive

Carbon buildup is excessive in the air discharge line, check valve, or cylinder head

Check for carbon buildup. Replace the air compressor discharge line, if necessary. Refer to Procedure 010-033.

Ice buildup in the air system components

For all models, check for ice in low spots of the air discharge line, dryer inlet, and elbow fittings. On Holset® models, also check the Econ valve (if equipped). Refer to the OEM instructions.

Air compressor mounting hardware is loose, worn, or broken

Check air compressor mounting hardware. Refer to Procedure 012-014.

Air compressor is sending air pulses into the air tanks

Install a ping tank between the air dryer and the wet tank. Refer to the OEM instructions.

Air compressor drive gear or engine gear train is worn or damaged

Inspect the drive gears and gear train and repair as necessary. Refer to Procedure 012-014.

Splined drive coupling or gear is excessively worn

Check the coupling for wear. Refer to Procedure 012-014.

Air compressor is excessively worn or internally damaged

Replace or rebuild the air compressor. Refer to Procedure 012-014. Replace the desiccant element on the Turbo/CR 2000 air dryer (if equipped). Refer to the manufacturer’s instructions.