1985/06/01 Caterpillar

3406, 3406B Truck Engines

Truck manufacturers have the responsibility for correct plumbing of the air compressor. An incorrect installation can cause an early failure in cold weather. Water freezing in the discharge line can cause a buildup of compressor head pressure, resulting in damage to bearings, crankshafts and head gaskets. To prevent early failures during cold weather, the discharge line should slope downward from the compressor to the tank, air dryer or other water removal device.

The air governor line should also slope downward. A frozen governor line can cause the compressor to stay in the loaded position. Incorrect installations that reflect on Caterpillar Engines should be pointed out to the user.