Duramax LLY – FLUSHING ENGINE COOLER

Flush the engine oil cooler whenever a component failure contaminates the oil with metal or similar particles. The oil and filter should also be changed.

Cooler Flushing Procedure

1. Remove oil cooler lines at engine and allow oil to drain into suitable container.

2. With one line positioned in container, introduce air pressure (no more than 20 psi (140 kPa)) into the other line to force oil and contaminates out of cooler.

3. When cooler is clear of oil, use pump or vacuum unit to then either pump or draw solvent followed by fresh oil through cooler. Continue until oil coming from cooler is free of contaminants.

4. Reconnect cooler lines to engine adapter fittings.

5. Change engine oil and filter.