GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Corvette 🢒 Engine 🢒 Engine Cooling 🢒 Flushing

Flushing Powertrain

Note: Do not use a chemical flush.

Store used coolant in the proper manner, such as in a used engine coolant holding tank. Do not pour used coolant down a drain. Ethylene glycol antifreeze is a very toxic chemical. Do not dispose of coolant into the sewer system or ground water. This is illegal and ecologically unsound.

Various methods and equipment can be used to flush the cooling system. If special equipment is used, such as a back flusher, follow the manufacturer's instruction. Always remove the thermostat before flushing the cooling system.

When the cooling system becomes contaminated, the cooling system should be flushed thoroughly to remove the contaminants before the engine is seriously damaged.

  1. Drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Remove the surge tank. Refer to Radiator Surge Tank Replacement.
  3. Clean and flush the surge tank with clean, drinkable water.
  4. Install the surge tank. Refer to Radiator Surge Tank Replacement.
  5. Follow the drain and fill procedure using only clean, drinkable water. Refer to Cooling System Draining and Filling.
  6. Run the engine for 20 minutes.
  7. Stop the engine.
  8. Drain the cooling system. Refer to Cooling System Draining and Filling
  9. Repeat the procedure if necessary, until the fluid is nearly colorless.
  10. Fill the cooling system. Refer to Cooling System Draining and Filling.

Flushing Charged Air Cooling

Note: Do not use a chemical flush.

Store used coolant in the proper manner, such as in a used engine coolant holding tank. Do not pour used coolant down a drain. Ethylene glycol antifreeze is a very toxic chemical. Do not dispose of coolant into the sewer system or ground water. This is illegal and ecologically unsound.

Various methods and equipment can be used to flush the cooling system. If special equipment is used, such as a back flusher, follow the manufacturer's instruction. Always remove the thermostat before flushing the cooling system.

When the charge air cooling (CAC) cooling system becomes contaminated, the CAC cooling system should be flushed thoroughly to remove the contaminants before the supercharger is seriously damaged.

  1. Drain the CAC cooling system. Refer to Charge Air Cooling System Draining and Filling
  2. Follow the drain and fill procedure using only clean, drinkable water. Refer to Charge Air Cooling System Draining and Filling
  3. Command the CAC pump to the ON position using the Tech 2. Run the CAC pump for 5 minutes.
  4. Drain the CAC cooling system. Refer to Charge Air Cooling System Draining and Filling
  5. Repeat the procedure if necessary, until the fluid is nearly colorless.
  6. Fill the CAC cooling system. Refer to Charge Air Cooling System Draining and Filling