Cooling System: Service and Repair

Draining and Filling Cooling System

Draining Procedure





Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the pressure cap while the engine is hot and pressure is high will cause the solution to boil instantaneously possibly with explosive force-spewing the solution over the engine, fenders and the person removing the cap.

Caution: An electric fan under the hood can start up even when the engine is not running and can injure you. Keep hands, clothing and tools away from any underhood electric fan.

1. Remove the surge tank pressure cap.
1.1. Clean the cap.
1.2. Test the cap.
1.3. If necessary, replace the cap.
1.4. Clean the surge tank filler neck. Inspect the filler neck.
2. Remove the front air deflector.
3. Open the radiator drain at the bottom of the radiator.
4. Completely drain the cooling system.
5. If the coolant is dirty, or if there are deposits in the radiator, flush the cooling system before refilling.
6. Remove the surge tank.
6.1. Clean the outside of the surge tank.
6.2. Pour out any fluid.
6.3. Thoroughly clean the inside of the surge tank using soap and water.
6.4. Thoroughly flush the surge tank with clean water and drain.
7. Install the surge tank.
8. Close the radiator drain.
9. Install the front air deflector.

Filling Procedure





Notice: Do not add cold water to the cooling system with the engine at or above operating temperature. Adding cold water causes rapid cooling, resulting in possible engine damage.

Notice: When adding coolant, it is important that you use GM Goodwrench DEX-COOL or HAVOLINE DEX-COOL coolant. If Coolant other than DEX-COOL or HAVOLINE DEX-COOL is added to the system the engine coolant will require change sooner; at 50,000 km (30,000 mi) or 24 months.

Notice: Do not use a solution stronger than 70 percent antifreeze. Pure antifreeze can freeze at -22°C (-8°F).

Important: This engine is not equipped with block drains, 2.5 L (2 qt) of residual coolant remains in the engine block.

1. Refill the cooling system. In order to ensure sufficient engine cooling, freezing and corrosion protection, maintain the protection level at -37°C (-34°F) or lower.
2. Start the engine.
3. Place the heater and A/C control in any A/C mode except Max and the temperature in the highest setting.
4. Allow the engine to continue idling until the lower radiator to water pump hose is hot.
5. Turn OFF the engine.
6. Allow the engine to cool to outside temperature. Ensure the coolant level in the surge tank is at the proper level (1).

Flushing

Important: The thermostat should be removed before flushing the system.

Various methods and equipment may be used to flush the system. If using special equipment such as a back flusher, follow the manufacturer's instructions.

Radiator Cleaning

Caution: NEVER spray water on a hot radiator. The resulting steam could cause personal injury.

Notice: The radiator fins are necessary for good heat transfer. Do not brush the fins. This may cause damage to the fins, reducing heat transfer.

Important: Remove bugs, leaves, dirt and other debris by blowing compressed air through the engine side of the radiator.

^ Some conditions may require the use of warm water and a mild detergent.
^ Clean the A/C condenser fins.
^ Clean between the A/C condenser and radiator.
^ Clean the radiator cooling fins.
^ Straighten any damaged cooling fins.