Cooling System Draining and Filling (Static Fill)

Cooling System Draining and Filling (LS3, L99 Static Fill)

Special Tools

J 26568 - Coolant and Battery Fluid Tester

Draining Procedure

Warning

To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.

1. Remove the coolant pressure cap from the radiator.
2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle (Service and Repair).
3. Place a clean drain pan under the radiator drain cock.
4. Loosen the radiator drain cock.
5. Drain the cooling system.
6. Lower the vehicle.
7. Inspect the coolant.
8. Follow the appropriate procedure based on the condition of the coolant.

* Normal in appearance-Follow the filling procedure.
* Discolored-Follow the flush procedure. Refer to Flushing (Flushing).

9. Tighten the radiator drain cock.
10. Lower the vehicle.

Filling Procedure

Caution: The procedure below must be followed. Improper coolant level could result in a low or high coolant level condition, causing engine damage.

Note: Use a 50/50 mixture of DEX-COOL antifreeze and clean drinkable water.

1. Slowly fill the radiator with a 50/50 coolant mixture until the coolant level is just below the radiator fill neck. Refer to Approximate Fluid Capacities ([1][2]Maintenance).
2. Allow 30 seconds for the coolant level to stabilize and continue to fill the radiator until the level stabilizes for at least 2 minutes.
3. Start the engine and allow to the engine to idle.
4. Slowly fill the coolant mixture until the level stabilizes at the just below the top of radiator fill neck for at least 2 minutes.
5. Install the coolant pressure cap.
6. Allow the engine to idle until the engine reaches normal operating temperature.
7. Shut the engine OFF.
8. Allow the engine to cool.
9. Remove the coolant pressure cap and top off the engine coolant in the radiator.
10. Inspect the concentration of the engine coolant using the J 26568 - Coolant and Battery Fluid Tester.
11. Install coolant pressure cap.
12. Inspect and if necessary, fill the coolant reservoir bottle.
13. Rinse away any excess coolant from the engine and the engine compartment
14. Inspect the cooling system for leaks.
15. Top off the coolant reservoir if necessary.