Draining Procedure: Notes

CAUTION: 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.

Follow the steps below in order to remove the surge tank fill cap.
1. Slowly rotate the cap counterclockwise.
2. Stop rotating and allow the hissing to stop.
3. After all the hissing stops, continue turning counterclockwise in order to remove the cap.
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
Place a drain pan under the lower radiator hose.
Using the J 38185 , reposition the lower radiator hose clamp. See Special Tools .
Remove the lower radiator hose from the radiator.
Drain the cooling system.

Fig 1: View Of Engine Coolant Drain Hole Plug

Courtesy of GENERAL MOTORS CORP.

If a complete engine block drain is required, remove the left and right engine block coolant drain plugs.
Remove the engine block coolant heater, if equipped. Refer to Coolant Heater Replacement .
Inspect the coolant.
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 .