Cooling System Draining and Filling

Cooling System Draining and Filling (LY7, LZE, LZ4, LZ9) (3.5L)

Special Tools

J 26568 Coolant and Battery Fluid Tester

Draining Procedure

Warning

With a pressurized cooling system, the coolant temperature in the radiator can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the cooling system is hot and under high pressure, causes the solution to boil instantaneously with explosive force. This will cause the solution to spew out over the engine, the fenders, and the person removing the cap. Serious bodily injury may result.




1. Unscrew the surge tank cap to remove vacuum when draining coolant.
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle Service and Repair.
3. Place a container under the radiator drain.




4. Unscrew the radiator drain plug until coolant flows out the radiator drain.
5. If a complete block drain is required, remove the coolant drain plugs. Refer to Draining Fluids and Oil Filter Removal 1. Draining Fluids and Oil Filter Removal for the 3.5L engine, Engine Block Disassemble 6. 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.

Fill Procedure

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



1. Install the engine block coolant drain plugs. Refer to the appropriate procedure:

* Engine Block Assemble 24. Engine Block Assemble for the 3.5L engine.

2. Close the radiator drain plug.
3. Lower the vehicle.
4. Vehicle should be level.




5. Add a mixture of 50/50 DEX-COOL(R) antifreeze and clean drinkable water until the level stabilizes approximately 1" (25.4 mm) above the weld seam on the surge tank. Refer to Approximate Fluid Capacities [1][2]Maintenance.




6. Install the surge tank cap.

Note: DO NOT exceed 2,200 RPM.

7. Start the engine and run at 2,000 RPM until the engine cooling fans turn ON.
8. Turn the engine OFF and allow the engine to cool down.
9. Remove the surge tank cap.
10. Refill to approximately 1" (25.4 mm) above the weld seam on the surge tank.
11. Install the surge tank cap.
12. Inspect the concentration of the engine coolant using J 26568 .
13. Install the surge tank cap.
14. Rinse away any excess coolant from the engine and the engine compartment.