Cooling System Draining and Filling (Vac-N-Fill)
Cooling System Draining and Filling (LS4 GE 47716 Fill) (5.3L)
Special Tools
* J 26568 - Coolant and Battery Fluid Tester
* J 42401 - Radiator Cap and Surge Tank Test Adapter
* GE-47716 - Vac N Fill Coolant Refill Tool
Draining Procedure
Warning: Refer to Radiator Cap Removal Warning (Service Precautions).
Note: Draining the cooling system with the pressure cap installed will syphon the coolant from the overflow tank.
1. Remove the coolant pressure cap.
2. Place a drain pan under the drain cock.
3. Open the radiator drain cock.
4. Drain the cooling system.
5. If a complete engine block drain is required, remove the engine block drain plugs. Refer to Draining Fluids and Oil Filter Removal (Overhaul).
6. Inspect the coolant.
7. 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 (Service and Repair).
Vac-N-Fill Procedure
1. If a complete engine block drain was required, install the engine block drain plugs. Refer to Draining Fluids and Oil Filter Removal (Overhaul).
Note: To prevent boiling of the coolant/water mixture in the vehicle's cooling system, do not apply vacuum to a cooling system above 49° C (120° F). The tool will not operate properly when the coolant is boiling.
2. Install the J 42401 - Radiator Cap and Surge Tank Test Adapter to the coolant fill port.
3. Attach the Vac N Fill cap to the J 42401 - Radiator Cap and Surge Tank Test Adapter.
4. Attach the fill hose to the barb fitting on the vacuum gage assembly.
Ensure that the valve is closed.
5. Attach the vacuum gage assembly to the Vac N Fill cap.
Note: Use a 50/50 mixture of DEX-COOL(R) antifreeze and clean, drinkable water.
Always use more coolant than necessary. This will eliminate air from being drawn into the cooling system.
6. Pour the coolant mixture into the graduated reservoir.
7. Place the fill hose in the graduated reservoir.
Note: Prior to installing the vacuum tank onto the graduated reservoir, ensure that the drain valve located on the bottom of the tank is closed.
8. Install the vacuum tank on the graduated reservoir with the fill hose routed through the cut-out area in the vacuum tank.
9. Attach the venturi assembly to the vacuum tank.
10. Attach a shop air hose to the venturi assembly.
Ensure the valve on the venturi assembly is closed.
11. Attach the vacuum hose to the vacuum gage assembly and the vacuum tank.
12. Open the valve on the venturi assembly. The vacuum gage will begin to rise and a hissing noise will be present.
13. Continue to draw vacuum until the needle stops rising. This should be 610-660 mm Hg (24-26 in Hg).
Cooling hoses may start to collapse. This is normal due to vacuum draw.
14. To aid in the fill process, position the graduated reservoir above the coolant fill port.
15. Slowly open the valve on the vacuum gage assembly. When the coolant reaches the top of the fill hose, close the valve. This will eliminate air from the fill hose.
16. Close the valve on the venturi assembly.
17. If there is a suspected leak in the cooling system, allow the system to stabilize under vacuum and monitor for vacuum loss.
If vacuum loss is observed. Refer to Loss of Coolant (Loss of Coolant).
18. Open the valve on the vacuum gage assembly. The vacuum gage will drop as coolant is drawn into the system.
Note: Complete 2 vacuum pulls to sufficiently fill the cooling system.
19. Once the vacuum gage reaches zero, close the valve on the vacuum gage assembly and repeat steps 11-17.
20. Detach the Vac N Fill cap from the J 42401 - Radiator Cap and Surge Tank Test Adapter.
21. Remove the J 42401 - Radiator Cap and Surge Tank Test Adapter from the coolant fill port.
22. Add coolant to the system as necessary.
23. Inspect the concentration of the coolant mixture using the J 26568 - Coolant and Battery Fluid Tester.
Note: After filling the cooling system, the extraction hose can be used to remove excess coolant to achieve the proper coolant level.
24. Detach the vacuum hose from the vacuum gage assembly.
25. Attach the extraction hose to the vacuum hose.
26. Open the valve on the venturi assembly to start a vacuum draw.
27. Use the extraction hose to draw out coolant to the proper level.
28. The vacuum tank has a drain valve on the bottom of the tank. Open the valve to drain coolant from the vacuum tank into a suitable container for disposal.
29. Fill the coolant recovery bottle to the indicator line, then add 400 milliliters (13.5 ounces) more.
30. Install the coolant pressure cap.
31. Start the engine and run it above 2500 RPM until it is hot enough to open the thermostat.
32. Complete a series of 3, 4-second-duration idles with 4-second-duration 3,000 RPM cycles.
33. Turn the engine OFF and allow it to cool down to room temperature.
34. Ensure the coolant recovery bottle is filled to the indicator line or above.