GM Service Manual Online
For 1990-2009 cars only

Cooling System Draining and Filling w/RPO HP2

Tools Required

    •  J 26568 Coolant and Battery Tester
    •  J 38185 Hose Clamp Pliers

Draining Procedure

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.

  1. Follow the steps below in order to remove the surge tank fill cap.
  2. 1.1. Slowly rotate the cap counterclockwise.
    1.2. Stop rotating and allow the hissing to stop.
    1.3. After all the hissing stops, continue turning counterclockwise in order to remove the cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Place a drain pan under the lower radiator hose.
  5. Using the J 38185 , reposition the lower radiator hose clamp.
  6. Remove the lower radiator hose from the radiator.
  7. Drain the cooling system.

  8. Object Number: 635657  Size: SH
  9. If a complete engine block drain is required, remove the left and right engine block coolant drain plugs.
  10. Remove the engine block coolant heater, if equipped. Refer to Coolant Heater Replacement .
  11. Inspect the coolant.
  12. Follow the appropriate procedure based on the condition of the coolant.
  13. • Normal in appearance--Follow the filling procedure.
    • Discolored--Follow the flush procedure. Refer to Flushing .

Filling Procedure

    Notice: 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 lower radiator hose to the radiator.
  2. Using the J 38185 reposition the lower radiator hose clamp.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. If the left and right engine block coolant drain plugs were removed, perform the following.
  5. 3.1. Apply pipe sealer to the drain plugs.
    3.2. Install the drain plugs.

    Tighten
    Tighten the drain plugs to 60 N·m (44 lb ft).

  6. Install the engine block coolant heater, if equipped. Refer to Coolant Heater Replacement .
  7. Lower the vehicle.
  8. Open the cooling system bleeder screws, if applicable.
  9. Important: Use a 50/50 mixture of DEX-COOL antifreeze and clean, drinkable water.

  10. Slowly fill the cooling system with a 50/50 coolant mixture. Refer to Approximate Fluid Capacities .
  11. Close the cooling system bleeder screws, if applicable.
  12. Install the coolant pressure cap.
  13. Start the engine.
  14. Run the engine at 2,000-2,500 RPM until the engine reaches normal operating temperature.
  15. Allow the engine to idle for 3 minutes.
  16. Perform the following step 4 times:
  17. 13.1. Run the engine at 4,000 RPM for 30 seconds.
    13.2. Allow the engine to return to idle for 30 seconds.
  18. Shut the engine OFF.
  19. Allow the engine to cool.
  20. Top off the coolant as necessary.
  21. Inspect the concentration of the engine coolant using the J 26568 .
  22. Rinse away any excess coolant from the engine and the engine compartment.

Cooling System Draining and Filling Static Fill

Tools Required

    •  J 26568 Coolant and Battery Tester
    •  J 38185 Hose Clamp Pliers

Draining Procedure

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.

  1. Follow the steps below in order to remove the surge tank fill cap.
  2. 1.1. Slowly rotate the cap counterclockwise.
    1.2. Stop rotating and allow the hissing to stop.
    1.3. After all the hissing stops, continue turning counterclockwise in order to remove the cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Place a drain pan under the lower radiator hose.
  5. Using the J 38185 , reposition the lower radiator hose clamp.
  6. Remove the lower radiator hose from the radiator.
  7. Drain the cooling system.

  8. Object Number: 635657  Size: SH
  9. If a complete engine block drain is required, remove the left and right engine block coolant drain plugs.
  10. Remove the engine block coolant heater, if equipped. Refer to Coolant Heater Replacement .
  11. Inspect the coolant.
  12. Follow the appropriate procedure based on the condition of the coolant.
  13. • Normal in appearance--Follow the filling procedure.
    • Discolored--Follow the flush procedure. Refer to Flushing .

Filling Procedure

    Notice: 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 lower radiator hose to the radiator.
  2. Using the J 38185 reposition the lower radiator hose clamp.
  3. If the left and right engine block coolant drain plugs were removed, perform the following.
  4. 3.1. Apply pipe sealer to the drain plugs.

    Notice: Refer to Fastener Notice in the Preface section.

    3.2. Install the drain plugs.

    Tighten
    Tighten the drain plugs to 60 N·m (44 lb ft).

  5. Install the engine block coolant heater, if equipped. Refer to Coolant Heater Replacement .
  6. Lower the vehicle.
  7. Open the cooling system bleeder screws, if equipped.
  8. Important: Use a 50/50 mixture of DEX-COOL antifreeze and clean, drinkable water.

  9. Slowly fill the cooling system with a 50/50 coolant mixture. Refer to Approximate Fluid Capacities .
  10. Close the cooling system bleeder screws, if equipped.
  11. Install the coolant pressure cap.
  12. Start the engine.
  13. Run the engine at 2,000-2,500 RPM until the engine reaches normal operating temperature.
  14. Allow the engine to idle for 3 minutes.
  15. Shut the engine OFF.
  16. Allow the engine to cool.
  17. Top off the coolant as necessary.
  18. Inspect the concentration of the engine coolant using the J 26568 .
  19. Rinse away any excess coolant from the engine and the engine compartment.

Cooling System Draining and Filling Vac-N-Fill

Tools Required

    • J 26568 Coolant and Battery Tester
    • GE-47716 Vac-N-Fill Coolant Refill Tool
    • J 42401 Radiator Cap and Surge Tank Test Adapter

Draining Procedure

Caution: 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. Park the vehicle on a level surface.
  2. Remove the coolant pressure cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  4. Place a drain pan under the drain cock and/or lower radiator hose.
  5. Reposition the radiator drain cock and/or lower radiator hose.
  6. Drain the cooling system.
  7. If a complete engine block drain is required, remove the engine block drain plug.
  8. Inspect the coolant.
  9. Follow the appropriate procedure based on the condition of the coolant.
  10. • Normal in appearance--Follow the filling procedure.
    • Discolored--Follow the flush procedure. Refer to Flushing.

Vac-N-Fill Procedure

Important: To prevent boiling of the coolant/water mixture in the vehicles 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.

  1. Install the J 42401 .

  2. Object Number: 1617435  Size: SH
  3. Attach the Van-N-Fill cap to the vehicles coolant fill port.

  4. Object Number: 1617436  Size: SH
  5. Attach the vacuum gage assembly to the Vac-N-Fill cap.

  6. Object Number: 1617437  Size: SH
  7. Attach the fill hose to the barb fitting on the vacuum gage assembly.
  8. Ensure that the valve is closed.


    Object Number: 1617438  Size: SH

    Important: Use a 50/50 mixture of DEX-COOL antifreeze and clean, drinkable water. Always use more coolant than necessary. This will eliminate air from being drawn into the cooling system.

  9. Pour the coolant mixture into the graduated reservoir.
  10. Place the fill hose in the graduated reservoir.
  11. Important: Prior to installing the vacuum tank onto the graduated reservoir, ensure that the drain valve located on the bottom of the tank is closed.

  12. Install the vacuum tank on the graduated reservoir with the fill hose routed through the cut-out area in the vacuum tank.

  13. Object Number: 1617439  Size: SH
  14. Attach the venture assembly to the vacuum tank.

  15. Object Number: 1617440  Size: SH
  16. Attach a shop air hose to the venture assembly.
  17. Ensure the valve on the venture assembly is closed.


    Object Number: 1617441  Size: SH
  18. Attach the vacuum hose to the vacuum gage assembly and the vacuum tank.
  19. Clamp off the overflow hose.

  20. Object Number: 1617442  Size: SH
  21. Open the valve on the venture assembly. The vacuum gage will begin to rise and a hissing noise will be present.

  22. Object Number: 1617443  Size: SH
  23. Continue to draw vacuum until the needle stops rising. This should be 610-660 mm Hg (24-26 in Hg).
  24. Cooling hoses may start to collapse. This is normal due to vacuum draw.

  25. To aid in the fill process, position the graduated reservoir above the coolant fill port.

  26. Object Number: 1617446  Size: SH
  27. 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.
  28. Close the valve on the venture assembly.
  29. If there is a suspected leak in the cooling system, allow the system to stabilize under vacuum and monitor for vacuum loss.
  30. If vacuum loss is observed, refer to Loss of Coolant.

  31. Open the valve on the vacuum gage assembly. The vacuum gage will drop as coolant is drawn into the system.

  32. Object Number: 1617448  Size: SH
  33. Once the vacuum gage reaches zero, close the valve on the vacuum gage assembly and repeat steps 11-17.
  34. Remove the J 42401 .
  35. Detach the Vac-N-Fill cap from the vehicles coolant fill port.
  36. Add coolant to the system as necessary.
  37. Inspect the concentration of the coolant mixture using J 26568 .
  38. Important: After filling the cooling system, the extraction hose can be used to remove excess coolant to achieve the proper coolant level.

  39. Detach the vacuum hose form the vacuum gage assembly.

  40. Object Number: 1617450  Size: SH
  41. Attach the extraction hose to the vacuum hose.

  42. Object Number: 1617453  Size: SH
  43. Open the valve on the venture assembly to start a vacuum draw.

  44. Object Number: 1617456  Size: SH
  45. Use the extraction hose to draw out coolant to the proper level.
  46. 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.