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For 1990-2009 cars only

Cooling System Draining and Filling LP1, LY7 Static Fill

Tools Required

J 38185 Hose Clamp Pliers

Draining Procedure

  1. Park the vehicle on a level surface.
  2. Remove the surge tank cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  4. Remove the air deflector. Refer to Front Air Deflector Replacement in Body Front End.
  5. Place a drain pan under the lower radiator hose connection at the bottom of the radiator.
  6. Using J 38185 slide the hose clamp back on the hose.
  7. Slowly remove the lower radiator hose and drain the coolant into the drain pan.
  8. Inspect the engine coolant for the following conditions:
  9. • Discolored appearance -- follow the flush procedure. Refer to Flushing .
    • Normal in appearance -- follow the filling procedure.

Filling Procedure

  1. Install the lower radiator hose.
  2. Using J 38185 slide the clamp into the original position.
  3. Lower the vehicle.
  4. Using J 38185 remove the upper radiator hose from the radiator connection.
  5. Slowly add a mixture of 50/50 DEX-COOL antifreeze and deionized water to the cooling system through the top of the radiator opening. Refer to Approximate Fluid Capacities in General Information.
  6. Fill the upper radiator hose and engine with the 50/50 coolant mixture.
  7. Connect the upper radiator hose to the engine.
  8. Using J 38185 slide the radiator hose clamp into the original position.
  9. Fill the surge tank to the FULL COLD level.
  10. Install the surge tank cap.
  11. Idle the engine for 2 minutes and occasionally raise the throttle to 3,000-3,500 RPM.
  12. Shut off the engine and allow the engine to cool.
  13. Repeat the steps 1-9.
  14. Idle the engine for 2 minutes and occasionally raise the throttle to 3,000-3,500 RPM.
  15. Inspect the surge tank for consistent flow.
  16. If no flow occurs through the surge tank, repeat steps 1-9.
  17. Install the air deflector. Refer to Front Air Deflector Replacement in Body Front End.
  18. Allow the engine to cool.
  19. Remove the surge tank cap and fill to the FULL COLD level.

Cooling System Draining and Filling LS2 Static Fill

Tools Required

J 38185 Hose Clamp Pliers

Draining Procedure

  1. Park the vehicle on a level surface.
  2. Remove the surge tank cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Remove the air deflector. Refer to Front Air Deflector Replacement .
  5. Place a drain pan under the lower radiator hose connection at the bottom of the radiator.
  6. Using J 38185 slide the hose clamp back on the hose.
  7. Slowly remove the lower radiator hose and drain the coolant into the drain pan.
  8. Inspect the engine coolant for the following conditions:
  9. • Discolored appearance--Follow the flush procedure. Refer to Flushing .
    • Normal in appearance--Follow the filling procedure.

Filling Procedure

  1. Install the lower radiator hose.
  2. Using J 38185 slide the clamp into the original position.
  3. Lower the vehicle.
  4. Slowly add a mixture of 50/50 DEX-COOL antifreeze and deionized water to the cooling system. Refer to Approximate Fluid Capacities .
  5. Fill the surge tank to the FULL COLD level.
  6. Install the surge tank cap.
  7. Idle the engine for 2 minutes and occasionally raise the throttle to 3,000-3,500 RPM.
  8. Shut off the engine and allow the engine to cool.
  9. Repeat the steps 1-9.
  10. Idle the engine for 2 minutes and occasionally raise the throttle to 3,000-3,500 RPM.
  11. Inspect the surge tank for consistent flow.
  12. If no flow occurs through the surge tank, repeat steps 1-9.
  13. Install the air deflector. Refer to Front Air Deflector Replacement .
  14. Allow the engine to cool.
  15. Remove the surge tank cap and fill to the FULL COLD level.

Cooling System Draining and Filling GE 47716

Tools Required

    • GE-47716 Vac N Fill Coolant Refill Tool
    • J 26568 Coolant and Battery Fluid Tester
    • 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 surge tank cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  4. Remove the air deflector. Refer to Front Air Deflector Replacement .
  5. Place a drain pan under the lower radiator hose connection at the bottom of the radiator.
  6. Using J 38185 , slide the hose clamp back on the hose.
  7. Slowly remove the lower radiator hose and drain the coolant into the drain pan.
  8. Inspect the engine coolant for the following conditions:
  9. • Discolored appearance--Follow the flush procedure. Refer to Flushing .
    • Normal in appearance--Follow the filling procedure.

Vac-N-Fill Procedure

  1. Install the J 42401 onto the coolant surge tank.
  2. 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.


    Object Number: 1617435  Size: SH
  3. Attach the Vac N Fill cap to the J 42401 .

  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 venturi assembly to the vacuum tank.

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


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

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

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

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

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

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

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

  38. Detach the vacuum hose from the vacuum gage assembly.

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

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

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