GM Service Manual Online
For 1990-2009 cars only

Cooling System Draining and Filling LZ4, LZ9

Tools Required

J 26568 Coolant and Battery Fluid Tester

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.


    Object Number: 1824848  Size: SH
  1. Unscrew the surge tank cap to remove vacuum when draining coolant.
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  3. Place a container under the radiator drain.

  4. Object Number: 1212661  Size: SH
  5. Unscrew the radiator drain plug until coolant flows out the radiator drain.
  6. If a complete block drain is required, remove the coolant drain plugs. Refer to Draining Fluids and Oil Filter Removal for the 3.5L engine or Draining Fluids and Oil Filter Removal for the 3.9L engine.
  7. Follow the appropriate procedure based on the condition of the coolant:
  8. • Normal in appearance--Follow the filling procedure.
    • Discolored--Follow the flush procedure. Refer to Flushing .

Fill 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 engine block coolant drain plugs. Refer to Engine Block Assemble for the 3.5L engine or Engine Block Assemble for the 3.9L engine.
  2. Close the radiator drain plug.
  3. Lower the vehicle.
  4. Vehicle should be level.

  5. Object Number: 1824849  Size: SH

    Important: Do not overfill and allow the coolant to cover the surge tank inlet hose port.

  6. Add a mixture of 50/50 DEX-COOL® antifreeze and clean drinkable water until the level stabilizes approximately 1 in (25.4 mm) above the weld seam on the surge tank Refer to Approximate Fluid Capacities .

  7. Object Number: 1824848  Size: SH
  8. Install the surge tank cap.
  9. Important: DO NOT exceed 2,200 RPM.

  10. Start the engine and run at 2,000 RPM until the engine cooling fans turn ON.
  11. Let the engine idle for 30 seconds.
  12. Turn the engine OFF and allow the engine to cool down.
  13. Remove the surge tank cap.
  14. Refill to approximately 1 in (25.4 mm) above the weld seam on the surge tank.
  15. Inspect the concentration of the engine coolant using J 26568 .
  16. Install the surge tank cap.
  17. Rinse away any excess coolant from the engine and the engine compartment.

Cooling System Draining and Filling GE 47716

Tools Required

    • J 26568 Coolant and Battery Fluid Tester
    • J 42401 Radiator Pressure Adapter
    • GE-47716 Vac N Fill Coolant Refill Tool

Draining Procedure


    Object Number: 1824848  Size: SH
  1. Unscrew the surge tank cap to remove vacuum when draining the coolant.
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  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 drain plugs. Refer to the following:
  6. •  Draining Fluids and Oil Filter Removal for the 2.2L engine
    •  Draining Fluids and Oil Filter Removal for the 3.5L engine
    •  Draining Fluids and Oil Filter Removal for the 3.9L engine
  7. Follow the appropriate procedure based on the condition of the coolant.
  8. • 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.

If a complete engine block drain was required, install the engine block drain plugs. Refer to the appropriate procedure:

    •  Engine Block Assemble for the 2.2L engine
    •  Engine Block Assemble for the 3.5L engine
    •  Engine Block Assemble for the 3.9L engine

    Object Number: 1617435  Size: SH
  1. Install J-42401-2 into the surge tank fill neck.
  2. Install J-42401-3 to the surge tank fill neck.
  3. Attach the Vac N Fill cap to the J-42401-3.
  4. Attach the Vac N Fill cap to the vehicles coolant fill port.

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

  7. Object Number: 1617437  Size: SH
  8. Attach the fill hose to the barb fitting on the vacuum gage assembly.
  9. Ensure 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.

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

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

  14. Object Number: 1617439  Size: SH
  15. Attach the venturi assembly to the vacuum tank.

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


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

  20. Object Number: 1617442  Size: SH
  21. Open the valve on the venturi 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.
  28. This will eliminate air from the fill hose.

  29. Close the valve on the venturi assembly.
  30. If there is a suspected leak in the cooling system, allow the system to stabilize under vacuum and monitor for vacuum loss.
  31. If vacuum loss is observed, refer to Loss of Coolant .

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

  33. Object Number: 1617448  Size: SH
  34. Once the vacuum gage reaches zero, close the valve on the vacuum gage assembly and repeat steps 11-17.
  35. Remove the J-42401-3 from the surge tank fill neck.
  36. Remove J-42401-2 from the surge tank fill neck.
  37. Detach the Vac N Fill cap from the vehicles coolant fill port.
  38. Add coolant to the system as necessary.
  39. Inspect the concentration of the coolant mixture using J 26568 .
  40. Important: After filling the cooling system, the extraction hose can be used to remove excess coolant to achieve the proper coolant level.

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

  42. Object Number: 1617450  Size: SH
  43. Attach the extraction hose to the vacuum hose.

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

  46. Object Number: 1617456  Size: SH
  47. Use the extraction hose to draw out coolant to the proper level.
  48. Install the surge tank cap.
  49. 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.

Cooling System Draining and Filling L61

Special Tools

J 26568 Coolant and Battery Fluid Tester

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.


    Object Number: 1824848  Size: SH
  1. Unscrew the surge tank cap to remove vacuum when draining coolant.
  2. Place a container under the radiator drain.

  3. Object Number: 1212661  Size: SH
  4. Unscrew the radiator drain plug until coolant flows out of the radiator drain.
  5. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .

  6. Object Number: 1212666  Size: SH

    Important: Draining at water pump will drain the heater core and some of the engine block.

  7. Place a container under the water pump housing and open the water pump drain plug.
  8. Follow the appropriate procedure based on the condition of coolant.
  9. • Normal in appearance--Follow filling procedure.
    • Discolored--Follow flush procedure. Refer to Flushing .

Fill 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. Close the radiator drain plug.
  2. Close the water pump drain plug. Refer to Water Pump Installation for the 2.2L.(L61) engine.
  3. Lower the vehicle.
  4. Vehicle should be level.

  5. Object Number: 1824849  Size: SH
  6. Add a mixture of  50/50 DEX-COOL® antifreeze and clean drinkable water until the level stabilizes approximately 25.4 mm (1.0 in) above the weld seam on the surge tank. Refer to Approximate Fluid Capacities .

  7. Object Number: 1824848  Size: SH
  8. Install the surge tank cap.
  9. Important: DO NOT exceed 2,200 RPM.

  10. Start the engine and run at 2,000 RPM until the engine cooling fans turn ON.
  11. Turn the engine OFF and allow the engine to cool down.
  12. Remove the surge tank cap.
  13. Refill to approximately 25.4 mm (1.0 in) above the weld seam on the surge tank.
  14. Inspect the concentration of engine coolant using J 26568 .
  15. Install the surge tank cap.
  16. Rinse away any excess coolant from the engine and the engine compartment.