GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN 384 Valve Spring Compressor - Head Off
    • EN 46116 Valve Stem Seal Remover/Installer
    •  EN 46117 Valve Stem Key Remover/Installer
    • EN 46119 Off-Vehicle Valve Spring Compressor Adapter

For equivalent regional tool, refer to Special Tools.


    Object Number: 1930294  Size: SH
  1. Remove the engine coolant temperature (ECT) sensor.

  2. Object Number: 1950092  Size: SH
  3. Remove the spark plugs.

  4. Object Number: 1210820  Size: SH

    Note: Ensure valve heads will not contact anything during the following step in order to avoid bending or damage.

  5. Using an appropriately sized deep socket and a plastic hammer, lightly tap on the valve spring retainer to loosen the valve keepers.

  6. Object Number: 1210825  Size: SH

    Warning: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

    Caution: Do not compress the valve springs less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

  7. Compress the valve spring using the EN 384 compressor and the EN 46119 adapter .

  8. Object Number: 1210829  Size: SH
  9. Use the magnet of the EN 46117 remover in order to remove the valve keepers.
  10. Remove the valve spring compressor and the adapter.

  11. Object Number: 1210879  Size: SH
  12. Remove the valve spring retainer.
  13. Remove the valve spring.

  14. Object Number: 1210884  Size: SH
  15. Remove the valve.

  16. Object Number: 1210887  Size: SH

    Note: NEVER reuse a valve stem oil seal.

  17. Remove the valve stem oil seal using the EN 46116 remover/installer and discard.
  18. Repeat these procedures for the remaining valves.

  19. Object Number: 1210891  Size: SH
  20. Remove the cylinder head oil gallery expansion plugs.

  21. Object Number: 1210901  Size: SH
  22. Remove the cylinder head coolant threaded plugs.