GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 22794 Spark Plug Port Adapter
    • J 38606 Valve Spring Compressor (Head-on)

Removal Procedure

    Important: Store all valve train components in the same order they are removed. Make sure all valve train components are installed in the same location as on removal.

  1. Remove the valve rocker arms. Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection .
  2. Remove the spark plug. Refer to Spark Plug Replacement .

  3. Object Number: 1954180  Size: SH

    Important: This operation can be performed with the cylinder at the bottom of its stroke, however with the piston at TDC the valve will not fall into the cylinder if the air supply is accidentally disconnected during the operation.

  4. Using a socket and handle on the crankshaft pulley retaining bolt, rotate the crankshaft until the piston of the cylinder being serviced is at the Top Dead Centre (TDC) of the compression stroke.

  5. Object Number: 1954191  Size: SH
  6. Install the J 22794  (1) or equivalent into the spark plug hole of the cylinder being serviced.
  7. Attach a compressed air line to J 22794  (1) and apply a constant supply of air pressure to the cylinder being serviced.
  8. Tap the end of the valve stem with a soft face hammer in order to dislodge the valve spring cap retaining collets.

  9. Object Number: 1954192  Size: SH
  10. Use J 38606  (1) in order to compress the valve spring (3).
  11. Remove the valve spring retaining cap collets (2).
  12. Carefully release the valve spring (3) tension.
  13. Remove the J 38606  (1).

  14. Object Number: 1954193  Size: SH
  15. Remove the valve spring cap (1).
  16. Remove the valve spring (2).
  17. Remove the valve stem oil seal (3).

Installation Procedure


    Object Number: 1954193  Size: SH
  1. Clean the cylinder head valve spring seat and/or shim area.
  2. Important: The valve stem oil seal alignment and position on the valve guide is critical. An incorrectly installed valve stem oil seal may lead to above acceptable oil consumption and increased vehicle emissions.

  3. Install the valve stem oil seal (3). onto the guide.
  4. Install the valve spring (2).
  5. Install the valve spring cap (1).

  6. Object Number: 1954192  Size: SH
  7. Use J 38606  (1) in order to compress the valve spring (3).
  8. Compress the valve spring using the J 38606  (1).
  9. Important: Use clean grease or petroleum jelly to retain the valve spring retaining collets (2)

  10. Install the valve spring retaining collets (2) .
  11. Release the J 38606  (1) making sure both valve spring retaining collets have seated correctly.
  12. Lightly tap the valve stem with a soft faced hammer to seat the valve stem collets.

  13. Object Number: 1954191  Size: SH
  14. Disconnect and remove the compressed air supply from the J 22794  (1).
  15. Remove the J 22794  (1) from the spark plug hole.

  16. Object Number: 1954194  Size: SH
  17. Measure the valve spring installed height using a ruler.
  18. Measure from the base of the valve spring to the top of the valve spring.

    • If the installed height exceeds 46.25 mm (1.82 in), install a valve spring shim of approximately 0.5 mm (0.02 in) thick.
    • Do not shim the valve spring to obtain less than the specified height.
    • Do not assemble the components without a spring shim on the cylinder head.
  19. Install the spark plug. Refer to Spark Plug Replacement .
  20. Install the valve rocker arms. Refer to Valve Rocker Arm and Push Rod Cleaning and Inspection .