GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 8062 Valve Spring Compressor
    • J 37979 Valve Spring Compressor Adaptor

    Object Number: 262025  Size: SH
  1. Use a steel square, and measure the deviation of the valve spring.
  2. Valve Spring Deviation
    2.0 mm (0.079 in)

  3. If the deviation of any valve spring is greater than the specified maximum, the valve spring must be replaced.

  4. Object Number: 262024  Size: SH
  5. Use a Vernier caliper, and measure the free length of the valve spring.
  6. Valve Spring Free Length
    36.83 mm (1.4500 in)

  7. If the free length of any valve spring is not within the specifications, replace the valve spring.

  8. Object Number: 235418  Size: SH
  9. Use a spring tester, and measure the tension of the valve spring at the specified installed height.
  10. Valve Spring Tension
    20.9-23.5 kgf (lbf) at 32.6 mm (1.28 in)

  11. If the installed tension of any valve spring is not within specifications, replace the valve spring.
  12. Inspect the valve spring seating surface of the valve spring seats for wear or for gouging. Replace the seats, if necessary.
  13. Temporarily install the valves into the cylinder head.
  14. Use the following steps in order to measure valve runout:
  15. 9.1. Apply a small amount of Prussian blue on the entire valve face. Seat the valve, but do not rotate the valve. The Prussian blue traces on the valve seat are an indication of concentricity of the valve seat.
    9.2. Clean all traces of Prussian blue.
    9.3. Apply a small amount of Prussian blue on the valve seat, and repeat the check. The traces of Prussian blue on the valve face indicate valve face concentricity.
    9.4. Recondition the valve seat, or replace the valves, if required.
  16. Inspect the valve spring seating surface of the valve spring seats for wear or for gouging. Replace the seats, if necessary.
  17. Temporarily install the valves into the cylinder head.
  18. Use the following steps in order to measure valve runout:
  19. 12.1. Apply a small amount of Prussian blue on the entire valve face. Seat the valve, but do not rotate the valve. The Prussian blue traces on the valve seat are an indication of concentricity of the valve seat.
    12.2. Clean all traces of Prussian blue.
    12.3. Apply a small amount of Prussian blue on the valve seat, and repeat the check. The traces of Prussian blue on the valve face indicate valve face concentricity.
    12.4. Recondition the valve seat, or replace the valves, if required.
    12.5. Install the spring seat.
    12.6. Use a valve seal installer, and install the new valve seals. Completely seat the seals on the valve guides.

            Important: Be careful when installing the valve seals. Do not tap or hit the seal installer with a hammer, only install the seals by hand.

    12.7. Install the spring.
    12.8. Install the retainer.

    Object Number: 373669  Size: SH
  20. Compress the valve spring. Use theJ 8062 and theJ 43184 .

  21. Object Number: 373663  Size: SH
  22. Install the valve keepers.
  23. Slowly release theJ 8062 from the assembly of the valve and of the spring.
  24. Use a plastic faced hammer and lightly tap the valve stem tip and inspect for proper valve key seating.