GM Service Manual Online
For 1990-2009 cars only

Special Tools

EN-422 Installer

For equivalent regional tools, refer to Special Tools.

  1. Install NEW camshaft seal rings.
  2. Note: Coat with MoS 2 lubricating paste. Refer to Adhesives, Fluids, Lubricants, and Sealers


    Object Number: 2027632  Size: SH
  3. Install the intake camshaft.
  4. Note: Note the identification marking on the camshaft bearing cover.

  5. Install the 4 intake camshaft bearing cover number 2-5.
  6. Caution: Refer to Fastener Caution in the Preface section.

  7. Install the 8 intake camshaft bearing cover bolts and tighten in a spiral from the inside to the outside to  8 N·m (71 lb in).
  8. Note: Coat with MoS 2 lubricating paste. Refer to Adhesives, Fluids, Lubricants, and Sealers.


    Object Number: 2027633  Size: SH
  9. Install the exhaust camshaft.
  10. Note: Note the identification marking on the camshaft bearing cover.

  11. Install the 4 exhaust camshaft bearing cover number 6-9
  12. Install the 8 exhaust camshaft bearing cover bolts and tighten in a spiral from the inside to the outside to  8 N·m (71 lb in).
  13. Note: Sealing surfaces must be free from oil and grease.

  14. Clean sealing surfaces of the first camshaft bearing support and the cylinder head with a suitable tool.
  15. Clean oil duct from any sealant residue.

    Note: 

       • It is essential to ensure that no sealant is applied outside the marked sealing areas.
       • The grooves adjacent to the sealing surfaces must remain free from sealant.

    Note: Sealing surfaces must be free from oil and grease.

  16. Apply surface sealant to sealing surfaces of the first camshaft bearing cap thinly and evenly.
  17. Check valve clearance and adjust if necessary. Refer to Valve Clearance Adjustment.
  18. Position the first camshaft bearing cap on the cylinder block and tighten the bolts approximately to  2 N·m (18 lb in).

  19. Object Number: 2027009  Size: SH

    Note: No sealant may reach the camshafts.

  20. Install the first camshaft bearing cap.
  21. Note: Note installation sequence 1-4.

  22. Install the first camshaft bearing cap bolts and tighten to  8 N·m (71 lb in).

  23. Object Number: 1945794  Size: SH
  24. Install 2 NEW sealing rings to the camshafts.
  25. Tighten the seal ring with EN-422 installer  (3) on the camshaft until this is in contact with the cylinder head.
  26. To install, use camshaft sprocket bolt (1) in conjunction with shims (2) with a total thickness of approximately 10 mm.
  27. Remove the EN-422 installer  (3).