GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • EN 46105 Camshaft Locking Tool
    • EN 46111 Crankshaft Rotation Socket
    • EN 46112 Tensioner Retraction Pins
    • J 45027 Tensioner Tool

    Object Number: 1306381  Size: SH
  1. Ensure that the primary camshaft drive chain tensioner (3) is being installed.

  2. Object Number: 1306417  Size: SH
  3. Using the J 45027 , reset the primary camshaft drive chain tensioner plunger.

  4. Object Number: 1306418  Size: SH
  5. Install the plunger into the primary camshaft drive chain tensioner body.

  6. Object Number: 1306420  Size: SH
  7. Compress the plunger into the body and lock the primary camshaft drive chain tensioner by inserting the EN 46112 into the access hole in the side of the primary camshaft drive chain tensioner body.
  8. Slowly release pressure on the primary camshaft drive chain tensioner. The primary camshaft drive chain tensioner should remain compressed.

  9. Object Number: 1306422  Size: SH
  10. Install a NEW primary camshaft drive chain tensioner gasket to the primary camshaft drive chain tensioner.
  11. Install the primary camshaft drive chain tensioner bolts through the primary camshaft drive chain tensioner and gasket.
  12. Ensure the primary camshaft drive chain tensioner mounting surface on the engine block does not have any burrs or defects that would degrade the sealing of the NEW primary camshaft drive chain tensioner gasket.

  13. Object Number: 1578984  Size: SH
  14. Place the primary camshaft drive chain tensioner into position and loosely install the bolts to the block.
  15. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1306423  Size: SH
  16. Verify the proper placement of the primary camshaft drive chain tensioner gasket tab (1).
  17. Tighten

    1. First Pass
    2. Tighten the primary camshaft drive chain tensioner bolts to 5 N·m (44 lb in).

    3. Final Pass
    4. Tighten the primary camshaft drive chain tensioner bolts to 23 N·m (17 lb ft).


    Object Number: 1579326  Size: SH
  18. Release the primary camshaft drive chain tensioner by pulling out the EN 46112 and unlocking the tensioner plunger.

  19. Object Number: 1579327  Size: SH
  20. Verify the primary and left secondary camshaft drive chain timing mark alignments (1-12). Also refer to Camshaft Timing Drive Chain Alignment Diagram - Stage One.

  21. Object Number: 1306426  Size: SH
  22. Remove the EN 46105-1 from the rear of the left camshafts.

  23. Object Number: 1579328  Size: SH
  24. Using the EN 46111 , rotate the crankshaft and crankshaft sprocket from the stage 1 alignment position (1) to the stage 2 alignment position (2), 115 crankshaft degrees, in order to install the right secondary camshaft drive chain components.

  25. Object Number: 1306428  Size: SH
  26. Install the EN 46105-2 onto the rear of the left camshafts.

  27. Object Number: 946124  Size: SH
  28. Install the EN 46105-1 onto the rear of the right camshafts.