GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • EN 46330 Timing Belt Tensioner Retaining Pin
    • J 8433 Pulley Puller
    • J 41478 Crankshaft Front Oil Seal Installer
    • J 41558 Crankshaft Sprocket Remover
    • J 41665 Crankshaft Balancer and Sprocket Installer
    • J 41816-2 Crankshaft End Protector
    • J 45059 Angle Meter

Removal Procedure

Notice: Do not turn the crankshaft assembly after the timing chain has been removed in order to prevent damage to the piston assemblies or the valves.


    Object Number: 1658175  Size: SH

    Notice: Do not turn the crankshaft assembly after the timing chain has been removed in order to prevent damage to the piston assemblies or the valves.

  1. Remove the oil pump. Refer to Oil Pump, Screen, and Crankshaft Oil Deflector Replacement .
  2. Remove and discard the camshaft sprocket bolt (206).
  3. Remove the camshaft sprocket (205) and timing chain (208).

  4. Object Number: 1658178  Size: SH
  5. Remove the bolts (231) and timing chain tensioner (232).

  6. Object Number: 1658180  Size: SH
  7. Use the J 41816-2 (1), the J 41558 (2), bolts (3), and the J 8433 (4) in order to remove the crankshaft sprocket.

  8. Object Number: 1658182  Size: SH
  9. Remove the crankshaft sprocket (207).

  10. Object Number: 156149  Size: SH
  11. Remove the crankshaft sprocket key, as required.

Installation Procedure


    Object Number: 156149  Size: SH
  1. Install the key into the crankshaft keyway, if previously removed.

  2. Object Number: 1272887  Size: SH
  3. Tap the key (122) into the keyway until both ends of the key bottom onto the crankshaft.

  4. Object Number: 1658182  Size: SH
  5. Install the crankshaft sprocket (207) onto the front of the crankshaft. Align the crankshaft key with the crankshaft sprocket keyway.

  6. Object Number: 1658237  Size: SH
  7. Use the J 41478 (1) and the J 41665 (2) in order to install the crankshaft sprocket.
  8. Install the sprocket onto the crankshaft until fully seated against the crankshaft flange.

  9. Rotate the crankshaft sprocket until the alignment mark is in the 12 o'clock position.

  10. Object Number: 1658249  Size: SH
  11. Compress the timing chain tensioner guide and install the EN 46330 .
  12. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1658251  Size: SH
  13. Install the timing chain tensioner (232) and bolts (231).
  14. Tighten
    Tighten the timing chain tensioner bolts to 25 N·m (18 lb ft).


    Object Number: 1658265  Size: SH

    Important: 

       • The sprocket teeth and timing chain must mesh.
       • The camshaft and the crankshaft sprocket alignment marks MUST be aligned properly.

  15. Install the camshaft sprocket (205), timing chain (208), and bolt (206).

  16. Object Number: 1658268  Size: SH
  17. Inspect the sprockets for proper alignment. The mark on the camshaft sprocket (1) should be located in the 6 o'clock position and the mark on the crankshaft sprocket (2) should be located in the 12 o'clock position.

  18. Object Number: 1658271  Size: SH
  19. Remove the EN 46330 .

  20. Object Number: 1658274  Size: SH
  21. Tighten the camshaft sprocket bolt.
  22. Tighten

    1. Tighten the camshaft sprocket bolt a first pass to 75 N·m (55 lb ft).
    2. Tighten the camshaft sprocket bolt a final pass an additional 50 degrees using the J 45059 .
  23. Install the oil pump. Refer to Oil Pump, Screen, and Crankshaft Oil Deflector Replacement .