GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

    • J 23523-F Balancer Remover and Installer
    • J 5825-A Crankshaft Gear Remover

    Object Number: 188000  Size: SH
  1. Remove the engine front cover. Refer to Engine Front Cover Replacement .
  2. Important: Once the composite engine front cover is removed, do not reinstall the engine front cover. Always install a new engine front cover.

  3. Remove the crankshaft position sensor reluctor ring.

  4. Object Number: 11503  Size: SH
  5. Inspect the timing chain free play. Refer to Timing Chain and Sprockets Removal .
  6. Rotate the crankshaft until you complete the following actions:
  7. 4.1. The timing marks on both sprockets are aligned.
    4.2. The number one cylinder is at top dead center (TDC) of the compression stroke.

    Object Number: 330581  Size: SH
  8. Remove the camshaft sprocket bolts.

  9. Object Number: 330584  Size: SH
  10. Remove the camshaft sprocket.
  11. Remove the camshaft timing chain.

  12. Object Number: 11506  Size: SH
  13. Use the J 5825-A in order to remove the crankshaft sprocket.
  14. Remove the crankshaft balancer key, if necessary.

Installation Procedure

Tools Required

    • J 23523-F Crankshaft Balancer Remover and Installer
    • J 5590 Crankshaft Gear Installer

    Object Number: 387766  Size: SH
  1. Install the crankshaft balancer key in the crankshaft, if removed. The crankshaft balancer key should be parallel to the crankshaft or with the front of the crankshaft balancer key slightly lower.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Align the keyway of the crankshaft sprocket with the crankshaft balancer key.

  4. Object Number: 32066  Size: SH
  5. Use the J 5590 and a hammer in order to install the crankshaft sprocket.

  6. Object Number: 11503  Size: SH

    Important: Ensure that you align the camshaft and the crankshaft sprocket alignment marks.

  7. Align the camshaft and the crankshaft sprockets timing marks.

  8. Object Number: 330584  Size: SH
  9. Install the camshaft sprocket and the camshaft timing chain.
  10. Verify that the crankshaft sprocket is aligned at the 12 o' clock position and the camshaft sprocket is aligned at the 6 o' clock position.

  11. Object Number: 330581  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  12. Install the camshaft sprocket bolts.
  13. Tighten
    Tighten the camshaft sprocket bolts to 25 N·m (18 lb ft).


    Object Number: 188000  Size: SH
  14. Install the reluctor ring to the crankshaft position sensor. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .
  15. Install the engine front cover. Refer to Engine Front Cover Replacement .