GM Service Manual Online
For 1990-2009 cars only

Special Tools

    • J 22102 Front Cover Aligner and Seal Installer
    • J 42846 Crankshaft Protector Button

Removal Procedure


    Object Number: 470814  Size: SH
  1. Remove the engine front cover. Refer to Engine Front Cover Replacement.
  2. Align the timing marks on the camshaft and crankshaft sprockets.
  3. Remove the camshaft sprocket bolts.
  4. Remove the camshaft sprocket and timing chain.

  5. Object Number: 639535  Size: SH
  6. Install the J 42846 (1) into the end of the crankshaft.
  7. Remove the crankshaft sprocket using a suitable three jaw puller.
  8. Clean and inspect the timing chain and sprockets.

Installation Procedure


    Object Number: 65850  Size: SH
  1. Use the J 22102 in order to install the crankshaft sprocket.
  2. Align the keyway of the crankshaft sprocket with the crankshaft pin.

  3. Remove the J 22102 .
  4. Rotate the crankshaft until the crankshaft sprocket alignment mark is in the 12 o'clock position.

  5. Object Number: 470814  Size: SH

    Note: 

       • Install the camshaft sprocket with the alignment mark in the 6 o'clock position.
       • The sprocket teeth must mesh with the timing chain in order to prevent damage to the camshaft retainer.
       • Do not use a hammer to install the camshaft sprocket onto the camshaft. To do so may damage the camshaft.

  6. Install the camshaft sprocket and timing chain.
  7. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 677756  Size: SH
  8. Look to ensure that the crankshaft sprocket is aligned at the 12 o'clock position and the camshaft sprocket is aligned at the 6 o'clock position.
  9. Install the camshaft sprocket bolts.
  10. Tighten

    1. Tighten the camshaft sprocket bolts a first pass to 30 N·m (22 lb ft).
    2. Tighten the camshaft sprocket bolts a final pass to 30 N·m (22 lb ft).
  11. Install the engine front cover. Refer to Engine Front Cover Replacement.