GM Service Manual Online
For 1990-2009 cars only

Tool Required

J 7872 Magnetic Base Dial Indicator

  1. Clean the camshaft in solvent.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Dry the camshaft with compressed air.
  4. Inspect the camshaft for the following conditions:
  5. • Worn, scored, or damaged bearing journals
    • Worn camshaft lobes
    • Damaged sprocket pin

    Object Number: 35212  Size: SH
  6. Measure the camshaft journals with a micrometer.
  7. Refer to Engine Mechanical Specifications .

  8. Measure for a bent camshaft or excessive camshaft runout using J 7872 .
  9. 5.1. Mount the camshaft in V-blocks between centers.
    5.2. Use the J 7872 in order to measure for a bent camshaft.

    Refer to Engine Mechanical Specifications .

  10. Replace the camshaft if runout exceeds specifications.
  11. Inspect the camshaft bearings and bearing cap surfaces for the following:
  12. • Wear
    • Scoring
    • Overheating from lack of lubrication
  13. Inspect the bearing clearances with gauging plastic.
  14. Refer to Engine Mechanical Specifications .

  15. Inspect the camshaft for excessive end play.
  16. Refer to Engine Mechanical Specifications .

  17. The camshaft bearing surfaces are machined into the cylinder head and are not serviceable.