Tools Required

J 7872  Magnetic Base Dial Indicator

1. Clean the camshaft in solvent.
CAUTION: Refer to Safety Glasses Caution in Cautions and Notices.
2. Dry the camshaft with compressed air.
Fig 1: View Of Camshaft Damage
Courtesy of GENERAL MOTORS CORP.
3. Inspect the camshaft retainer plate for damage.
4. Inspect the camshaft for the following conditions:
   • Camshaft bearing journals (1) that are:
     • Worn
     • Scored
     • Damaged
   • Worn camshaft lobes (2)
   • Damaged sprocket bolt threads (3)
   • Damaged sprocket pin (206)
Fig 2: Measure Camshaft Journals With Micrometer
Courtesy of GENERAL MOTORS CORP.
5. Measure the camshaft journals with a micrometer. Refer to Engine Mechanical Specifications .
Fig 3: Measuring Camshaft Runout
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6. Measure for excessive camshaft runout using J 7872  .
   1. Mount the camshaft in a suitable fixture.
   2. Use the J 7872  in order to measure for a bent camshaft. Refer to Engine Mechanical Specifications .
7. Replace the camshaft if runout exceeds specifications.
Fig 4: View Of Engine Block Bearing Bores
Courtesy of GENERAL MOTORS CORP.
8. Inspect the camshaft bearings (1-5), for wear or damage.
9. Replace the camshaft bearings if necessary. Refer to Camshaft Bearing Removal  and Camshaft Bearing Installation .