Camshaft and Bearings Cleaning and Inspection

Tools Required 

J 7872  Magnetic Base Indicator Set

1. Measure the camshaft journals with a micrometer.

   If the camshaft journals are not within specifications, replace the camshaft. The measurement should be 47.655-46.858 mm (1.8462-1.8448 in). If the measurement is not within specifications the engine camshaft must be replaced.

   Fig 1: Measure Camshaft Journals

   Courtesy of GENERAL MOTORS CORP.
2. Measure the camshaft runout using J 7872  .
   1. 2.1. Mount the camshaft in V-blocks between centers.
   2. 2.2. Use J 7872  to check the intermediate camshaft journal.
3. If the runout exceeds specifications, the camshaft is bent and should be replaced. If the camshaft journals are more than 0.025 mm (0.0010 in) out-of-round, then replace the engine camshaft.
   Fig 2: Measure Camshaft Runout Using J 7872

   Courtesy of GENERAL MOTORS CORP.