Camshaft Inspection

CAMSHAFT INSPECTION









Tool Required:
J 26900-12 Dial Indicator
J 26900-13 Magnetic Base


Inspect
^ Sprocket.
^ Keyway and threads.
^ Bearing surfaces and lobes for:
- Wear.
- Galling.
- Gouges.
- Overheating (Discoloration).

Important
^ Do not attempt to repair the camshaft, replace it if damaged.
^ If a new camshaft is installed, all valve lifters must be replaced.



Measure
1. Bearing journals.
^ With a micrometer, measure diameter and run-out.
If out of specification, replace the camshaft.

2. Camshaft lift.
A. Lubricate the camshaft bearings with GM Camshaft and Lifter Prelube p/n 1052365 (or equivalent).
B. Carefully set the camshaft on "V" blocks or between camshaft centers.
C. Install J 26900-12 and J 26900-13.
D. Measure camshaft journal runout and lobe lift (Figure 57 and 58).
If out of specification, replace the camshaft.


Important
^ If a new camshaft is being installed, add Camshaft and Lifter Prelube GM p/n 1052365 (or equivalent) to the engine oil.
^ Coat cam lobes with Camshaft and Lifter Prelube GM p/n 1052365 (or equivalent).