Inspect the camshaft gear.
For rear gear train engines. Refer to Procedure 001-012 in Section 1.
For front gear train engines. Refer to Procedure 001-013 in Section 1.
Inspect the camshaft bushing. Refer to Procedure 001-01 0 in Section 1.
NOTE: Front gear train engines have a front camshaft bushing. Rear gear train engines have a rear camshaft
bushing. Some engines may be equipped with both.
Only inspect the camshaft bushing that is on the same end of the engine from which the camshaft was removed.
NOTE: Inspection of the rest of the camshaft bushings and camshaft block bores is not necessary, unless during
the inspection of the camshaft, damage was noted on the camshaft journals.
Clean the camshaft with solvents and dry with compressed air.
Inspect the valve lobes and bearing journals for cracking, pitting, or scoring.
Inspect the camshaft gear mounting surface on the camshaft to make sure the camshaft gear locating dowel
pin is in place and is not bent, sheared, or cracked.
For guidelines for reuse of cast iron camshaft and tappets, use the Camshaft and Tappet Reuse Guidelines in
Bulletin 3666475.
Edge Deterioration (breakdown) Criteria
The area of edge deterioration must not be greater than the equivalent area of a 2 mm [0.079 in] circle within ยฑ 20
degrees of the nose of the camshaft lobe.
Outside of the ยฑ 20 degrees of the nose of the camshaft lobe, the areas of edge deterioration must not be greater
than the equ ivalent area of a 6 mm [0.236 in] circle.
NOTE: If the camshaft shows any pitting or wear, remove and inspect the tappets before installing the camshaft.
Refer to Procedure 004-015 in Section 4. If a new camshaft is installed , new tappets must be installed.
