Tools Required
J 7872  Magnetic Base
Dial Indicator Set
- Inspect the camshaft journals, lobes and bearings for the following
conditions:
 
| •  | Excessive scoring or pitting | 
 
| •  | Discoloration from overheating | 
 
| •  | Deformation from excessive wear, especially the camshaft lobes | 
 
- If any of the above conditions exist on the camshaft, replace
the camshaft.
 
- If any of the above conditions exist on the camshaft bearings,
replace the cylinder head.
 
- Measure the camshaft journals for diameter and out-of-round using an
outside micrometer.
 
| •  | If the diameter is smaller than 26.948 mm (1.061 in),
replace the camshaft. | 
 
| •  | If the out-of-round exceeds 0.022 mm (0.0009 in),
replace the camshaft. | 
 
- Install the camshaft bearing cap in the cylinder head without
the camshaft.
 
- Measure the camshaft bearings using an inside micrometer.
 
- Subtract the camshaft journal diameter from the bearing diameter.
This will provide the running clearance.
 
If the running clearance exceeds 0.041-0.085 mm (0.0016-0.0033 in)
and the camshaft journals are within specification, replace the cylinder head.
- Measure the camshaft lobes for wear using the following procedure:
 
| 8.1.  | With the camshaft supported in v-blocks, set up the J 7872 
 with the indicator tip on the base circle
of the camshaft lobe. | 
 
| 8.2.  | Rotate the camshaft until the indicator tip is at the highest
point on the lobe. This reading is the lift(1) of the camshaft lobe. | 
 
| 8.3.  | The specifications for lift are as follows: | 
 
RPO LD8 - VIN Y
|    •  | Intake camshaft lift: 8.6 mm (0.339 in). | 
 
|    •  | Exhaust camshaft lift: 8.6 mm (0.339 in). | 
 
RPO L37 - VIN 9
|    •  | Intake camshaft: 9.4 mm (0.370 in). | 
 
|    •  | Exhaust camshaft: 8.6 mm (0.339 in). | 
 
- If the indicated measurement is significantly lower than these
specifications, replace the camshaft or engine performance will be reduced.