61. Camshaft Cleaning and Inspection

Camshaft Cleaning and Inspection

Special Tools

J 7872 - Magnetic Base Dial Indicator

For equivalent regional tools, refer to Special Tools (Special Tools).

Cleaning Procedure

1. Clean the camshaft in solvent.
Warning: Refer to Safety Glasses Warning (Safety Glasses Warning).

2. Dry the camshaft with compressed air.
3. Cover the camshafts with a clean oil soaked towel in order to prevent corrosion.

Visual Inspection Procedure




1. Inspect the camshaft sprocket locating pin (2) for damage or wear.
2. Inspect the threads (3) for the camshaft sprocket bolt.
3. Inspect the camshaft lobes (1) and journals (4) for the following conditions:

* Excessive scoring or pitting
* Discoloration from overheating
* Deformation from excessive wear, especially the camshaft lobes




4. Inspect the left intake camshaft for the following additional conditions:

* Excessive wear on the sealing surface (1) for the camshaft seal
* Damage to the threads (2) for the water pump drive belt pulley bolt

5. If any of the above conditions exist on the camshaft, replace the camshaft.

Camshaft Measurement Procedure




1. With the camshaft in a suitable fixture, measure the camshaft for wear.




2. 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.




3. Measure the camshaft runout using J 7872 - indicator. Refer to Engine Mechanical Specifications (LD8) (Service Limits & General Specifications (VIN Y))Engine Mechanical Specifications (L37) (Service Limits & General Specifications (VIN 9)).




4. Measure the camshaft thrust wall width (1) for wear using an inside micrometer. Refer to Engine Mechanical Specifications (LD8) (Service Limits & General Specifications (VIN Y))Engine Mechanical Specifications (L37) (Service Limits & General Specifications (VIN 9)).
5. Measure the camshaft thrust wall surface (2) for runout using J 7872 - indicator. Refer to Engine Mechanical Specifications (LD8) (Service Limits & General Specifications (VIN Y))Engine Mechanical Specifications (L37) (Service Limits & General Specifications (VIN 9)).
6. If the camshaft is damaged or worn beyond specifications, replace the camshaft. No machining of the camshaft is allowed.




7. Measure the camshaft lobes for wear using the J 7872 - indicator.




8. Place the J 7872 - indicator with the indicator tip on the base circle (2) of the camshaft lobe.

1. Place the J 7872 - indicator dial at zero.
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.
3. The specifications for lift are as follows:

* Intake camshaft: 6.154 mm (0.2423 in)
* Exhaust camshaft: 5.944 mm (0.2336 in)

9. If the indicated measurement is significantly lower than these specifications, replace the camshaft or engine performance will be reduced.