Camshaft Measurement Procedure

WARNING: This page is about a different variant/trim than selected.

Fig 1: Supporting Camshaft

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Fig 2: Measure Camshaft Journals With Micrometer

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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.

Fig 3: Measuring Camshaft Runout

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Measure the camshaft runout using J 7872 . Refer to Engine Mechanical Specifications .

Fig 4: Measuring Camshaft Thrust Wall Width & Surface Runout

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Measure the camshaft thrust wall width (1) for wear using an inside micrometer. Refer to Engine Mechanical Specifications .
Measure the camshaft thrust wall surface (2) for runout using J 7872 . Refer to Engine Mechanical Specifications .
If the camshaft is damaged or worn beyond specifications, replace the camshaft. No machining of the camshaft is allowed.

Fig 5: Measuring Camshaft Lobes For Wear

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Fig 6: Identifying Camshaft Lobe Dimensions

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Place the J 7872 with the indicator tip on the base circle (1) of the camshaft lobe.
1. Place the J 7872 dial at zero.
2. Rotate the camshaft until the indicator tip is at the highest point on the lobe. This reading is the lift (3) of the camshaft lobe. Refer to Engine Mechanical Specifications .
3. If the indicated measurement is significantly lower than these specifications, replace the camshaft or engine performance will be reduced.