Camshaft

Fig. 22 Checking Cam Lobe Height:

1. Set front and rear journals on V-blocks and check camshaft runout. If runout exceeds .0012 inch (.03mm), replace camshaft.
2. Check camshaft for wear or damage, replacing as necessary.
3. Check cam lobe height at two points as shown in Fig. 22, then compare as follows:
a. On SOHC engines, height should be 1.6163 inch (41.054mm) and must not be less than 1.608 inch (40.854mm) for intake, or should be 1.6257 inch (41.293mm) and must not be less than 1.6178 inch (41.093mm) for exhaust.
b. On 1989-91 DOHC engines, height should be 1.5976 inch (40.580mm) and must not be less than 1.5898 inch (40.380mm) for intake, or 1.5935 inch (40.475mm) and must not be less than 1.5856 inch (40.275mm) for exhaust.
c. On 1992 DOHC engines, height should be 1.5874 inch (40.320mm) and must not be less than 1.5800 inch (40.120mm) for intake, or 1.5873 inch (40.318mm) and must not be less than 1.5794 inch (40.118mm) for exhaust.

Fig. 23 Measuring Camshaft Journal Diameters:

4. Measure journal diameters in X and Y directions at two points as shown in Fig. 23, then compare as follows:
a. On SOHC engines, diameter of Nos. 1 and 4 should be 1.9268-1.9274 inch (48.94-48.955mm) and diameter of Nos. 2 and 3 should be 1.9258-1.9266 inch (48.915-48.935mm). Out of round must not exceed .0012 inch (.03mm).
b. On DOHC engines, diameter of Nos. 1 and 4 should be 1.1768-1.1797 inch (29.890-29.965mm) and diameter of Nos. 2 and 3 should be 1.1756-1.1785 inch (29.860-29.935mm). Out of round must not exceed .0012 inch (.03mm).
5. On SOHC engines, measure camshaft and cylinder head oil clearance as follows:
a. Remove any oil or dirt from journals and the camshaft bore.
b. Measure camshaft bore diameter, which should be 1.9297-1.9303 inch (49.015-49.03mm).
c. Subtract journal diameter from bore diameter. Oil clearance of Nos. 1 and 4 should be .0024-.0035 inch (.06-.09mm) and Nos. 2 and 3 should be .0031-.0045 inch (.08-.115mm).
d. If clearance exceeds .0059 inch (.15mm), replace camshaft or cylinder head.

Fig. 24 Camshaft Identification. DOHC Engine:

Fig. 25 Applying Plastigage To Camshaft:

Fig. 26 Camshaft Cap Bolt Tightening Sequence (Right):

Fig. 27 Camshaft Cap Bolt Tightening Sequence (Left):

Fig. 28 Measuring Camshaft & Cylinder Head Oil Clearance:

6. On DOHC engines, measure camshaft and cylinder head oil clearance as follows:
a. Remove any oil or dirt from journals and the camshaft bore.
b. Measure camshafts on cylinder mark according to its identification mark, Fig. 24.
c. Position plastigage on top of journal in journal axial direction as shown in Fig. 25.
d. Install camshaft caps according to cap number and arrow, then torque in sequence shown in Figs. 26 and 27 to 21-24 ft. lbs.
e. Loosen camshaft cap bolts in reverse order of tightening sequence, then measure oil clearance as shown in Fig. 28.
f. If clearance is more than .006 inch (.15mm), replace camshaft or cylinder head.
7. Measure camshaft endplay, measurement should not exceed .008 inch (.20mm).
8. On SOHC engines, if endplay is more than specified, replace thrust plate or camshaft.
9. On DOHC engines, if endplay is more than specified, replace camshaft or cylinder head.