- Visually inspect the cam for wear or damage. Replace if necessary.
Set the front and rear journals on V-blocks. Check the camshaft runout on each journal by turning the camshaft in clockwise direction and measure the camshaft runout. If runout exceeds 0.0012in (0.03mm) replace the camshaft.
Check the cam lobe height at the two points as shown in the figure. Measured height should be between 1.7658-1.7737 inches (44.852-45052 mm). If lobe height is not within specifications, replace the camshaft.
Measure wear of the journals in X and Y directions at the two points as shown. The diameter should be 1.1787-1.1797 inches (29.940-26.965 mm) and should not measure more than 0.002 inch (0.05mm) out of round. If either measurement is not within specifications, replace the camshaft.
Measure the oil clearance of the camshaft and camshaft caps as follows:
- Remove any oil or dirt from the journals and bearing surface.
- Set the camshaft onto the cylinder head.
- Position Plastigage on top of the journals of all cam caps in the axial direction.
- Place camshaft caps according to the cap number and arrow, and tighten them to 13-20 ft. lbs. (18-26 Nm) using the proper sequence.
- Loosen the camshaft cap bolts in the proper sequence.
- Carefully remove the camshaft caps.
- Measure the oil clearance at each cap.
- Oil clearance should be 0.0014-0.0033inches (0.035-0.085 mm) and should not exceed a maximum of 0.0059 inch (0.15 mm).
If the oil clearance indicated by the Plastigage measuring is not within specifications, replace the camshaft and/or the cylinder head.
Using a dial indicator measure the camshaft end play. Camshaft end play should be between 0.003-0.004 inches (0.08-0.10mm), with a maximum of 0.008 inches (0.20mm). If it exceeds the maximum, replace the camshaft and/or the cylinder head.
Visually inspect the Hydraulic Lash Adjuster (HLA) face for signs of wear or damage. Replace as necessary.
NOTEA wear pattern that resembles a horizontal bar on the lash adjuster indicates normal wear.
Hold the HLA between your thumb and forefinger. Squeeze the HLA; if it compresses, replace the lash adjuster.
Removal & Installation
- Before servicing the vehicle, refer to the Precautions section.
- Properly relieve the fuel system pressure.
- Drain the coolant into a suitable container.
Remove or disconnect the following:
Negative battery cable
Install or connect the following:
Camshafts into the cylinder head. The exhaust camshaft has a steel dowel pin at the rear for the camshaft position sensor