The rocker arm shaft bracket bolts and nuts should be tightened to 20 ft. lbs. before adjusting the valves.
- Unscrew the retaining bolts and remove the cylinder head cover.
- Rotate the crankshaft until the No. 1 or No. 4 piston is at TDC of the compression stroke.
- Start with the intake valve on the No. 1 cylinder and insert a feeler gauge of the correct thickness (intake: 0.010", exhaust: 0.014") into the gap between the valve stem cap and the rocker arm. If adjustment is required, loosen the locknut on top of the rocker arm and turn the adjusting screw clockwise to decrease the gap and counterclockwise to increase it. When the proper clearance is reached, tighten the locknut and then recheck the gap. Adjust the remaining three valves in this step (see illustration) in the same manner.
- Rotate the crankshaft one complete revolution and then adjust the remaining valves accordingly.