Insert a 3/4 in. drive breaker bar or ratchet into the square hole in the center of the crankshaft pulley. Bar the engine over.
Rotate the crankshaft until the number one piston is at top dead center.
Check whether the No.1 and No. 6 cylinder pushrods rotate freely. Both intake and exhaust valve pushrods must be able to rotate freely.
With the valves of No. 1 cylinder closed, it is now possible to check and adjust valves 1I, 1E, 3I, 6E, 7I and 10E. See Figure
, step 1.
Starting with the first cylinder, adjust the valve lash as follows:
Check the alignment of the valve bridge contact to exhaust and intake valve stems. Valve bridge adjustment can be made by loosening the lock nut, and turning the adjusting screw until contact is made with the valve stem.
Place valve bridge in holding tool J 41569. Tighten lock nut to 18 - 22 lb ft (25 - 30 N m).
Install valve bridge on guide and recheck alignment, readjust if needed.
Measure the valve lash by inserting a feeler gage between the rocker arm and the valve bridge. Use a .016 in. (0.406 mm) feeler gage to measure intake valve lash. Use a .020 in (0.508 mm) feeler gage to measure exhaust valve lash. See Figure
2.Rocker Arm Assembly
Valve Lash Adjustment
The valve lash is correctly adjusted when, after tightening the locknut, a slight resistance is felt when the feeler gage is removed.
To adjust, loosen the locknut, and adjust the clearance using the adjusting screw
Tighten the locknut, and check the lash. Correct as necessary.
Bar engine over 360 in direction of engine rotation.