How do you adjust the rocker arms on a 1972 Chevy 307?

Answer 1

First these are lifter that self adjusting ( hydraulic ). They are if necessary adjusted

with the nut that holds the Rocker Arms to the head casting,located in the middle

of the pressed rocker arm. Now this can get messy unless you have deflectors that can keep the oil under control,But if you do not mind and you do this one bank at a time ( just remove one valve cover at a time ), may be some fire retardant type of oil rag to keep the oil from catching 'FIRE'!! you start the engine.

if it runs and if the rocker arms are not TOOO tight and you have an idle then you

back off the nut on each arm so you hear the tapping sound for that valve. Slowly

turn in the nut until the sound goes away.No tap, tap sound. then this depends on the condition of the lifters some times 1/4 of a turn or as much as a full1and1/2 turns. But not often. you do this to each valve until all are done.Cover up 'put back the valve cover and repeat on the other bank. This may get the job done .Good luck!

To do this task with the engine turned off, crank the engine by hand until #1 is at TDC for compression. From this position you can adjust 1, 2, 5, & 7 intakes, and 1, 3, 4, & 8 exhausts. Rotate the engine one revolution so that #6 is up for compression, and adjust the rest of the valves.

To adjust: start with the nut loose enough to have some up and down motion in the pushrod between your thumb and forefinger, and tighten the nut until all endplay is removed. Preload the lifter with an additional 1/4-1/2 turn.