nada

I have to replace a rocker arm nut that won't stay tight. I understand there is a procedure to quiet the rocker with the engine running. I did it last night but the darn nut "backed off" again. With the engine idling, I tightened the rocker nut until the tapping stopped. Then I backed it off again to make it tap. Following that, I tightened the nut until the tapping stopped and then turned the nut another 1/2 turn. I can't find this procedure in the "How to rebuild your small block Chevy" book. It only addresses adjusting the valve lash with the engine static. I'd appreciate the help or a link to this procedure guys.

Thanks, Rick

gravismaximus

you right on every thing, but i think its 1/4 turn. also to get it from backing off, put another nut on, thus stopping the first one from backing off. id do tha unless you just rebuilt it, and its the first time its back off. most will after a rebuild once or twice, mine did once but i check it again at its first 3,000, havent had any other probs with it scince.

nada

Thanks Gravis!

Rick

isosceles

1/4 turn on running engine worked for me. I had to buy one new nut too. Like dork, I used one of the nuts to fasten the valve spring compressor on all the valves when I was changing the seals. That nut in question didn't loosen up, but I only left it on for a day before I replaced it with a new one.

kobuzz

Might also check and make sure the stud isn't pulling out of the head. Been there, done that...

RMS73

After reading your first post I assume you have determine the stud is not loose, but the stud threads can be worn and not allow the nut threads to tighten against each other. Check how a new regular nut runs on the stud threads. If there is "slop" - the nut turns very easy and wobbles to the side then the stud threads are worn. You can double nut the stud, but the stud should be replaced.
Roger

70PurpleLS7

Your also using the proper lock nut I assume? The nuts have an oblong opening so they "lock" themselves, over a period of adjustments they lose their locking capability. Double nutting would be a temp fix, but not the proper one. Buy a new set of locking nuts, their only about $10.