Valve adjustment. How tight?
Thread Starter
Instructor
Joined: Nov 2013
Posts: 249
Likes: 0
From: Piedmont Missouri
Valve adjustment. How tight?
I've read all sorts of articles on hydraulic lifter valve adjustments on SBC engines. Also watched several YouTube videos. It seems like nobody agrees on how tight to go on valves after zero lash. I have a 69 L-46 and have some loose rocker arms. Some people say one full turn after zero lash, others say a 1/2 turn. One article said 1/4 turn, another 3/4 turn. Which is it? Thanks for any help.
Mark
Mark
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
IIRC, the factory setting is 1 full turn after "zero lash". However, for decades, "hot rodders" have been setting them between 1/2-3/4 of a turn, so they don't "pump up" as readily at higher RPMs.
Thread Starter
Instructor
Joined: Nov 2013
Posts: 249
Likes: 0
From: Piedmont Missouri
Thanks! I'll going with 1 full turn. No racing for me. Just trying to shut up the noisy valves.
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
Are you using "poly-lock" nuts, or the standard "crimped thread" nuts? If the latter, and they've been "adjusted" a few times, they won't lock on to the studs any longer, and you'll be adjusting them again.
Thread Starter
Instructor
Joined: Nov 2013
Posts: 249
Likes: 0
From: Piedmont Missouri
I just have the standard ones. Thanks, I'll change the nuts while I'm at it.
Drifting
Joined: Jun 2010
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From: Oxford Ohio
Drifting
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
I do them a 1/4 turn until they are all turned then another 1/4 and then another 1/4 to total 3/4. Then when it's running I back them off until I just barely hear them and tighten them 1/2 them go back over to 3/4 after the engine reaches running temp. I know, more work than is normally done, but that is the way I do them.
Most don't readjust while running. After you get used to it it's is easy and relatively fast. Rocker stoppers keep the oil from splashing all over the fender. I think lisle makes them. Probably from Jegs or Summit also.
Most don't readjust while running. After you get used to it it's is easy and relatively fast. Rocker stoppers keep the oil from splashing all over the fender. I think lisle makes them. Probably from Jegs or Summit also.
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
I do them a 1/4 turn until they are all turned then another 1/4 and then another 1/4 to total 3/4. Then when it's running I back them off until I just barely hear them and tighten them 1/2 them go back over to 3/4 after the engine reaches running temp. I know, more work than is normally done, but that is the way I do them.
Most don't readjust while running. After you get used to it it's is easy and relatively fast. Rocker stoppers keep the oil from splashing all over the fender. I think lisle makes them. Probably from Jegs or Summit also.
Most don't readjust while running. After you get used to it it's is easy and relatively fast. Rocker stoppers keep the oil from splashing all over the fender. I think lisle makes them. Probably from Jegs or Summit also.
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