Thread: Fresh BBC; Noisy Valvetrain

Tweet

First, sorry about the Gear Drive question earlier....I didnt know you guys would beat it to death like you did...

I have a fresh rebuilt BBC, hydraulic, stamped 1.7:1 steel rockers, and my valve train seems to be making an excessive amount of noise on one side of the motor. I re-tightened all of the header bolts (thinking is was a header leak making noise) and that did not help. I have tried adjusting 1/4 to 1/2 turn, and even 3/4 of a turn past "zero lash" and when I went 3/4 it seemed to quiet the noise somewhat (these were static adjustments).

I removed the valve cover, fired her up, and put a barnyard stethoscope (broom stick) to each rocker stud and some are definitely "rap, rap, rapping" and some are nice and quiet, so I then tried the hot adjustment but cannot determine when or if my adjustments were making any difference due to engine noise and the fact that more than one lifter is knocking. I didnt want to tighten too much for fear of pushing a valve into my piston. Is that a concern or will I notice a change in idle quality before something like that happens?

I found this procedure posted by Denny and was wondering if anyone (Denny esp.) would care to try and explain it differently?

With the engine running, you back off the rocker adjustment until you here it tapping. (One at a time). Next, make sure your socket does not bottom out over the adjusting nut.
Tighten until you hear the tapping just get quite.
Now, read this careful: Put your ratchet and socket on the adjusting nut, not bottomed out, and get the handle positioned so you know where each Quarter turn will stop.
Turn, tighten very slowly, only put a small amount of pressure on the ratchet, and you will feel it go easy, stop, go easy, stop.
This is happening because each time the rocker goes up and down, it takes up space, and pushes the oil out of the lifter(bleeds off).
Then, let it stablelize, (when engine speed picks back up).
Then, go for the next quarter turn, just like the first quarter turn you did.
After you set the last one, the engine will then be breathing in syc. You will actually hear this.

The engine starts great, runs great (a little on the rich side as I noticed from all of my plugs), pulls about 19" of vac at 700rpm.

I am trying to determine if I am adjusting wrong or if I have some bad lifters. People have told me that BBC valve trains are noisy but I dont think what I am hearing on the motor is correct.

Thanks all...

running about 75psi at start-up and 60psi or so after it warms up...

Any suggestions Denny other than tearing it back down or things I could check before I resort to dissassembly? I cant believe I would have several go bad right away.

Thanks Denny...

Looking ahead...say I replace the lifters. Should I order another identical kit and replace only as many as necessary or just buy single replacement type hydraulic lifters? Installed currently is a Lunati cam and lifter set.

Originally Posted by DennyW

If you can pin point the ones making noise, you can just replace them. ...

Let's assume they will not replace them without a charge (they might though, I hadnt thought of that !), Can I stick a standard GM hydraulic lifter in there in it's place? I can buy those down at the corner store.

Sorry, Not trying to take up your morning...I appreciate you taking time to address this problem with me.

if the rockers are used they get a 1/2 moon mark worn in them by the valve stem and they will go in and out of lash so if you can hook your nail in the bottom of the rocker arm then they junk .are you runing long slot rockers how much lift do you have ?the lunati is re box lifters try to get a set of jonson lifter they i think are the best after holley took over lunati hard to say where them lifters came from

Hi Pat, I am not running much lift, only .515/.530 and the rockers are oem stamped steel. I dont know what the long slot rockers are that you are referring to.

The corner store sells Melling rockers for 3.99/ea and I was thinking of using those. This isn't a serious duty motor. May never see 6000. Will probably pick up some replacement stamped rockers at the same store?

Quick follow up question....

On a fresh motor, how can I identify "abnormal" lifter wear or defective lifter after I pull the intake ? Will it be painfully obvious? Remember, only about 7 hours of run time on the motor and the one that was making noise was solid (pumped up) after I shut the motor down.

Any problem with replacing the lifter(s) in question since the cam has been broken in already ? I have read that you should not install new lifters on an "old" cam....
Going to tear it down tonight and start the process.

I have always heard that you shouldn't install old lifters on a new cam......or that you shouldn't ever re-use lifters unless they were going back on the same lobe of the same cam they were removed from. That isn't your question, but I think you can install a new lifters. You might have to do a break-in again. Someone else here will know better than me.

Your gear drive is causing your valve train noise. Gear drives are great!!!!
Just kidding, I am just hoping to revive this thread a little, (I am curious to hear the opinions of others on lifter wear, and the other items in 65Caynes latest post) and the whole gear drive discussion seemed to get a lot of attention before. So, forget everything said about gear drives and let me know what you think about Caynes valve train dilema.

Thanks 65NY for dusting off the post.

FYI, I replaced all of the rockers and the new ones adjusted alot nicer and feel alot smoother than the old ones (the old ones had a lot of wear on the valve stem contact surface, they were from another set of heads).
I fired it up, overall it sounds nicer but I still have the one tick tick tick...at 1/2 rpm which I suspect is the #8 intake.

I am going to pull it apart to inspect but as I said, the one that is ticking was solid (pumped up) when I shut the motor down. I am certain that is the one because I pushed on all of the rockers and the noise muted considerably when I put my hand on that one (not an easy task btw...maybe I was pushing too hard).

.500 lift should require long slot on most SBC's I've seen,don't know about BBC.Also,take you an old set of valve covers and cut a slot down the top to see and get the socket in and loosen til slight tick and tighten to stop.Go very slow and do the rev.procedure Denny suggests. Not saying you don't have a bad lifter or two but some lifters don't like to cooperate after getting them too tight.

I'll inspect the old rocker but I dont think it is a slot problem. FAYLUR, what do you mean exactly by the reverse procedure Denny suggested? I cant back it off till it taps because it is already tapping....I went a good full turn (while the motor was running) past normal adjustment and the ticking did not stop. I was afraid to go any further down on the nut. Incidentally, I could not quiet the ticking by pushing on the rocker after that extra turn. I dont know if that indicates anything.

Thanks for the reply FAYLER. I appreciate yours and everybody elses input.

My problem SEEM's to be a lifter but why would it be nice and pumped up after I shut the motor down as I stated earlier? That doesnt make sense to me and makes me hesitate to pull the motor apart for it.

The procedure I was describing was if the lifters hadn't been adjusted 'properly' yet. Noise could be from other areas.

you need more than 500 on a big block to need long slots if you looking for answer ? on your lifters you could have some junk in the lifter like denny said .about putting one new lifter in that hole yes you could do it if the lifter is not wipe out the face of the old lifter looks good you could try a new lifter i would say you have 50/50 chance and it may not work. i would take the new lifter and sand the face a bit with wetdry 600 grit paper with WD40 and see if it takes. sanding it will help the new lifter brake in use moly on the face of it make sure it turns free in the bore oil only on the body not moly .the moly should only be on the face of the lifter

I pulled the lifters on the "noisy side" of the engine last night including the #8 intake which I found to be "the ticker" and all of the lifters are rock solid when I push on them on the bench. None of them exhibit any unusual or excessive wear on the bottom end and all of my cam lobes (upon preliminary inspection) look good. On the lobes, there is a little trail along each one that gets slightly wider as is goes over the nose. This, to me, is normal. I will measure for lift tonight.
Most of the lifters have a barely noticeable, almost like a "rasberry" (for those who've had smallpox vacc), wear pattern. That, to me, is also normal. The rest of them are hard to determine...nothing unusual though.

I'll sand the new one before I install. Anything else I should look for now that I have it apart and based on what I have described?

Side note: can you re-use intake gaskets?