97lt1camaro

iTrader: (3)

Does this sound like normal roller rocker noise? Its only on one side (passenger) and doesnt sound very good.

If i take a screwdriver and put it on the rocker studs, 2 and 8 sound like clanking almost and are quite prominent with there sounds. Im wondering if i have some lifter issues to deal with.

The Ticking is easily heard by the headers when listening under the car, can clearly hear it in the tubes. No no exhaust leaks are present. All lifters are pushing oil.

Disregard the shitty start, battery is nearly dead and the alt isnt hooked up.

http://www.youtube.com/watch?v=kZs3dI2vxKU

comments, advice, anything is welcome at this point, im at my wits end.

pboxfun

iTrader: (2)

I was gunna say check around your header flange and see if its leaking around there somewhere because mine almost sounded the same but it was just a header leak. But you said you have no leaks so it can't be that.

BlackBird87

iTrader: (6)

did you pop the vc off and look at whats going on?

97lt1camaro

iTrader: (3)

As far as i can tell yes, there arent ANY exhaust leaks. I will confirm again tomorrow, but im 99.9% positive there isnt any.

I had it backfire through the intake 2 times yesterday also which i still have no idea why.

This is really starting to get disheartening . I just want to drive it already.


Yes, The valve covers have been off more times then id like already. Everything appears to be in order, nothing looks bent. Valves have been adjusted 3 times engine running and still no change. They appear to be moving the same distances.

It recently just had a entire top end build. Lifters, rockers, new cam, heads, gaskets, ewp, injectors, tune etc...

SoxXpupPeT

iTrader: (34)

wow thats bad. pop off the valve covers and see what you find. Mine are loud too but that doesnt sound quite right. are you running the proper length pushrods ?

97lt1camaro

iTrader: (3)

Ive had them off and nothing seems out of the ordinary unfortunatly

Yes we measured the pushrods properly before installing and setting lash. I believe i may be SLIGHTLY SLIGHTY off center towards the header side if not by big amount by any means.

|||| If that was the top of the valve. Im pretty much right where the red one is marked.

SoxXpupPeT

iTrader: (34)

Hmmm thats about where mine are. What brand rockers are they ? and are they full rollers ? when was the last time you set valve lash ?

97lt1camaro

iTrader: (3)

Comp Pro mags NSA. I bought them used. So that may be the issue in itself, ive moved a few of them over to the drivers side, but it doesnt seem to follow.

Set valve lash on tuesday with engine running, backed off till they made noise, slowly tigthened the poly till the noise stopped, the 1/4 turned and locked into place.

97lt1camaro

iTrader: (3)

Well we pulled the intake again today and replaced the lifters on the passenger side where the noise was. No such luck, did however notice that cylinder 4 seems to be making the noise, and just so happens that one took almost a full 15 minutes to actually pump up and start oiling. Im really at a loss for words here.

I took the car for a spin on the highway, pulls nice but every once in a while feels like it misses for just a slight second. Im wondering if thats the knock sensor pulling timing cause of all the godamn noise the passenger side is making.

Im also getting a intake backfire every once in a while, so im wondering if its either running way rich (sure smells like it at idle) or if im just getting a lean condition when im on the go pedal.

Tear, im almost wishing i left well enough alone

LilJayV10

iTrader: (39)

If it's backfiring through the intake you could have an intake valve that's a little tight, but you say you are only putting 1/4 turn preload on them. I have found 1/2 is a good comprise.

Are the lifters new?

Don't give up on it man, I know it's tough sometimes not too.

97pontta

iTrader: (10)

What brand of lifters did you use on the new setup? Is everything matched and setup correctly as far as valve lift and spring combo on the new cam/heads setup?

I've never been a fan of adjusting the rockers with the engine running, I just could never get a consistent last setting on each cylinder. I prefer getting the lifters pumped up and adjusting them by hand/rotating the engine by watching the intake/exhaust pushrod and adjusting the approach rocker.

Depending on what brand of lifters you use 1/2 preload past zero lash may be too much. With my replacement crane lifters I found them to work the best at only 1/8 turn preload past zero lash. Your setup may be different and is something you would have to play with to see what works best for you. Having too much preload isn't good.

97lt1camaro

iTrader: (3)

I thought about having a intake valve too tight but we've adjusted them numerous times, and with only a 1/4 turn past clacking while running. The intake backfire isnt consistent either, seems like it will only do it once in a while and usually its with no load, just on idle and revving.

Lifters are brand spanking new, all of them are oiling. They are Comp Cams 850-16 i believe, LT/LS OE replacement.

The instructions in the paper that came with the lifters suggested 1/2 turn preload past zero lash. However we adjusted the drivers side 1/4 turn also and that side just makes normal sewing machine like noise where as the passenger side ticks like a bastard.

850-16 Comp Lt/Ls OE replacement lifters. Heads were done by one Mr Lloyd Elliot, i HIGHLY HIGHLY doubt this is a issue on his end.

We've adjusted them with engine running, and engine off after running. Doesnt seem to make a difference, still has noise .

Im going to fire it up today and start pulling plug wire's to see if i can narrow it down to atleast a cylinder.



Has anyone every heard of a lifter bore being ******* up in the block causing a lower oil pressure at that lifter then the rest?

Suggestions and comments welcome, id like to get this thing running like a top.

Thanks

RamAir95TA

iTrader: (2)

Honestly I'd pull out those 850s and put in some LS7s...

97lt1camaro

iTrader: (3)

I had contemplated that the 2nd time the intake came off,but i just cannot see why the passenger side is so much louder compared to the drivers side. It just doesnt make sense. Ive read about them and people seem to have good things to say about comps replacement lifters. I severely doubt that i got 2 boxes of bad lifters.

I will mention that i actually did have a VERY SLIGHT ticking on the passenger side before the top end build, but im not sure how much of a bearing that would have on this car now.

JAKEJR

In my GM 96 LT1 FSM in the section addressing excessive valve train noise, GM lists insufficient lifter preload as one of the primary causes.

Many, many guys seem to gravitate toward the less preload end olf the scale, apparently based on something they've read somewhere. These seem to be the same guys who end up complaining about too much noise.

Crane warns that running too little lifter preload can result in lifter(s) failure.

For my 96 LT1, in the FSM GM recommends ONE FULL TURN +/- 1/4 TURN. Now that's for GM's stock lifters. IIRC CompCams recommends 1/2 turn of preload from ZERO LASH for their lifters.

I recommend you try increasing the lifter preload to 3/4 TURN, rather than decreasing it. Use the IC/EO method, as CompCams recommends.

Jake

97lt1camaro

iTrader: (3)

I shall try that tonight. The question i have now is that how much preload is going to be too much and starting hurting performance/parts.?

97lt1camaro

iTrader: (3)

jakejr, you are now my favoritest person on this forum. Thankyou good sir.

hhhdurrrrrrrrr.

Adjusted valves on passenger side to 1/2 past lash. Brought the car down off the ramps and fired her up. No noise until the oil was hot and up to temp and if i revved it up to about 3 or so the noise would be gone for about 10 seconds then return.

Diagnosis: Oil is thinning out and causing lifter to lose its prime slightly as shown by revving engine causing oil pressure to rise removing said noise from lifter cavity for brief period.

Prognosis: Will be switching to a 40 weight or possibly even 50 weight, probably 40, and readjusting ALL valves to 3/4 past zero lash.

The reason i didnt pick up on this earlier when adjusting was that the car was already HOT and we didnt rev the engine or let it run long enough to notice what i noticed today.

http://www.youtube.com/watch?v=CSD6Bx348eU

http://www.youtube.com/watch?v=X6_10vv0W9s

wysemunky

iTrader: (2)

sounds good!

lt1formula275

what kind of roller rocers are they. i put a cheap set on my old lt1 and one of the rockers made an awful racket. it turns out the little roller had a catch or something like it didnt roll smooth. u could turn it with ur fingers and it make a grinding sound. so u could check that.