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Discussion Starter #1
Hey all. Well I thought I had the regular valvetrain tick, starting to think its a little more than that. It is worse when the motor is cold but it is always there. It is not the normal piston slap noise. It honestly sounds like the lifters bled down overnight. But it dosent go completely away when warm. It is most distinctive at arond 1300-2000rpm. I know there are a bunch of threads on the tick subject but no one has found a cause for the noise. I have already tried harland sharp rockers, but it didnt help. Well I am hoping that someone has found a fix for the loud ticking be it springs pushrods lifters or rockers but if not I will be tearing the heads off to have a look at it all. I will be replacing all of the valvetrain with comp cams pieces. car is an 02z QS with 40000 miles. I bought it used and it was not this loud at purchase. thanks all
 

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roadrash9r said:
Hey all. Well I thought I had the regular valvetrain tick, starting to think its a little more than that. It is worse when the motor is cold but it is always there. It is not the normal piston slap noise. It honestly sounds like the lifters bled down overnight. But it dosent go completely away when warm. It is most distinctive at arond 1300-2000rpm. I know there are a bunch of threads on the tick subject but no one has found a cause for the noise. I have already tried harland sharp rockers, but it didnt help. Well I am hoping that someone has found a fix for the loud ticking be it springs pushrods lifters or rockers but if not I will be tearing the heads off to have a look at it all. I will be replacing all of the valvetrain with comp cams pieces. car is an 02z QS with 40000 miles. I bought it used and it was not this loud at purchase. thanks all
I would just replace that valve-train anyways, especially on a used car, you might not know how hard it was driven.

Mine got a little noisier (at about the same milage) then a spring snapped and drove a valve through a piston, shattering that and destroying the block there are pictures in the gallery section of this site:

http://www.muchneeded.com/

Zed
 

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Yeah, the noise you're talking about seems to be a mystery. I've seen threads where guys have replaced everything in the valve train and it still persisted. This leads me to think it might be in the rotating assy. Maybe a piston rocking in it's bore (these pistons have very short skirts) or wrist pin. I have no idea. I have the noise as well as others but now I just ignore it. If the engine blows I'll let Chevy get me a new one, or maybe replace it with a 427! :)
 

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jub jub said:
Yeah, the noise you're talking about seems to be a mystery. I've seen threads where guys have replaced everything in the valve train and it still persisted. This leads me to think it might be in the rotating assy. Maybe a piston rocking in it's bore (these pistons have very short skirts) or wrist pin. I have no idea. I have the noise as well as others but now I just ignore it. If the engine blows I'll let Chevy get me a new one, or maybe replace it with a 427! :)
Drive till it blows!!!! I blew that BadAzz Engine up like a MOFO and chev came through and gave me a new one. Chev seems to be pretty good at helping if the problem is their fault, not like ford which is voiding cobra warantees for having the wrong width tires on.

Zed
 

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Discussion Starter #5
man zed that sucks!!!!! So your noise got louder too. If you look at the specs on the stock springs, they are barely able to support the ls6 cams lift. Thats it Im swapping it all. How hard was it to remove the motor. It looks alot easier than I thought in the pics. Probably not though. thanks for the info
 

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roadrash9r said:
man zed that sucks!!!!! So your noise got louder too. If you look at the specs on the stock springs, they are barely able to support the ls6 cams lift. Thats it Im swapping it all. How hard was it to remove the motor. It looks alot easier than I thought in the pics. Probably not though. thanks for the info
Pulling the motor isn't "completely" evil, though it does take time and it does suck.

Label every bolt, label every dangling wire, draw (and take) pictures of how things came off so you can get them back in the right places... the wires and tubes that bolt to the back and right side of the block are actually pretty confusing.

Getting it back in harder than taking it out. For both prodedures suspend the engine from an engine crane, and unbolt the suspension and from the tub, drop the cradel and suspension out as one peice and lift the engine out of the way... the oil pan on the block goes around the cradel not leaving enough room to pull the block out of the top without dropping the cradel. You can leave the AC pump, and brake lines in place by doing this (but the steering rack must come out). If you do it once, you can do it again a lot faster after... but I wouldn't try to make a habbit of it!

Zed
 

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Anyone that has owned some of the 80's Vettes with Tuned Port Injection will remember the ticking noise that the injectors used to make. Took me awhile to get used to that with the first one. Never had a single problem with the car though.


Chris
 

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Ill bet $$$ its a combo piston slap with the tick of fuel inj. Drive it like you want and see if anything develops. I dont think it will Enjoy. :guiness:
 

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If the car runs well, then it is not rockers, pushrods or lifters. Trust me you would know. It would run horrible. Rockers and pushrods are easy to check. Lifters are much bigger problem.

My guess, is probably a loose header gasket/loose headers bolts. I am more than 50% sure just by reading your post. My have come loose half a dozen times. Easily checked as well. See if the bolts are loose. Yes, this will make a crapload of noise and torque will feel off(It will be).

The factory Felpro gaskets suck and wear out. Use the 02-04 stainless GM gasket on CLEAN surface(Header/Head, header locking nuts, washer, liquid header seal.

You should make sure these locking nuts are tight every six months or less. I go over my car constantly. Yesterday, it was the lower radiator hose on my Rod Davis radiator and my DRM Race oil distribution block that is above my oil filter(trying figure out how to fix that one easily). I am sure next month it will be something else.

As far as piston slap, that is another story entirely.
 

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In the same boat and scared!!!

Well, I am at a loss here. I have a 2001 Z06, and started hearing a very disturbing sound from the top end of my motor at just 39K. After reading the forums, I suspected a faulty valve spring was my culprit. I found my number 2 cylinder was running about 30lbs light on compresssion and lost 24% on a leak down test. At this point I was still thinking valve spring. Did a wet leak down test with oil in the cylinder, had vey similar results - about 19% on leak down. Here is where it gets tricky, my mechanic tour down the valve train and called me to say everything on the top end was in good shape and he suspects I blew a ring and the engine should be replaced. The electrode on the number 2 plug as acutally bent to the side. The engine actually runs fine, minus the loud ticking. Obviosly I have not tried to push the car since this started. Any advice? BTW, quote I got for crate motor and install was $9k - Ouch. If a new motor is needed, wouldn't a rebuild be much cheaper and bore this baby out for a few more ponies? I really don't want to go over $3k to fix this, dont' want to and can't afford to. Any advice would be appreciated.
 

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As you probably know, there were oil burning issues with some of the 01's and that is probably what you're seeing. If you want a rebuild on the cheap, you might consider a set of aftermarket pistons. They are .005" oversize and will reqire the cylinders be honed to fit. Boring of the cylinders is not possible because of the thin liners. Add a set of rod and main bearings and call it a day. Depending on your mechanic and what he charges, you should be able to get it done for 3k.
 

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Thanks Jub. Have you had any experience with any corvette shops in the Atlanta area? I want to get this done right so that I am never in this same situation again.
 

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whataz06 said:
Thanks Jub. Have you had any experience with any corvette shops in the Atlanta area? I want to get this done right so that I am never in this same situation again.
There are two places that i know of that I would trust, MTI of Atlanta and Lamar Walden. Both have an outstanding reputations and are knowledgeable with the LS-6.

You should go over to http://www.peachstateposse.com and join. They're an Atlanta based group and will be able to point you in the right direction.
 

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What I would do.

If it is out of warranty,
buy a forged 348 short block from A&A if the car starts running bad for $3,500. Other wise just drive it. The stock cylinders are not round in any of the stock Zee motors. So I am not really surprised that you one off by 5%.

To show you the difference in what I am saying, my 430 cid produced 1/5 the emissions of stock Z06 at idle and almost nothing at 2,500 rpms. This is with B&B shorties, the stock cats and a Borla XR race exhaust(no mufflers).
 

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finally getting back to my Z06, valve spring was not the culprit

Well, finally got back around to trying to figure out what the heck the ticking was and why I am losing compression in my # cylinder. With the head off, I was very surprised to see that the #2 piston was melted. Injector seems to be fine, but for some reason appears this cylinder was shorted gas. The valve springs, valves all seem to be in good shape. The piston will come out today, taking it out through the pan, had to wait for the engine top mount bracket tool to come from MAC. Anyone seen this before? What would cause this cylinder to not get fuel.

link to pics of the motor
 

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I would say one of two things. Either the coil in the injector is open or there is a open in the harness. I believe, although I'm not positive that a short anywhere would produce a fault code. I would have that injector tested.

BTW, I've never seen nor heard of that happening on an LS1/6. :screwy:
 

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Whataz06, What's the plan for the rebuild? Just wondering if you are going with a short block or What? Very good photo's of a dead piston. I think I would like to change the injectors anyway for a blue printed /flowed set. Please keep us informed.

D.J.
 

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Discussion Starter #19
Its all done!!!!

Well got it finished took me 3 days after all the parts arrived. Changed everything. Put Comp lifters, comp pushrods, comp 918 springs, com adj timing chain, Thunder racing 224x112 cam, Ported oil pump, port and polished heads with manley race flow undercut valves, haltech cobra carbon air bridge, throttle body bypass, air box mod, flp header, X pipe, high flow cats, and borla 4 tip stingers, PCMFORLESS.com PCM. All at one time and honestly it could have been done in two days. I did all the work myself with the help of a friend for the big pieces. I am an Jet engine mechanic by trade so It might take longer for someone just starting out. It really was easy and I cant imagine how these shops are charging so much for installs. If anyone is in the panama city or pensacola area in florida look me up I will do heads cam engine swaps ect for A LOT less than what the big boys are asking. It really is easy (time consuming) but if you take your time and have access to a lift (I do) anyone can do it. Now back on the subject, The lifter noise is gone, with that said the valve train is noisier than stock due to the cam profile. But it is all a little noisy not just one area. I only have 100 miles on this so we will see if it comes back... knock on wood. :crazy: As for the Butt dyno :cen: geeeze this thing rocks!!!! I love my Z. sound like a mean V8 at idle then like a lambo screaming at 6 grand. I honestly believe it has to do with the cam. Sorry so long all figured you would want to know. Thanks again for all the help and info. Let me know if you have any questions. Also big :thumb: up to Brian at PCMFORLESS.com Nailed the tune the first time. No driveability issues what so ever, no codes, really awesome.
 
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