89tang

iTrader: (15)

Need some advice here on what to do, first to tell ya what the car was doing. When we bought the car last march i heard a noise it sounded like a tick from an exhaust leak i figured since it had an aftermarket catback on it then that's what it was no biggie right. So within a week i get it home and start tightening up bolts but the tick didn't go away.

Here's a video of the noise i'm talking about
http://www.ezarchive.com/89tang/Albu...49281/99ta.mpg

Anyways i told the g/f to take the car back to the dealership and have it looked at. She did and they took it to a shop to have the rocker arms changed on the drivers side they said it was a rocker arm. Get it back still same noise they said LS1's are known to be noisy not to worry about it. I didn't argue mainly cause the 30day warranty was almost up i think that's why the kept the car so long so that would happen. Me and most everyone that listened to the car thought it was a lifter i planned on modding the car i'll change them out. Fast foward to this week i decided to start modding it since i had vaca. this week i'm doing a cam, intake, headers swap and a few other things. I get the motor tore down to the shortblock tonight and i take the drivers side head off, there's a newer felpro gasket on it so new that it didn't even leave anything on the head when i peeled it off hmmmmmmm take the lifters out i didn't notice anything until i took the passanger side head off the lifters in the driver side are new, someone has tried to fix this before now i'm wondering wtf the noise is and that's probably why the car was traded. If it's a cam, rod, crank bearing it's only a matter of time before it goes out, but the oil pressure stayed steady just like it should. And the noise is only there from 1500-2500rpm or so.

I'm debating on ripping the shortblock out and having it refreshed i just don't have the money right now, or just tossing all the mods on and saying screw it run it till it blows which it's hard to tell when that could be.
What do you guys think about the noise and everything?

89tang

iTrader: (15)

I think i figured out what the problem is, i wedged myself into the cowl area and looked down the lifter hole at the cam lobes on the drivers side. One of lobes looks like it had fatigue in the metal or something and has a bunch of pits all over it not a few there's alot of them. So hopefully this is my problem and it'll be solved with the cam swap i'm going to do. Now that i remember there was always some metal shavings stuck to the oil pan drain plug and this is most likely where they came from.

Has there ever been any problems like this before with the stock cams in these motors? When i take it out tomorrow or friday i'll take some pic's of the cam lobe an post them.

vettenuts

iTrader: (4)

Check the lifter roller too. Sounds like someone has been floating the valves based on your description.

89tang

iTrader: (15)

Well the roller on the lifter looked fine other then a small line that runs around it due to i'm guessing the pit's in the cam lobe. But it's a newer lifter i have no idea what the stock lifter looked like. It's the only lobe on the cam though that has anything wrong with it plus it's an A4 and it was never modded, cause the passanger head gasket is the stock gasket. There's also a slight groove wore into the valve stem where the rocker arm sit's nothing noticeable unless you shine it in the light just right, and you could see the wear pattern on the rocker arm was different from the rest. But again probably from the messed up cam lobe.

FRDnemesis

iTrader: (19)

I highly doubt that was the problem. Sounded more like a exhaust leak at the manifold or a weak/collapsed lifter. Pits in a cam lobe are doubtful to make that sound.

89tang

iTrader: (15)

And i highly doubt it was a manifold or exhaust leak of any kind since there was no exhaust leak, considering the all header gaskets showed no sign of leaking neither did the air pipe and EGR gaskets. Plus all the bolts were tight i triple checked everything after we bought it.These aren't just pits it looks like a dog nawed on the cam lobe. I say pits cause it's the best way i can explain it.

Also the lifters were NEW so it wasn't a "weak or collapsed lifter". I guess you could consider it like driving on a paved road and a gravel road. Which one is going to cause noise when you drive over it.

Rebelord

iTrader: (2)

could have been that lifter. But also sounds much like an exhaust leak.

89tang

iTrader: (15)

Hard to say what is making the noise the lifter or the cam causing the lifter to make the noise. It is NOT an exhaust leak i know the difference, an exhaust leak would get louder with rpms this noise stopped at 2500rpm or when the oil pressure would go up.

here's some pic's for everyone





As you can see there is a pretty large groove wore into the cam about 1/64th's deep where the roller on the lifter rode on the cam maybe not quite that deep but it is noticable, also not to mention the metal missing between the groove. But yeah you guys are probably right it's prolly just an exhaust leak or a bad lifter

Haans249

iTrader: (24)

yea, i think this was definitely the cause of your noise!

Haans

89tang

iTrader: (15)

Well that's what i think also, luckily a cam swap was in the plans anyways this week. Now if GMPD would just get my parts to me so i can put this bitch back together lol. I guess while i'm waiting on those i'll throw the converter in.

Rebelord

iTrader: (2)

So it wasnt an exhaust leak, but it was a lifter. So calling bs on some of us saying its a lifter is kinda bs in itself. not trying to start **** but that would cause an serious lifter noise.
on a lighter note. If you can, try to take a good look at your cam bearings to make sure there isnt any pitting or scoring on them from the metal that came off the old cam. If you have time waiting, this would be a good time to throw in the stall and do some preventative maintenance to make sure everything else it good to go before you get it all back together and all hell breaks loose.

Ski

89tang

iTrader: (15)

I don't believe it was a lifter if you look at the cam i think you can see it wasn't the lifter that caused it atleast i don't think so. I figure had it been the lifter the whole cam lobe woulda looked like that not just that one spot. Am i right or am i wrong? And like i said the lifter i took out was newer and it looked new there was no sign of wear on it except a small line that ran around it i'm guessing from the place in the cam. The reason i said BS was because i stated a few times it wasn't an exhaust leak and i stated the lifter in question that the others thought was weak or collapsed was infact a newer lifter. Even after saying there were pits or chunks of cam missing it was still said that wasn't the problem it was an exhaust leak or bad lifter. Obviously the guy that had it before we did tried to fix the problem, he thought lifters too and changed the lifters on the drivers side but it didn't work still made the noise so he traded it off because he never thought to look at the cam.

And yes i'm putting a stall in this week, and new oil pump new this new that. Should be fun for me all week . Any person taking a motor apart for more power or for anything really should know to do preventative maintence.