I recently finished up my lsx swap and everything was going good until I heard this nasty screeching noise. At first I thought it was my power steering pump because the high pressure hose was leaking. I replaced it and the sound was still there. I ran the car without the belt and the sound did not go away. I thought it was the ati pulley so I put the stock pulley and the sound went away. The next day I let the car idle for about 20-30 minutes(oil pressure at cold start is 60psi then after a while it goes down to 35-40psi I'm running the Melling 10296) before I went for a 3 mile ride around the neighborhood. As I was pulling up to my driveway the screeching noise came back. There is no metal shavings in the oil. I took out the timing cover see if anything was rubbing but nothing. Right now I'm in the process of removing the cam to check the bearings. I have been searching on all the forums and YouTube to find a similar sound or problem but I have had no luck. If anyone knows what this could be or has had similar issues let me know how it was fixed. Here is a YouTube link of the sound on the stock pulley with the belt on the car turns off bc I has not been tuned yet.

http://www.youtube.com/watch?v=KnEhXMFjM4U&sns=em

Thanks,

Ben

 

I think it is a pulley bearing. Sound went away momentarily when you revved the engine because hub load reduced from change in belt tension.

 

Before you tear it down run it without the accessory drive (remove the serp. belt)see what that does I'm sure you will find it is probably not internal to the engine. You could also locate it with a mechanics stethoscope. I've even seen a faulty belt cause the most horrendous screeching noise.

 

He stated he ran it without the belt already and the sound did not go away.

Are you sure that it's coming from the front area? Did you just install the transmission?

 

The transmission is freshly rebuilt. When the screeching noise happens I press the clutch and it doesn't affect the noise in anyway, that's why I Kind of ruled that out. As soon as I get this cam out and rule out the bearings(although if it were a bad bearing I would see shavings of metal in the oil which I don't) I believe I'm going to have to pull out the motor and inspect the brand new pilot bearing, flywheel, and clutch. Which were all brand new. I'll keep you guys updated to see what I find.

 

you said that you replaced the pulley and the sound went away - was this with the belt off and pulley replaced?

also the three mile drive- you say that after you came back it started making that noise again- did you pull the belt off and see if the sound was still there after the noise came back?

 

After putting the stock harmonic balancer on I let it idle for a good 20-30 minutes and no noise. I took it on that 3 mile drive and that's when the noise started coming back. I took the belt off and no change the noise was still there the video was with the belt on but it's the same noise with the belt off. The noise started happening when we were at the tuners shop and it was about to go on the dyno. I opted out of the dyno tune bc my power steering hose was leaking a lot and I didn't want the pump to lock bc I thought that's where the noise was coming from so booked an appointment for a future date.

 

Ahh okay - gotcha. Yea then my next guess would be bearings.

 

Yeah I missed that part, HMMM I wonder if he installed a double roller timing chain. From my understanding that can cause interferance with the oil pump without shimming.

 

No double roller timing chain. The car does it only after its warmed up and running for a while. I'm in the process of dropping the engine and tranny right now.

 

No change with the clutch in or if you're moving?
Mine has a very slight "metal spinning" sound until I press in the clutch. Considering that I have everything new between the engine and trans I'm just waiting to see if it all settles in... It's hardly a noticeable noise and only when it's in neutral with the clutch released.

 

Oh man sorry about that, I guess this will be an interesting fix.

 

Could be a lifter.

 

Not sure what you have done, several options via google search. one being
http://www.ls1.com/forums/f7/squeali...perate-165916/

Ended up being the throttle body gasket on backwards so that the gasket was covering up the opening for the idle air sensor.
Always worth a try on google and ls1 tech in case this doesnt fix your problem.

 

Took the cam out and checked out all the bearings they all looked good. I took out the oil pump(Melling 10296) and I noticed that the bolt to change the spring was stripped indicating it might have been used and returned. I don't have Torx bits to open it up but will get some tomorrow first thing in the morning. I'll keep you guys updated. I think I might have found the culprit.

 

One more thing you could look at if you have a dry rocker arm it can cause some awful squealing.

 

Changed the pump had the car idling had no screeching for a while up until I took it for a drive. Back to the drawing board to try and figure out what is wrong.

 

Try this, I had it happen on a Ford truck once with a Cleveland engine in it. Engine made the most awful screeching.

 

Any ideas what could have caused this? Not even 5 miles on the car.

 

Yikes! Looks like you found your noise. I'm going to assume you haven't been riding your clutch like a noob?

Clutch is slipping, either it isn't fully engaging (pressing hard enough), or not fully releasing. On your test drives did you get on it hard enough to feel any slipping? Easier to tell the higher the gear you're in.

Or is it hard to shift, not letting the pressure off the syncros completely. Without releasing completely the clutch would effectively be slipping during gear changes.

I'd go with clutch not holding, is thus slipping and overheating the crap out of itself, which is why you only get the noise once things warm up.

 

Oh my, that is gonna hurt the wallet. Maybe bad throw out bearing to boot.

 

I never really got on it and never went past 3rd gear on the street. No hard shifts everything was smooth. A buddy of mine said that the throw out bearing might not have been releasing all the way. Everything was brand new ordered from tick so if it's a faulty throw out bearing that caused this I hope they can warranty it. If not there goes my hopes for a nitrous kit haha

 

Could be the TO bearing, though the only one I heard do that had a ton of miles and didn't matter what the temp was. But with it all apart, you should be able to tell if something is up with the bearing.

 

Bearing looked good. No scuffs or anything of that sort. I'm still going to replace it just incase though. Still waiting on monster to analyze the damaged parts.