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hotGTO
09-26-2010, 07:04 PM
Just bought the Stealth TT, after getting on it a few times one night (no real launches, just a few fun runs around 75%) and a long drive, it sounded like a few marbles rattling around in the motor at idle, and oil pressure down very low... rattling sound was BAD and would come and go on a small rev getting bad at idle... This was on fresh oil with less than 1000 miles on the oil... I was sure it is a spun bearing, but it was not as bad after I restarted the car hours later or the next day, and I put new fresh oil in the next day and it sounds normal now and my oil pressure is still there, but at high RPMs the engine will raise hell so I am just taking it easy on her until I can get it looked at. So is this the beginning of my spun bearing mod? How long could I baby it before it is gonna sound like the youtube video of those rednecks revving the crap out of the TT and it sounded like pounding the block with a hammer, and I lose all oil pressure? Also, if it's already too late and I need a rebuild, what can I hurt by still driving it until it dies? Thanks!

PS: oil pan is not dented.....

vroom4
09-26-2010, 11:42 PM
Yea sure sounds like a spun bearing. Drive that bitch till it locks up, just put in 20-50 with like 25% lucas and you wont even hear the knock. I put almost 300 miles on mine with less than 10 psi at WOT. Lots and lots and lots of AWD burnouts finally sent the rod through the pan.:lol:

Austin@STM
09-27-2010, 01:12 AM
It is up to you how long you go for, the damage is already done, it deffinately sounds like a spun bearing. If you keep going the metal will go through the engine, and can damage the heads, cams, basically everything that oil goes through. If you stop now there may be some salvagable parts and may cost you less. Your best bet is to tear it down now and examine the damage, or at least park it until you can.

hotGTO
09-27-2010, 01:28 AM
When I changed the oil, I saw no metal in the oil, but I do hear a very light rod knock... I just want to know if I baby the motor how many miles to expect to get out of it before it really starts banging?

hotGTO
09-27-2010, 01:33 AM
And, unfortunately, I have never torn into an engine, so even though I want to rebuild it myself, I would not know what I am looking at so it would take me forever to figure it all out and do it right... :(

blindmist
09-27-2010, 12:55 PM
I am just going to say it so it has been said. I spun a bearing, drove it for 120 miles, I was about 200ft from my grandparents where I was going to leave it to trailer it home. I was at about 3000RPMs when the rod went out the back of the block. There is really no rebuilding a block with a hole in it. Just saying.

hotGTO
09-27-2010, 01:27 PM
Would a new short block fix the spun bearing problem, or would I need more on top of that?

Austin@STM
09-28-2010, 01:48 AM
Would a new short block fix the spun bearing problem, or would I need more on top of that?

If you dont drive it anymore, chances are you will be ok with a short block. You will need to get the heads cleaned, and decked. You will want a new oil pump, oil cooler, wash out the oil filter housing and anything oil goes through. Be 100% sure everything is CLEAN. It is a bit more involved but that gives you an idea.

PM me if you have any questions.

hotGTO
09-28-2010, 05:21 AM
I know everyone wishes they could get away with just changing the bearings, and I am the same... lol... But in all seriousness, I think I really have caught this before it has done major damage because while I can hear the rod it is so faint that I really do have to listen and feel for it... I am sure when I drop the pan I will find at least one bearing that is starting to fail or has failed, but it's not hammering the block yet, and I still have good oil pressure, it wouldn't hurt to do just bearings and oil pump as long as there is no metal in the oil, would it? I mean the outcome could end up the same, but isn't it worth a try if I caught it this early?

hotGTO
09-28-2010, 12:33 PM
Thanks, Steve! Hmmmm.... Does the hybrid datalogger that works on the 94 also work on a 91? I probably need a bigger fuel pump if I am getting detonation. To be honest, the thought about detonation has crossed my mind, and now that you have offered that opinion, I will definitely be looking into that problem before calling anything fixed!

Edit: I won't be able to drop the pan to examine the bearings until the weekend but I will post up what I find...