383 Motor Failure. FML
383 Motor Failure. FML So, I had a very odd rattle noise in the car that I couldn't figure out. I pulled the accessory belt today and started the motor up, hoping it was a pulley bearing going bad.
NOPE. I noticed the crank pulley dancing around a bit, and shut it down. The pulley and the hub are both tight on the crank snout from what I can tell, but I can move the pulley itself up and down about 1/8 of an inch. I'm guessing that one or more mains is gone or spun. Other than the rattle, and the nasty rattle/grind when shutting the car down, everything else was fine. Oil pressure is great, the exhaust note seems normal, its not burning or leaking any fluids.
I'm guessing its going to at least need rod and main bearings and a crank......But I'm not even sure what parts I would need since I didnt build the motor. I found out that the previous owner of the car that the motor was bought from right here on LS1 tech, and here is the ad:
https://ls1tech.com/forums/parts-cla...w-3-000-a.html
I'm just sick to my stomach right now....I'm hoping that the motor just needs a crank and bearings, but so far my luck hasn't been that great. Any suggestions?
Oh yeah, and I think the main cause of this failure was because the person who put the motor in put the stock weighted flexplate on it...and its an internally balanced motor. It shook the hell out of the motor for almost 2 years, until i bought it this spring. A few weeks ago, I put a balanced flexplate on it and it cleared up the vibration completely, but apparently it was too late.... damage done.
NOPE. I noticed the crank pulley dancing around a bit, and shut it down. The pulley and the hub are both tight on the crank snout from what I can tell, but I can move the pulley itself up and down about 1/8 of an inch. I'm guessing that one or more mains is gone or spun. Other than the rattle, and the nasty rattle/grind when shutting the car down, everything else was fine. Oil pressure is great, the exhaust note seems normal, its not burning or leaking any fluids.
I'm guessing its going to at least need rod and main bearings and a crank......But I'm not even sure what parts I would need since I didnt build the motor. I found out that the previous owner of the car that the motor was bought from right here on LS1 tech, and here is the ad:
https://ls1tech.com/forums/parts-cla...w-3-000-a.html
I'm just sick to my stomach right now....I'm hoping that the motor just needs a crank and bearings, but so far my luck hasn't been that great. Any suggestions?
Oh yeah, and I think the main cause of this failure was because the person who put the motor in put the stock weighted flexplate on it...and its an internally balanced motor. It shook the hell out of the motor for almost 2 years, until i bought it this spring. A few weeks ago, I put a balanced flexplate on it and it cleared up the vibration completely, but apparently it was too late.... damage done.
Looks like Eagle cast crank. I know at one time they had machining problems on the thrust surface that was eating up bearings, might help explain crank movement while still maintaining oil pressure.
If mains did spin that can make a block not worth repairing, hope that is not the case just want you to be aware it is possible.
It was a motor built all on price and it showed in a short life. It sucks that you got burned rather than the guy who slapped together a POS in the first place.
Only way to know how bad it is is going to be to pull it apart, best case like you said is crank and bearings, good cleaning and that will require a rebalance too. Worst case would be spun mains and rods damaging the block and rods at which point all you have left is home ported heads, mediocre cam, intake and pistons.
If mains did spin that can make a block not worth repairing, hope that is not the case just want you to be aware it is possible.
It was a motor built all on price and it showed in a short life. It sucks that you got burned rather than the guy who slapped together a POS in the first place.
Only way to know how bad it is is going to be to pull it apart, best case like you said is crank and bearings, good cleaning and that will require a rebalance too. Worst case would be spun mains and rods damaging the block and rods at which point all you have left is home ported heads, mediocre cam, intake and pistons.
I really don't think this was the builders fault at all. I'm pretty sure it was the person who slapped this motor in. It made great power, its just I've spent all summer fixing little issues here and there that the person who put it in screwed up. I wouldn't think that I spun bearings, seeing as I have decent steady oil pressure. I guess we'll see when it gets cracked open. I already know a good shop that works with SBC's and can balance, clean, and if it needs it line hone the block.
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20$ says its an eagle crank.
Ive seen another one snap in half this year on a stroker engine. Eagle will leave you holding the bill even if its within warrenty.
EDIT: just read the forsale post...and it is an eagle crank! go ******* figure!
Ive seen another one snap in half this year on a stroker engine. Eagle will leave you holding the bill even if its within warrenty.
EDIT: just read the forsale post...and it is an eagle crank! go ******* figure!
Last edited by trilkb; Nov 3, 2011 at 06:45 PM.
Teching In
Joined: Apr 2009
Posts: 42
Likes: 0
From: Wilmington NC
On my 383 build I bought my rotating assembly separately. Forged flat-tops, forged 5.7 h-beam rods and a 200$ summit cast steal crank. i went with forged pistons and rods because they see quite a bit of force, obviously, but no need in getting a forged crank imho unless your gonna be putting down some serious numbers. With a proper install you should have no issues with a basic cast steal crank (again, imho) (going on 3 years pulling to 6800 with mine)
id go with a forged crank. Scat probably. Id just stay away from eagle. After what they did to a guy i know, ill never give them a dime of my money or a minute of my time. Ive never heard of an overkill forged crank being a "bad thing", and im sure you dont want to do it a 2nd time.
Oh yes, thats fine. I even thought the crank hub itself may have come loose, but you can move the whole front of the crank around. I guess we'll see whats what in the springtime, I'll tear it apart, and see if its saveable. I'm hoping for bearings, crank, and a line hone. I mean, the ****** still runs... LOL and I never even got a SES or a hiccup. Oil pressure is great too.
