metal in motor, carbon on pistons
06-09-2010, 12:48 PM
#1
metal in motor, carbon on pistons So I got this LT1 complete, intake to oil pan with all accessories. Guy tells me he got it from his friend who was going through a divorce, supposedly rebuilt 15-20k miles ago, couldn't get the title so parting it out, etc.... Says it has JE pistons in it. Well looking at it, it had been rebuilt, Felpro gaskets, new freeze plugs, and there are what appear to be JE pistons in it. Did anyone else make pistons like the JE's? The big deal with the pistons is there is a ton of carbon build up on all of them, what likely caused this? I heard I could clean it off with a hard plastic scraper?
Now onto my second issue with this motor. Guy says when he drove it home he didn't notice any strange sounds, says the car was really torquey, etc... Things looked good until I went to take the heads off. On the headbolt closest to the firewall under the valve covers, if you take them off in sequence it would be the first bolt you pull, I found metal. Actually all the oil left on the heads had metal in it! Where did this most likely come from? Most of the metal was on the passenger side head, although I found some on the very front bolt on the driver side, I suppose diagonally opposite from the bolt on the passenger side.
I had someone tell me that if an engine was rebuilt it could have metal in the oil from break in, but wouldn't this be excessive??
There was also this piece of metal in the same spot, looked like a half circle with a bit of a twist in it, and some squiggly piece of metal.
So wondering where the metal more than likely came from, and why so much carbon? The plugs were black as night I pulled out of this thing!
Want to solve the mysteries and figure out where I should go from here.
Oh yeah and they said during the rebuild they had put in a Lt4 oil pump, didn't that just have a different spring in it or something?
Now onto my second issue with this motor. Guy says when he drove it home he didn't notice any strange sounds, says the car was really torquey, etc... Things looked good until I went to take the heads off. On the headbolt closest to the firewall under the valve covers, if you take them off in sequence it would be the first bolt you pull, I found metal. Actually all the oil left on the heads had metal in it! Where did this most likely come from? Most of the metal was on the passenger side head, although I found some on the very front bolt on the driver side, I suppose diagonally opposite from the bolt on the passenger side.
I had someone tell me that if an engine was rebuilt it could have metal in the oil from break in, but wouldn't this be excessive??
There was also this piece of metal in the same spot, looked like a half circle with a bit of a twist in it, and some squiggly piece of metal.
So wondering where the metal more than likely came from, and why so much carbon? The plugs were black as night I pulled out of this thing!
Want to solve the mysteries and figure out where I should go from here.
Oh yeah and they said during the rebuild they had put in a Lt4 oil pump, didn't that just have a different spring in it or something?
06-09-2010, 01:10 PM
#2
That "squiggly thing" looks like a portion of a heli-coil. The rest looks like bearing material, if all the piston tops and spark plugs are intact. How's the inside of the oil pump look?
....on second thought, it could also be pieces of a trashed lifter. Have you looked at them?
....on second thought, it could also be pieces of a trashed lifter. Have you looked at them?
06-09-2010, 01:39 PM
#5
HOLY metal batman...wtf Corey it seems like you have the some really bad luck. Not to sound like a dick but hell man your always having horror stories like this. EIther way that bottom pics squiggely thing can be anything, is it copper, steel or aluminum.
2- is that the bearing below that squiggely piece?
If you scrape off the carbon on a piston you can visibly see the piston part number and then you can find out what you have.
Carbon build up can be from them never really beatin up on the car and only driving short mileage everyday and/or a oil problem.
I would tear down that engine and bring it to a machine shop to check everything over with a mic and plasitgauge. Something is very iffy about that engine. sorry bro but it happens.
Pull of some of the rod caps I bet you will find your problem
2- is that the bearing below that squiggely piece?
If you scrape off the carbon on a piston you can visibly see the piston part number and then you can find out what you have.
Carbon build up can be from them never really beatin up on the car and only driving short mileage everyday and/or a oil problem.
I would tear down that engine and bring it to a machine shop to check everything over with a mic and plasitgauge. Something is very iffy about that engine.
sorry bro but it happens.Pull of some of the rod caps I bet you will find your problem
06-09-2010, 02:14 PM
#6
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Are the metal shavings steel or aluminum and if so were they on the threads of the head bolts as you were taking them out? Maybe if the shavings were on the bolt threads perhaps the head bolt holes were tapped and not blown out well enough. Or were the shavings inside the motor like as soon as you pulled the valve covers off you saw the shavings on top of the heads or in the valley?
06-09-2010, 02:28 PM
#7
Couldn't see the shavings immediately because they were covered in oil. Not sure if they are steel or aluminum, its more like a powder, if you apply pressure to those masses on the rag they easily flatten out. The third picture up from the bottom kinda shows how I found it, but there was more oil there. When I put the socket on that bolt to take it out it wouldn't go down, I thought great, there is something other than oil there!
Yeah Rob I don't know, I guess every used LT1 in the Tampa Bay area is garbage!! Not sure, it could be old bearing or new bearing, I'll get a better picture of it tomorrow, I think I'll drop the pan then. Its so hot here in FL now, what a pain in the ***.
I had bought the_Merv's old motor, and that thing is still running strong, taking daily beatings! But now this will be the 4th junk LT1 in 2 years that I've had to deal with, its starting to get old!
I suppose I should try to take a magnet to the shavings?
The only back history I have on the rebuild was that the guy was going to go 383, but ran out of funds so they just did the .030 over and went with the JE(still have to confirm what the pistons are). So supposedly it was a shop that put this thing together! Its either a extremely dirty job or put together half assed I guess!
Yeah Rob I don't know, I guess every used LT1 in the Tampa Bay area is garbage!! Not sure, it could be old bearing or new bearing, I'll get a better picture of it tomorrow, I think I'll drop the pan then. Its so hot here in FL now, what a pain in the ***.
I had bought the_Merv's old motor, and that thing is still running strong, taking daily beatings! But now this will be the 4th junk LT1 in 2 years that I've had to deal with, its starting to get old!
I suppose I should try to take a magnet to the shavings?
The only back history I have on the rebuild was that the guy was going to go 383, but ran out of funds so they just did the .030 over and went with the JE(still have to confirm what the pistons are). So supposedly it was a shop that put this thing together! Its either a extremely dirty job or put together half assed I guess!
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06-09-2010, 02:40 PM
#8
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those pistons do not look like no JE piston i seen before.if you scarp some of the carbon off it will have a part# on it just run the number and see what it is
07-05-2010, 12:09 PM
#10
Update: copied and pasted from my post over on fullsizechevy.
So that is the piece of mangled metal that was stuck in the pickup screen.
Here is where I attempted to get a better shot of the solid piece of metal that had been hiding in the oil by the head bolt.
Ran the number, Melling High Volume oil pump. I might be wrong on this, but I think I read on ls1tech that there were some failures with this pump?
That's how chewed up the oil cooler threads are for the oil filter. Really? WTF?! Ah well in the trash it went. I never use those anyway.
Still hard to find an official information source on those pistons, quick search turned up a set for sale on another website, .040 over and forged that ad had said. Going to SRP's website only somewhat helps as their piston isn't labeled the same way as their parts chart is. Kinda wondering so I can figure out what kind of compression I'm going to end up with? I guess I can see why the guy said it had JE pistons in it, JE makes SRP??
So that is the piece of mangled metal that was stuck in the pickup screen.
Here is where I attempted to get a better shot of the solid piece of metal that had been hiding in the oil by the head bolt.
Ran the number, Melling High Volume oil pump. I might be wrong on this, but I think I read on ls1tech that there were some failures with this pump?
That's how chewed up the oil cooler threads are for the oil filter. Really? WTF?! Ah well in the trash it went. I never use those anyway.
Still hard to find an official information source on those pistons, quick search turned up a set for sale on another website, .040 over and forged that ad had said. Going to SRP's website only somewhat helps as their piston isn't labeled the same way as their parts chart is. Kinda wondering so I can figure out what kind of compression I'm going to end up with? I guess I can see why the guy said it had JE pistons in it, JE makes SRP??
07-05-2010, 01:41 PM
#14
the carbon build up like that most of the time is due to oil blow by.
Call kris nelson an have kris rebuild it for you..the thing will be done right and run strong..kris does alot of racing engines and such..He does alot of local peoples stuff and people all over.Im sure you have heard of him.hes great to deal with and when i lived in florida hes who i used for machineing an stuff.
http://nelsoncompetition.com/
Call kris nelson an have kris rebuild it for you..the thing will be done right and run strong..kris does alot of racing engines and such..He does alot of local peoples stuff and people all over.Im sure you have heard of him.hes great to deal with and when i lived in florida hes who i used for machineing an stuff.
http://nelsoncompetition.com/
07-05-2010, 02:45 PM
#15
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That motor has to have over 15-20k miles like that guy told you.. When I pulled my heads off at 15k miles, the pistons looked almost brand new.. Wtf. Hopefully you figure it out. Good luck!
07-06-2010, 06:54 AM
#16
I keep wondering if that squiggly piece is from a valve stem seal. That piece of crushed metal that was in the pick up kind of reminds me of a valve stem seal also.
Yeah, have to get motivated to tear my first short block down, why does this stuff always happen in summer? Its been brutal, 95+ and humid as hell all month.
Yeah, have to get motivated to tear my first short block down, why does this stuff always happen in summer?
Its been brutal, 95+ and humid as hell all month. 
