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steelcomp was here
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Discussion Starter #4
Notice anything peculiar besides the trashed bearings?:)bulb
 

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steelcomp was here
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Discussion Starter #6
System 1 filter ???????????
Ha ha...close. Open bypass port was one thing found, but not the cause. There was no filtered oil going through the engine.
 

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Is the crank worth saving- if so how does it look?

Did a mega unobtanium crank demolish itself to save the inexpensive bearings?

Bores dont look trashed.

Cam looks like it might have worn down a lobe.


Uncle Dave
 

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Scott, are you saying this thing had ample oil pressure but no filtering caused this damage? Either a long time running the same oil, high horsepower application (which I expect given the camshaft type and profile) or something introduced into the crankcase oil that sped up the process of destruction. Can we assume the rods were as bad or worse?
Did something finally fail or did he shut it down when the engine noise surpasses the header noise?
 

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steelcomp was here
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Discussion Starter #12
Scott, are you saying this thing had ample oil pressure but no filtering caused this damage? Either a long time running the same oil, high horsepower application (which I expect given the camshaft type and profile) or something introduced into the crankcase oil that sped up the process of destruction. Can we assume the rods were as bad or worse?
Did something finally fail or did he shut it down when the engine noise surpasses the header noise?
Well since this was brought to me pretty much in this condition, it's all supposition. The crank is toast. The rod bearings aren't quite as bad but trashed, none the less.
This is a blown jet boat deal, and after seeing the curling of the main bearings, my only conclusion is detonation...big time. The detonation curled the bearings which them wiped the crank of any oil causing the bearing failure. At the same time, the cam gear was taking out the front of the block, which added more material to the mix. In the end, I found that the little phenolic valve in the filter adapter bypass was gone. The oil path was straight from the pump, across the top of the filter, right back into the engine. All that foreign material just circulated, taking things to their current state.
It's savable, but we're starting from scratch. The cyl's look good...the rings are trashed. The cam is OK, but needs a polishing. All in all, the damage is limited to the rings, bearings and crank, which has been replaced.
At least that's my take on it.
 

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Ding ding! We have a winner!:)sphss
If they are loose enough to see that in a pic, why are they that loose. and please try to explain it without use the term DETONATION! Wags just could deal with that right now.:D


EDIT: I was writing this as Steel was posting. I pretty much knew what caused it. Just wanted him to explain it with out saying what caused! That is some serious ass detonation right there. He is lucky he still has a block!



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steelcomp was here
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Discussion Starter #14
Is the crank worth saving- if so how does it look?

Did a mega unobtanium crank demolish itself to save the inexpensive bearings?

Bores dont look trashed.

Cam looks like it might have worn down a lobe.


Uncle Dave
It was a stock GM forged unit, which did indeed sacrafice itself to the cause. :mad:

One little detail I left out...the block had been bored and honed and align honed before...and it was obvious that many of the factory galley plugs had never been removed.:)bulb
 

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steelcomp was here
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Discussion Starter #15
If they are loose enough to see that in a pic, why are they that loose. and please try to explain it without use the term DETONATION! Wags just could deal with that right now.:D
Well detonation (or just severe pounding from excessive power...not in this case, though) is the only thing I know of that will do that to a main bearing. Now why it was detonating, I don't know...I wasn't there, but I have a feeling it was a combination of timing by ear and about 12lbs of boost. I also don't know what the original clearances were, but my guess is there wasn't much room for any "trouble", if ya know what I mean.
 

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my only conclusion is detonation...big time. The detonation curled
At least that's my take on it.
AAAAH Bullshit!Lies:)l):ameRealityhil:)hil:)hil:)

Stock gallery plugs never removed. Nice. Unfiltered trash, which leads, to more unfiltered trash, and so on and so on.

I don't know how these people find you steel, but you do seem to get some of the shittiest built motors thru your place.:)sphss



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Hope you folks are sitting down. I not think this was detonation.:))eek:)) I know. I can't believe I am saying that either:D

I think the bearings are just acting like bi metallic springs, except they aren't springs. I check this out last nite on a old bearing. I think they just were heat cycled, more than a couple of time, and were pretty damn hot. Not hot enought to discolor the crank, but I'll bet the bearings aren't al that prestine on the back side. Being bi metallic, everytime they cooled down, the metal shrink at different rates and amount, and caused the curl. Somewhat like a bi metallic spring in a choke thermostat.
They most likely got this hot from lack of an decent oil wedge once the bearing was worn, and damaged.

No matter, this thing is a mess. And Steel gets some doosies:)sphss



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Ive never taken anything apart that had the size gap between the bearing and the saddle/seat, but then again Ive also never seen anything that beat up before.

I take it this isnt normal at all no matter the age or condition.

I lost an oil pump pickup once and idled home pulled the engine and checked the bearings out and they all sat perfectly flat and the bearing was uniform in color so I bolted it all up and it was fine for another 200 hours (except I killed the valve guides and didn't know it.)

sounds like it was caused by beating a dead horse to long. Im surprised the bearings didnt spin around in the seats.

Thanks for the picts- fun stuff.

UD
 

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steelcomp was here
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Discussion Starter #20
Ive never taken anything apart that had the size gap between the bearing and the saddle/seat, but then again Ive also never seen anything that beat up before.

I take it this isnt normal at all no matter the age or condition.

I lost an oil pump pickup once and idled home pulled the engine and checked the bearings out and they all sat perfectly flat and the bearing was uniform in color so I bolted it all up and it was fine for another 200 hours (except I killed the valve guides and didn't know it.)

sounds like it was caused by beating a dead horse to long. Im surprised the bearings didnt spin around in the seats.

Thanks for the picts- fun stuff.

UD
I think you raise an interesting point that the bearings didn't spin, because it was a perfect candidate for it, but that addresses the heat issue. It never got hot enough for a bearing to "grab". There's really no sign of heat in the bearings, but that's not to say they didn't get hot.
There's a lot of contradicting damage here, or at least conflicting, to get a logical answer as to what might have happened. Needless to say, everything will be inspected and checked before it goes back together.
I just though this might make for some interesting discussion and stay friendly. ;)
 
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