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Anyone care to read the "tea leaves" here ,The BBC Clevite rod brg inserts are from a jet boat motor with about 5 hrs on it , as seen they all have similar characteristics but some to a greater degree. The Crank is a new Scat unit and still looks perfect , rods were resized, its obvious that some "junk" has passed thru them from a diffferent issue (circumferal scores and partical embedment) but the "dotted" spotty patterns that are pervasive to some degree in all are curious. We know what we think , anyone else Thanks in advance Merry Christmas everyone Tom


 

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Check measurements on that crank..I'd like to see pics of it also...what in the hell went thru that motor?? some of the bearings appear to be darkened? or is it just the pics...what was oil pressure on that motor. also...what are the clearances on the bearings to crank??
 

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The residual oil in the pan was a little dark and smelled of fuel a "smidge" and it had some "cold block" condensation in the upper engine but no "milkshake" (that we know of ;) ) Tom
My vote was going to be foreign liquid in the oil:)st,,
also the cold oil temp wont burn off the contaminate's..... ( just my opinion:(:( )...Eric:)hand

ps : Have a Merry Christmas
 

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Discussion Starter #7
Check measurements on that crank..I'd like to see pics of it also...what in the hell went thru that motor?? some of the bearings appear to be darkened? or is it just the pics...what was oil pressure on that motor. also...what are the clearances on the bearings to crank??
The motor lost a cam (the "junk"), Cold OP was 70 psi , Crank looked perfect and rd clearance was .002 They may appear darkend due to the photo ? Tom
 

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The crank not cleaned before being assembled..........What do the main bearings look like?
Mike I would agree with you (re the emmbeded particals ) but the raised spots are perplexing , i'm leaning to the moisture too (Mains are similar btw)
 

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What weight oil were you running? When this engine was buiit, did it sit for a long time before it was run? This almost looks like the assembly lube dried up before it ran, or was crap to begin with, or just a dirty build to start with. I don't think what we see is water damage.
Did you build this engine?
Why the guessing game...what do you think? (my bet is you KNOW what it is)
 

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What kind of brake in oil did they use? And did they change it after brake in ? Hope they used the proper assembly lube, And not lube with graphite.
What ever it is If you find out Tom let us know.

Merry Christmas Tom, Rhonda, And josh.
Steve and Janet

All the grate minds took all the good answers.
 

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Tom. looks like a dirty assembly and high viscosity oil with a tight clearance tossed in for good measure. I'm sure you've seen an oil washed bearing before. Again the key here is dirty and tight. The tight is what is rolling the babbit of the bearing, the dirt is whats putting the racing grooves in the bearing.
 

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I'm going to throw my ..02c into the ring...

It looks like you have an oil wash problem, caused by too much cold oil flow, sometimes by fuel diluted oil and have seen it on alcohol engines also..

I would also concur on the debris, but that looks secondary to me...

These look as though it was run hard or overreved on very cold oil with too much oil pressure...

GT :)hand
 

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Anyone care to read the "tea leaves" here ,The BBC Clevite rod brg inserts are from a jet boat motor with about 5 hrs on it , as seen they all have similar characteristics but some to a greater degree. The Crank is a new Scat unit and still looks perfect , rods were resized, its obvious that some "junk" has passed thru them from a diffferent issue (circumferal scores and partical embedment) but the "dotted" spotty patterns that are pervasive to some degree in all are curious. We know what we think , anyone else Thanks in advance Merry Christmas everyone Tom


water flashing off...real hot oil and water.
 

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Discussion Starter #15
How do the lifters look? Can I get a pic of a couple of those?
I'll post them tommorw !

What weight oil were you running? When this engine was buiit, did it sit for a long time before it was run? This almost looks like the assembly lube dried up before it ran, or was crap to begin with, or just a dirty build to start with. I don't think what we see is water damage.
Did you build this engine?
Why the guessing game...what do you think? (my bet is you KNOW what it is)
Scott ,I appreciate someone like you folks (whom i respect) to chime in
Tom. looks like a dirty assembly and high viscosity oil with a tight clearance tossed in for good measure. I'm sure you've seen an oil washed bearing before. Again the key here is dirty and tight. The tight is what is rolling the babbit of the bearing, the dirt is whats putting the racing grooves in the bearing.
I belive dirty assy is part of the equasion

I'm going to throw my ..02c into the ring...

It looks like you have an oil wash problem, caused by too much cold oil flow, sometimes by fuel diluted oil and have seen it on alcohol engines also..

I would also concurr on the debris, but that looks secondary to me...

These look as though it was run hard or overreved on very cold oil with too much oil pressure...

GT :)hand
Glen your my Bud but this made my head hurt I gotta think about it :)!

water flashing off...real hot oil and water.
Mike this is a good thought Thanks Tom

Merry Christmas Everyone Back tommorow with more Pics Tom

PS To the Steve Best Family Merry Christmas to You and Janet !!
 

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Well a coupe do look dark, as is hot hot once. Did it have a remote filter? If so wrong bypass valve? oil filter lines azz backwards?
Had some shiney oil I bet
 

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i dont know if this can happen, but GTJets makes a good point...hot oil and gas flashing. It really looks like acid run thru that thing, or the motor sat for a LONG time with contaminated oil. Salt or fresh water?
 

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Heavy viscosity oil at too high a pressure and cold = tight tolerances with too much oil film thickness...It's wierd, but with only 5 hours of runtime, it was all I had. :)

On my old Renegade, we used the oil cooler to "heat" the oil more than cool it...Did the same thing on the rock boat, it was plumbed to use warm water to keep the oil temps "under control", not just cool...:)bulb

GT :)hand
 

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The more I have this rattling around in my head with the five remaining firing brain cells...:)coffee

I am beginning to lead towards a major cavitation problem within the oiling system...

Have you inspected the oil pump and pick up for issues?

Foamy oil will do weird sh!t too..:)bulb

GT :)hand
 

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Looks like water in the oil to me. Been there done that same effect to bearings. But I'm sure there is more than 1 cause for that.
 
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