Look at the red circle. Is it me, or does that look like the head of a fishing jig?
Pieces of steel in cylinder??
- Thread starter Righty Tighty
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I get a chuckle out of people going down the Sabotage path.
Can look up melted bearings on google and see stuff like that. Surprising that the crankshaft did not get the bearing alloy transfered on to it, was expecting to see that. Guess he shut it down just in time before the crank went down.
Can look up melted bearings on google and see stuff like that. Surprising that the crankshaft did not get the bearing alloy transfered on to it, was expecting to see that. Guess he shut it down just in time before the crank went down.
I laugh at myself too cause that's all I can do.
Cuda416
Well-Known Member
You might be right, but I find it telling that no one so far has been able to say ...
"This is what happened and this is how, because I've seen this exact thing under these conditions...."
It could still be a product of some chemical reaction. either some additive poured in by mistake, on purpose or by someone who really knew what they were doing. At this point, no one knows for sure.
I'm the first to agree that I've only seen a few spun bearings but it seems to be there would be much more scoring if there was enough heat to melt (or soften) a bearing to that point. No? I dunno...
Could it be innocent? Sure, of course. The other options are still on the table until there is a definitive answer. The easy way to see what that metal is, is to melt it down and observe it closely. See how it behaves and when it melts. If it melts below 200C, it's likely an alloy that's meant to melt at low temps..
I do find this all extremely interesting...
All the spun bearings I've ever seen turn to tin foil like in one of the pictures above. Course I ain't seen everything by a country mile, so that means nothin. lol
nm9stheham
Well-Known Member
LOL... but dang I think you are onto something. And look to the right of where you put that red circle....is that a eyelet of brass? New theory: someone was 'fishing' in this engine for a dropped bolt or sumpthin', and lost the hook and sinker.
LOL... but dang I think you are onto something. And look to the right of where you put that red circle....is that a eyelet of brass? New theory: someone was 'fishing' in this engine for a dropped bolt or sumpthin', and lost the hook and sinker.
I saw that too......but decided I was too lazy for more than one circle. Is that bad?
nm9stheham
Well-Known Member
Yes being lazy is bad... which means I must be awful LOL. I should be replacing a tailpipe right now....
It could also have been stupidity/incompetence by the builder...
I have an unfair advantage cause I blew up that photo of the bearing slag on the computer screen, confirmed no fishing tackle.
Lol . . Good Times . .
Thanks
When the seat disintegrated and then the piston hit the valve insert material, then the oil that is used for the boundary layer lubrication can get squeezed out and then the bearings go metal on metal and the bearing material will shear/smear...
Great Explanation, oil for boundry layer got squeezed out from the extream high pressure of the piston bottoming out against the seat material sending the presure down to the crank bearings.
The bearings are the weak link in the rotating assembly to hammer out first and protect that important crank shaft when things go bad.
The Bearings did their job, protecting critical machine work around them.
Incorect...
What you are seeing it the witness mark from the oil feed hole that is drilled through the main to feed the lifter galley... That hole is not centered, but offest slightly and you are seeing that...
Notice how the holes for the oil feed holes for the lifter galley are offset toward the passenger side of the block here... You can tell it's the passenger side because that's the same side as the oil filter mounting...
Here I have circled the marks on the back of the bearings for those holes, I bet if he turned the bearing over, they would be on the opposite side of the anchor slot/tang...
I have highlighted the oil feed holes in the block here, as you can see, they are slightly offset and there is block material all the way up to the hole, where the center hold that feeds the cam bearings is counter sunk...
These witness marks that I have highlighted in blue are the halo from the counter sunk cam bearing feed passages...
Here are the cam bearing feed passages to show where those marks came from...
The material in the holes here is the bearing material that was sheared/smeared when the boundary layer lubrication was lost and the bearing took the brunt of the force like it's supposed to... When the material was smeared and moved, it had to go somewhere, so it filled the holes... The bearings are made to be softer than the crank journals so they take the brunt of the damage to help minimize what the crank sees... This helps save the crank from damage when these things occur...
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Come on yall. We're all supposed to be like family here. That doesn't mean we always agree, but we don't have to be nasty. The engine had a failure. He's fixin it.
MOPAROFFICIAL
If it has tits, it's a liability.
The old bearings would smear, tri metals dont and that's what most of us have and used for the last 20 yrs...so this visual isnt something a lot of our eyes are used to.
Maybe even for some..it ticks them off to see such neglectfulness of either maintenance, assembly, or even the thought of sabotage.
Get it fixed.
Maybe even for some..it ticks them off to see such neglectfulness of either maintenance, assembly, or even the thought of sabotage.
Get it fixed.
The bearings will also heat up when the boundary layer lubrication is lost because there is no oil to keep them cool...
This thread is closed until it can be cleaned up.
Exactly.
I'm thinkin' some of this made it into the oil causing the bearing issues. Like someone mentioned.
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MOPAROFFICIAL
If it has tits, it's a liability.
Early small blocks like my 1970 340 do not have the counter bore around the oil feeds therfore cause oil starvation in even moderately high rpms.
Ontop of being too small the bearings oil holes also sit offset toward the intersection of the cam oil feeds... which is right above the restrictive small v shaped opening where the 2 intersect...you starve the motor that way. Pretty easy to put together I would think.
Shadow, witness mark... terminology differs, you reword what I say with your typical smugness and intent on correcting someone... and you still miss my point.
Sad.
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The ambassador of good will? What is the world coming to!
BHAHAHAHAHAHA!
MOPAROFFICIAL
If it has tits, it's a liability.
2 cent theory: looking at the piston there was no major damage to the piston top. More like shot peening going on inside the combustion chamber. A steady hammering would have resulted in damage to the rod journal of the crank. My guess is that the main bearing ran out of oil, allowing the soft bearing material to heat up to the point of becoming a semi-solid, which plugged up the oil feed hole from the block, which starved the feed hole in the crank going to the rod bearing. And actual melting of the bearing took place at some time. Note that this wouldn't happen with the old Mopar bearings which are mostly soft steel with a coating of copper and then a thin coating of a soft gray alloy material that rides against the crank.
To be honest, you're sitting on a pile of junk. A .040 over block that needs reboring and oil passageway complete cleaning, a set of heads that dropped one valve seat already, a crank that is .040 under, and other possible unknown problems. I'd buy a 1973 or later 318 from a car or pickup truck with a carb. Then change the timing chain, and run it. While your engine has been a great educational tool, it might end up being a money pit.
To be honest, you're sitting on a pile of junk. A .040 over block that needs reboring and oil passageway complete cleaning, a set of heads that dropped one valve seat already, a crank that is .040 under, and other possible unknown problems. I'd buy a 1973 or later 318 from a car or pickup truck with a carb. Then change the timing chain, and run it. While your engine has been a great educational tool, it might end up being a money pit.
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