Why did I spin a main bearing?

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zinser72 said:
I had .002 clearance plastigauged on all mains and crank was polished. Engine ran great for 3500 miles and with no warning at all I lost oil pressure and it died immediately. Nothing wrong with oil pump, drive shaft, cam gear or timing chain. running amsoil z-rod 10w 30 @ 60psi when its warmed up at idle. What did I do wrong?
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Check your oil pump driveshaft closely--I have seen the hex part round off and just spin in the oil pump. Is it possible that your drive gear on the shaft is not pinned and spun--That would cause the distributor to stop turning causing the car to die immediately and zero oil pressure simultaneously. If it isn't that then you need to elaborate and describe carefully what happened. Ex---You say you lLOST oil pressure--What does that mean? Zero--10lbs--15lbs---Less than 60psi? Just trying to pin point for ya. J.Rob
 
did you youse your old oil pump?? is the pick up tube cracked sucking air you clearence is a little tight but i dont think that was the problem know im not being a smart *** but i see your bearings are in the wrong way i mean your main bearings the ones with the hole should be in the block .
 
zinser72 said:
yeah its a 4 speed, when i got it home i checked everything with the cam, valve springs, lifters and oil pump i primed it and everything looked good. so i made the mistake of trying to start it again. oddly enough the starter cranked it fine but its a high torque mini starter, only thing that clears my headers. when it fired it took about half throttle to hold it at 400-500 rpm so i shut her down right away.
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So when you primed it--What did the guage show? You are not providing enough info. I will say that if you needed half throttle to keep it running--You are looking at something major. J.Rob
 
yes the chunk somehow made it through the pickup screen and through pump, #3 main is not missing a chunk, just looks wierd in pic i see what you mean though. hex is fine on oil shaft and gear did not slip. dont know what the oil pressure did, no gauge in car just the idiot light, sorry
 
did you look at the pics the main bearings 1-2-and 4 are in wrong thats why he has the problems he does .?
 
robert 68 cuda said:
did you youse your old oil pump?? is the pick up tube cracked sucking air you clearence is a little tight but i dont think that was the problem know im not being a smart *** but i see your bearings are in the wrong way i mean your main bearings the ones with the hole should be in the block .
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new pump, pickup tube look good and as for the bearings, in the kit i got both halves have a hole in the middle for some reason but the holes are lined up with the oil galley on other side
 
Plenty of main bearing sets come with holes in both the upper halves and lower halves. He has the correct bearing shell in the the number 3 and 5 --Besides if they really were all wrong you would be seeing copper on those ones.--OP pull some rod caps and check those. J.Rob
 
I'm sure you know this already, but just a reminder to keep those caps in order if the're not marked.

Sorry, i reread where you marked them before.
 
well then thats one more thing off the list then does your cam bearing oil holes all line up ??? this doesnt make much sence may be your oil pump failed the weared part is this most mopars like flow them pressure what kind of oil pump did you get.??
 
not sure, think its a high volume though. I know that's a mistake for the build i did but thats what the guy ordered for it when we built the engine
 
In your other thread you described the noise as a squeal or screech. That's a tell tale sign of a bearing noise?

I'm afraid your looking at a complete freshen of this engine:sad7:

And adding the oil mods that J.Rob talked about wouldn't hurt.
 
OldmanRick said:
In your other thread you described the noise as a squeal or screech. That's a tell tale sign of a bearing noise?

I'm afraid your looking at a complete freshen of this engine:sad7:
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that's pretty much what im thinking right now. im taking it all apart and I gotta wait til i have the cash to do everything right. everything will be checked at the local machine shop. no corners cut this time. oversize pistons and all. im just lookin around for stuff to sell at this point haha
 
i was just really hoping it would be an easy fix but it just looks like a everything is wrong so i guess im gonna give up on finding the single cause of my issue. kinda sucks though. took me 5 years to get this far and now it time to take a break
 
zinser72 said:
that's pretty much what im thinking right now. im taking it all apart and I gotta wait til i have the cash to do everything right. everything will be checked at the local machine shop. no corners cut this time. oversize pistons and all. im just lookin around for stuff to sell at this point haha
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Sorry for your trouble, none of us need these kind of issues right now.

Good luck and hope everything works out ok for ya' Rick
 
Not sure if it's my monitor, but it sure looks like a bunch of junk was ran through those bearings.

Did you pull all the plugs and clean all galleys and passages?
 
What does the cam look like? Are the lobes and lifters wiped? I don,t see how a piece that size would make it through the screen in pick up. Looks like trash that was in oil passage somewhere. I would also look at oil pump shaft as it may have broke off. Before you put it back together I would knock out the oil plugs and get long bottle brush and scrub block real good with soap and water. Blow it dry with air the spray it with rust inhibitor.
 
I have been watching and reading this thread. After looking at the pictures several times and reading the posts several times I am thinking along these lines.

1. I can't see how that peice of metal got past the screen on the pick up tube.
2. Oil Pump clearly has damage.
3. Metal was in the oil filter.
4. No obvious damage to the mains and crank bearings.
5. Squeals and noise with loss of oil pressure.
6. Engine died when this happened.

With all this I have to wonder if there was a peice of metal that stayed in the oil pump when it was manufactured or maybe there was a peice of metal inside the pick up tube? The damage to the oil pump would account for the noise and it binding up from the peice of metal could kill the car. Now guys correct my reasoning here if I am off base.
 
I would think the pump drive would shear pretty easy if there was junk stopping it, I have seen them sheer off in motors with 20W50 people had to start below zero.
 
dodgetkboy78 said:
I would think the pump drive would shear pretty easy if there was junk stopping it, I have seen them sheer off in motors with 20W50 people had to start below zero.
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This wasn't a cold start motor, it was running when this happened. The peice could have been just large enough to make the noise, still pass through the pump but had enough drag to stop the engine. Obviously the engine started again and the metal may have been crushed enough to still be in the pump and exited later. I am thinking with logic and logic sometimes flat won't work in real life.
 
Oklacarcollecto said:
I have been watching and reading this thread. After looking at the pictures several times and reading the posts several times I am thinking along these lines.

1. I can't see how that peice of metal got past the screen on the pick up tube.
2. Oil Pump clearly has damage.
3. Metal was in the oil filter.
4. No obvious damage to the mains and crank bearings.
5. Squeals and noise with loss of oil pressure.
6. Engine died when this happened.

With all this I have to wonder if there was a peice of metal that stayed in the oil pump when it was manufactured or maybe there was a peice of metal inside the pick up tube? The damage to the oil pump would account for the noise and it binding up from the peice of metal could kill the car. Now guys correct my reasoning here if I am off base.
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Sounds reasonable to me. Only thing i could find a argument for would be if it was bound enough to stop the engine wouldn't it have sheared something in the process.....idk?

Hope he doesn't feel to bad about this, years ago i did a berrybush, rings and new bearing rebuild on a SBC and broke a piston ring about the same mileage as him. Took a chance and got about 3k miles out of it....oh well:)
 
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