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Discussion Starter #1
I know very little about bearings, but they are not supposed to look like this right? All the rod bearings look like this:





 

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Discussion Starter #4
No clue. Bought it a few years ago off craigslist. I'm going to take the block, crank and cam to the machinist so they can tell me whats up.
 

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Everywhere the copper is visible, the babbitt has been worn away.

If copper shows AT ALL, the bearings are worn out.
 

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looks like the crank lobe aint flat from side to side and the rods aint good and evenly round.
 

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Discussion Starter #7
I guess its a good thing I didn't just plop the engine in and run it as-is then eh? I was hoping to get away with just needing new bearings, but I know its never that easy. Wish me luck.
 

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Rods are more likely needing rebuilding gauging from the uneven wear. Its one of those things where you might be able to throw bearings in it, scuff the cylinders, replace the rings and it last a few years to 10 just fine. As long as you don't mind pulling the engine if it doesn't work, not much to loose. Definitely check the lower timing gear on the crank and if its any kind of plastic, replace it. Otherwise stock motors tend to just go till you get sick of putting oil in them "usually". I bought a 302 out of a high mileage car so I could drive while I rebuilt my motor. It actually had great compression and oil pressure and ran fine but that damn timing gear let loose with some pretty dramatic pyrotechnics.

Good luck,

M
 

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Discussion Starter #9
Here is the full story, I'll keep it short: I bought the motor for another car, got new stock sized pistons and rings, slapped it together and it sat, I never ran it. A year later I remembered the bearings looking sketchy, so I tore it back down which is where I am at today.

When I mic'd the cylinder bores, they were within stock specs, I could not feel or measure a lip, and they still showed x-hatching. I HOPE I can get away with some machine work to the lower end, and be able to use my new pistons and rings that I already have with a light hone. The rods were put on the pistons by a machine shop a year or so ago, he said he also rounded out the crank ends on them.
 

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If you are going to do the crank then have the rods straightened. If they did not "rebuild the rods" and only worked the "big end" your problem is not gone. Its not a big end roundness thing and usually quite frankly the machine shops make the big end less round by machining the rod caps so that the major load bearing surfaces are in spec. That aside, if you are going to do the crank, have the rods straightened otherwise toss bearings in it and see how long it lasts - probably quite a while if its stock...

M
 

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Here is the full story, I'll keep it short: I bought the motor for another car, got new stock sized pistons and rings, slapped it together and it sat, I never ran it. A year later I remembered the bearings looking sketchy, so I tore it back down which is where I am at today.

When I mic'd the cylinder bores, they were within stock specs, I could not feel or measure a lip, and they still showed x-hatching. I HOPE I can get away with some machine work to the lower end, and be able to use my new pistons and rings that I already have with a light hone. The rods were put on the pistons by a machine shop a year or so ago, he said he also rounded out the crank ends on them.
I'm confused...the machinist resized the rods, and you slapped it together with used bearings???
Anyway, if the crank is ok, get it polished and throw in a new set of bearings.
 

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Discussion Starter #12
I'm confused...the machinist resized the rods, and you slapped it together with used bearings???
Anyway, if the crank is ok, get it polished and throw in a new set of bearings.
I'm not sure if he re-sized them or not, he was a strange old man and the only thing I remember was him saying he did work to the big ends, maybe he said he "cleaned them up" or something. I never ran it like that, and after two years of experience I figured I better tear it apart and do it right, which brings me to where I am today :)

Bearings scare me though, the tolerances anyway.
 

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Hi,

Hopefully, you'll find a modern machine shop who will check it all. Perhaps, show them a few of the wear characteristics of the bearings. Do, have new cam bearings installed, but, then a reputable shop will advise that, if found necessary.

Good Luck!
 

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yep you see cooper and on the caps you see lighter metal time for a rebuild. those bad things to see well if you dont want to rebuild it that is.
 
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