Help identify these bearings.

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80BrownK10

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Just double checking this is a 30 under bearing right?
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80BrownK10

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And this is a rod cap. I don't have a clue what any of these mean and google hasn't helped me yet.
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Bextreme04

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And this is a rod cap. I don't have a clue what any of these mean and google hasn't helped me yet.
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Those look like standard size bearings to me. I would hope that the crank wasn't so badly damaged on a previous rebuild that they had to turn it .030" over. Why do you want to know what size the old bearings are? I highly recommend going through proper procedure for measuring the bearing journal size and the crank sizes and then ordering the proper bearings based on the actual measurements if this is a rebuild.
 

80BrownK10

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Here is the same rod bearing. I don't have a micrometer so this is my next best thing. Tried to have the inner measurer on the outer edges and not apply any pressure. From looking up it appears stock journal size is 2.1" so if this is remotely accurate this measures .010 over or undersize I guess you call the bearings?
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80BrownK10

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Those look like standard size bearings to me. I would hope that the crank wasn't so badly damaged on a previous rebuild that they had to turn it .030" over. Why do you want to know what size the old bearings are? I highly recommend going through proper procedure for measuring the bearing journal size and the crank sizes and then ordering the proper bearings based on the actual measurements if this is a rebuild.
That one that's -30 is a main bearing. I should of specified that.

I want to know the size bearings cause I'm doing the shade tree fix of rolling in new bearings and replacing the rods to try to increase my oil pressure.
 

80BrownK10

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This is stamped on the front most crank counter weight.
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Bextreme04

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This is stamped on the front most crank counter weight.
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Well.... that's all you need to know right there. The Crank is what determines the bearing oversize. That means both main and rods need to be .010 oversized. Its the best you can do with what you are trying to do. Getting any more precise than that requires removing the crank and actually measuring true clearances. The problem with doing it this way is that each individual bearing will be slightly different and to really get it right you need to mix and match shells to make sure they are all correct. Its also important to note that often low oil pressure can be from destroyed cam bearings if a PO changed a cam out and mucked them up.
 

80BrownK10

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Well.... that's all you need to know right there. The Crank is what determines the bearing oversize. That means both main and rods need to be .010 oversized. Its the best you can do with what you are trying to do. Getting any more precise than that requires removing the crank and actually measuring true clearances. The problem with doing it this way is that each individual bearing will be slightly different and to really get it right you need to mix and match shells to make sure they are all correct. Its also important to note that often low oil pressure can be from destroyed cam bearings if a PO changed a cam out and mucked them up.
I have heard and read about the bad cam bearings. I'm sure there worn as well. But all these bearings show lots of wear so it won't hurt the oil pressure to swap them out. We will do this and see what I get.
 

80BrownK10

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Well.... that's all you need to know right there. The Crank is what determines the bearing oversize. That means both main and rods need to be .010 oversized. Its the best you can do with what you are trying to do. Getting any more precise than that requires removing the crank and actually measuring true clearances. The problem with doing it this way is that each individual bearing will be slightly different and to really get it right you need to mix and match shells to make sure they are all correct. Its also important to note that often low oil pressure can be from destroyed cam bearings if a PO changed a cam out and mucked them up.
Don't you call it undersize bearings as the crank is ground down so the journal is undersized of std. I guess the oversize bearing size also makes sense as it will be thicker than standard shell.
 

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Don't you call it undersize bearings as the crank is ground down so the journal is undersized of std. I guess the oversize bearing size also makes sense as it will be thicker than standard shell.
Honestly... no idea :happy160:
 

80BrownK10

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Is this going to be an issue. The old rod bearings have a hole on the seam of both half's for some reason, the new ones don't. I don't see why it would matter.
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