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Discussion Starter #1
I have problem with crankcase upper and lower its not from the same engine ,anybody ever put one color of main bearing in upper and another in lower crankcase (exempl up yelow down green) for have corect clearence ,its this works ?????
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Sorry to say but this is almost certainly not going to work. It's not about just diameter but also centre line. You might be VERY lucky in that both cases might have the same centre line, but you need to check this meticulously, and then you have the PIA of organising 2 sets of bearings. Which are sold in pairs of course. A possible solution would be to measure how much offset you have and then correct it by machining new dowel holes but oversize (a couple of thou). Obviously a job for a competent machine shop, but cheaper than a new block. I learnt this the hard way when trying to use camshaft holders from another cylinder head. It ran fine for 5 minutes, long enough for me to get a mile down the road before the inlet cam seized and wrecked the entire head.
 

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True they don't but they have tight clearances just like the crankshaft. You won't see the lateral offset with plastigage. That's why crankcase halves are line bored (together) as matching pairs, to ensure there is no offset. I'm not saying don't do what you are thinking about, just make sure you not going to waste a lot of time and expense.
 

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Discussion Starter #5
True they don't but they have tight clearances just like the crankshaft. You won't see the lateral offset with plastigage. That's why crankcase halves are line bored (together) as matching pairs, to ensure there is no offset. I'm not saying don't do what you are thinking about, just make sure you not going to waste a lot of time and expense.
 
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