Engine Build Question

rd said:

I am assembling an engine. I plastigaged the mains, and had .0015 to .002 clearance.

After assembling it with the crank, it did not turn freely, so I had the main bearing bores honed.

Since they are slightly larger, ( less than .0005 in larger) can I install the inserts that I have already installed, or have I overcrushed them?

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When you're in doubt, it's a good idea to replace that part that you're not sure you can re-use.

If you still want to persue the idea of re-using them, I would run this question by your machinist.

I hate to tell you, but I think you messed up big time. The clearances you are supposed to have are .0005 to .0015 on the main bearings. Your first measurements were right where they should've been.... but now you had them honed out and that was a bad idea. You should've left them as they were and checked for some other reason the crank didn't spin freely... or maybe you just though it was too tight not realizing that "tight" is normal on a fresh engine.