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After this thread http://stevesnovasite.com/forums/showthread.php?t=36159 I got out the dial indicator.

With center cap installed and measuring front journal I got on the small side of .001 maybe .0009 of run out.. Same on rear journal

With front and rear cap installed and center 3 out i measured the runout of center journal. it was nearly perfect. The .0001 needle barely moved.

Is there another way to check or is this correct.
If it is correct I think the crank is A ok.
Now to mic the journals.
 

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The crank doesn't sound bad (run-out wise) Pro. The trouble is that when you tightened the center cap, you MAY be just straightening OUT the crank so to speak. Same with installing the end caps after. The "ideal" way to check for run-out is between centers (like in a lathe set-up) or on specially designed roller set-up supporting the journal areas, but your method will probably do.

When you mic the main and con rod journals, check them in several different planes looking for any "egg" shape as well.

Now the HARD part is checking the block's main bearing BORES. The way to do that is by installing an alignment BAR, and using a dial indicator set-up, sweep the machined surfaces. A bit of a challenge even with the right equipment. You could get a reputable local engine builder to do that I suppose. ;)

In my experience, the block alignment is found to be more at fault than the trueness of the cranks.
 

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I pull the bearings out of the block except for the front and rear. I install a indicator on the center main of the crank and turn it over. You would like zero runout. I only check when the bearings show problems or someone brings something to me I know nothing about. I just had a crank last fall that seemed to have 002.5 runout in it. Took it to the crankshaft man and it actually was 004 out from #1 to #2 so 2,3,4 and the rear were all straight and the front end was wobbling. That's how I do it. RM
 
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