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Discussion Starter #1
I was installing new main bearings today .25mm oversize and I could not get the crank to rotate freely. I double and triple checked the main cap positions and orintations. I mic'd the crank, installed the bearings without the crank and mic'd the bore...all seems good. Any suggestions?:idea:
 

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Did you check your clearance clean and dry using "Plasti-gage" :idea:
 

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Well so much for relying on my digital micrometer....Per Bob S. suggestion, I checked the clearance with Plasti-gage. The result is I have clearances from .001" to .002" and it's back to the machine shop to turn the crank a little. Thanks Bob S.
 

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What clearance does Cummins call for ?

i usualy do one cap at a time and rotate the crank once to see if anything is out of wack . I once had a thrust bearing that would sit high . It turned out the block had not had a radius machined at the favctory . We radiused the block with a grinder and were good to go . Hard to explain but it worked like a charm .

Bruce.
 
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