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400 crankshaft problem?

ctyesterday

5
0
I am rebuilding the 351m that was in my 79 ford f100. I decided to turn it into a 400. I ordered a crankshaft from northern auto parts that is thirty under with bearings to match. When I plastigauged the mains I found that my clearances were between .002 and .003. Everywhere I look it says my clearances should be between .0008 and .0015. As far as I know the only problem would be they messed up on turning the crank. Could there be another issue?
 
SuperCab

SuperCab

Moderator
Staff member
10,068
547
Montana
The bearings should be marked .030... Are they? Had kits come with the wrong bearings before.

Other than that, mic the crank and see would be my only suggestion.
 

ctyesterday

5
0
The bearings are marked 30. I figured the only problem could be they sent a bad crank but you think they would check it before they sent it out since they say they recondition the cranks. Also with the original 351m crankshaft my clearances were about the sameas the 400.
 

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