Crank question, run it or grind it?

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Siksty7 Dart 270

FABO Gold Member
FABO Gold Member
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I found these 2 imperfections on my Magnum crank. Do I run it as is or take it in for a grind? The worst looking trinagular one is .010" deep. In case you couldnt tell thats the front main journal. I'm doing a re-ring, ball hone, rattle can rebuild, just upgrading to a thinner head gasket, stouter cam and valve spring upgrade.
 
What did the old bearings look like. I'm thinking that will tell you if that imperfection is being picked up in the bearing material.
 
Wish I knew that. I picked up this long block disassembled no bearings present for little money because the cylinders looked excellent.
 
If that's a ding, then there is going to be some displaced metal. Make sure that the edges around it are not raised.
This ^^^^ As long as the edges are not proud, it'll go. You might hit it with emery cloth......and I wouldn't be afraid to even hit it with a small file.
 
YouTube polishing crank journals. It can be done just don't go crazy with it. Measure clearances to make sure it's within spec. Those imperfections need to be carefully dressed to prevent wear on the bearing. Anything you can feel as you drag your fingertips across the boundaries of the triangular shaped damage, will dig into the bearing.
 
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