I'm going to try to describe this to the best of my ability without having a picture, or a way to measure the grooves. I took my crank over the the machinist who was going to narrow my aftermarket rods. I mentioned earlier that I wanted to verify the stroke against what the crank grinder said it came out at. I didn't really ask him to do it, just said I was interested.



Well, in the midst of all his machining he decided to take my cherry, freshly ground crank, and set the main rods on these two wierd SHARP metal pedals that he had and spin it will measuring the stroke with a dial indicator to check the stroke. When I picked it up he said that the lines made from the spining of the crank on the pedastals would polish out and that I shouldn't be worried about it.



WELL I AM! I'm not a machinist. This is my first engine build. But why would a machinist place my crank on metal, not a bushing, and spin the crank through each stroke leaving a nice little groove in the two outside main rods!?



I can't feel the groove with just my fingertip, but if I gently glide my finger over the grooves I can feel it catch. My guess is that it's a nice little groove about .0005"-.001" of an inch deep!



Should I be worried? It's a 312 that's just barely been ground down to 292 mains. I would really, really, really not like to grind another .010" off the mains just to clean up the guys mistake.



But I don't want to have a nice oil dam, or uneven oiling of an engine that I'm rebuilding! What should I do? I can take some pics tonight and post them so you guys have a better idea, but right now I'm clueless as to what the groove would do if left unchecked, and frustrated at the prospect of redoing work that is costly. Thanks, Ryan

Heber City, UT (15 mins outside of Park City- basically it's in the mountains)

55 Effie