Got a junkyard motor to put in my 97. It's a 4.2 from an 07. I've got it all torn down to move necessary upper parts from the old to the new, and re-gasket everything but the heads.

So that's the back story. Now to my problem. At the exact same spot in every 1 turn of the crank, there is a stop that's takes considerable force to work through. It happens at the exact same spot in every turn, so it's something that occurs at a 1:1 ratio with the crank. Would bad main bearings cause something like this?