Here's my thread about finding a crack in a 37 block in a dumb place after the block was magnafluxed and cleaned and declared good. Not fatal in this case but still would have been a pain if found after installing it in the car.
https://www.fordbarn.com/forum/showp...10&postcount=1
I'm starting on a 36 block that has been magnafluxed and want to pressure test it before I go any farther. How do you guys plug the core plug holes in the pan rail to withstand pressure testing without leaking?