Re: Hole in the middle of the Crank...
Can I sneak in my 2cents?
Is it possible this engine has a lot of hours on it and wear to the extreme and the crank is throwing the piston too high causing it to hit the head?
Wore out bearing could do this in an engine that already had a close clearance???
Perhaps a thicker base or head gasket???
DaveC... I just found my old inch/lb snap-on the other day... no clue on it's state of calibration, but it's got a 1/2" drive! lol