Hmmmmm

Other than a few rusted valves, the head looks fairly good. No obvious signs of gasket failure, so I’m guessing the head must have warped.

Getting the head off the U-20 was much more of a pain than the R-16. It took hours to get the bolts on the carbs off, the intake and exhaust were also a pain.

The good news is that I have a line on a running U-20, stay tuned.