Hello all!
I have a vintage McCoy .19 Red-Head C/L engine which I was disassembling to clean and overhaul. Unfortunately, when I was removing the screws which anchor the red head to the crankcase, one crew broke, leaving maybe 3 mm or so of steel # 4-40 screw stuck in the aluminum crankcase. Do you think it's possible to drill and tap this fragment out, and still keep it in 4-40 size? Or, should I drill it out and go up in size to a #6-32? Or, is the entire crankcase now junk? Any thoughts? Thanks!
C.R.