Hi alfred,
earlier in this thread there was talk about the fuel tank support being too low.
that is true as the centerline of the tank should be inline with the carb.
My o.s. was hard starting and would not idle. I raised the tank level to centerline of tank inline with carb, and
it worked fine.
Was this the case with your engine? does your engine have a pump?
I also had to do a little tuning because i used a pitts style muffler inplace of the stock muffler, first time with this engine.
It runs great now.