RE: us41 in byron p51
I had one of these engines a few years ago and although it ran GREAT, the only way I was ever able to hand start it was to slap the prop as hard as I could. I dont recommend that, by the way. I started using a starter. If you got it running it more than likely is still getting fuel. Fix the throttle linkage and try it again with an electric starter. Until you have a reliable starting METHOD you will be chasing your tail. Hope you get it figured out.
Brian