if you think it is the carb take that sucker off, blow it out good with an air hose and see what happens, might even use a spare carb if you have one, you might also check to see if there is any where in the gas line that has a small hole or crack in it, that might be causing a burp. I know , one would think if there was a hole in the gas line you could find see it or smell it real quick... not always..
is it possible that it is not a fuel problem but a break down in
the coil or else where when it gets hot it is hard to start back up..