Honda B75 1972 dies after 2 min when throttle opened

[brotherb75]

I have a B75 that runs great at low rpm, but when given a little fuel revs high, and after a few minutes dies. Primer ball is soft but not empty. Pump primer makes little difference only prolongs for a shorttime. Have ensured that fuel pump is working and taken carb apart looking for obstructions and cracks in gasket.

At full throttle seems like it is getting flooded out, but runs poorly for about 20 seconds

A little past start seem to be the best way to run it but only puts out about 3 hp