[hueyhoolihan]

the key here is that things work when at ambient temperature and fail as temps rise. any guess as to the nature of the problem i would think need to address that issue.

anyway, it should be easy enough to test whether or not the fueling is the issue as the carb's float bowl can be tested for the presence or absence of gasoline when the engine refuses to fire. and can be easily filled by hand if necessary. a more convenient method would be to simply spray some very combustible material (ether, brake cleaner, carb cleaner, etc.) into the intake while cranking the engine. if she won't fire at all, it's most likely not a fueling issue.