it has spark.. yet starts and dies and repeatedly pukes fuel out the carb.. yet you are confident the carb is fine.
i'm seeing plenty of evidence that the carb is NOT fine.
if the flaot valve is sticking. you have a float, or needle/seat issue.
floats don't stick on fine carbs. ;)
the spark check is the key. if it has good steady spark .. and you have had it running.. which means it runs and timeing and compression are adequate... then look at fuel.