[midniteblues]

sometimes you gotta prime the pump/line when its been drained.
try dumping a cap full of fuel into the carb and turn it over.
get it to fire up for a few seconds that should be enough to pull the fuel up the line and too the pump.

a fuel pump is only pumping as fast as the engine turns when cranking.when the line isnt full of fuel the slow spinning pump has a hard time "pulling the fuel".
abit more rpms(from the cap full of gas) should pull the fuel up the line.

check filter in the carb
and blow those lines out
make sure your not collapseing the rubber cab to frame line when cranking.and the frame to engine rubber line.

i would do everything that has been suggested. and clean the tank.