And the hose was clear of obstructions? No cracks? Hmmm.... Well if it is clear of obstructions, try lifting the hose up and pour in some gas, and have someone spin the motor over a few times, to see if it pumps. maybe it needs to be primed, like you said. For that rust in the carb body, you can steel wool it, then blow that off, and or put a little oil in it, and a half a hand full of bb's or number 4 bird shot, and place the piece on a vibrator, and it will be clean of rust in short order. A Friend of mine owns a marina, and their mechanic uses that technique to clean metal gas tanks, that are rusted inside.
Wayne