thats just your breather tube, nothing to worry about, this is going to sound stupid, but do you have your bowl facing the right way? the deep end goes where the float hangs down, if you dont have it on the right way it keeps the float up constantly, stopping gas flow and you get nothing, also those gaskets look thin as hell, id suggest going to your mower shop and getting all the gaskets, another problem could be your fuel line, i had mine run like that and it didnt pickup gas for ****, you have to remember this gas tanks works off of gravity, not like a fuel pump, drain gas from the tank, take your fuel line and push it under the bolt on the flywheel shroud, down through the hole made for it on the black peice your carb pushes against, and make sure its not restricted, this is gravity, it dosent suck it out of the tank, it just comes down the line into the carb