The bowl in the tank is called a splash bowl, take a look here and it will explain it's function.
http://www.mbca.org/northtexas/fuel_system.htm
Hmmm, maybe I would remove the access to the tank and inspect it. I have never heard of any of the lines coming loose or getting bent, but if the pump is sucking air then that is the only thing it could be, the line either came loose from the splash bowl, or it is clogged. I am not entirely familiar with that model, but the more I think about it it sounds like a fuel pump. Where is the pump located? I would park it on an incline, at failure (not starting) remove the pump from the chassis and decrease the angle of the pump and see if it starts to pull fuel. If that is the case, it is something wrong with the pump, if it doesn't pull fuel, but is running, then you may have a tank issue and that will involve removing the access panel and inspecting the inside of the tank, it is unlikely anything has come loose in there, but it is possible. Good luck.
Brian