I have a 2007 Excursion 39V and cannot fill the fresh water tank through the passenger side port.  Water from a hose goes in okay for a couple of minutes and then spits back out the port and will not take any more water.  It acts like the tank is full but it is almost empty.  I can fill the tank without any problem if I use the hose connection and fill valve on the driver's side of the coach.  Any suggestions?