Econoline is the Ford van it is built on. Leisure Craft is the RV brand. Ford doesn't put in water tanks/lines, etc. Could you post a photo of the area where the water lines connect, so we can see what you have?
Generally there will not be a shut-off valve that prevents the city water connection from supply the RV, so I suspect you have a stuck or damaged check valve at the inlet. It's part of the fitting where the hose screws in.
How does the fresh water tank get filled on this RV? Is there a filler port on the side somewhere? If so, add some water to the tank and tun on the water pump and see if you get water tat way. There will be a drain for the tank somewhere, but I have no clue where it might be on your particular RV. The variety is almost infinite!
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL