Questions about the water system on my '74 25' Tradewinds

[chuman70]

I just bought a 1974 25' Tradewinds Land yacht and have been slowly working on getting it ready for camping this year. It has a lot of problems, but I guess that is to be expected with a 30+ year old camper. My concern right now is that I have filled the water tank and when I turned on the water pump, it just runs and runs and no water comes out. I am brand new to Airstreaming and was wondering if anyone could help me figure out why the water will not run. May be a stupid question, but I cannot find anything tin the manual that helps me. There are 3 valves under my kitchen sink and I'm not sure what they do or whether or not they should open or closed. Also, there is a tube under the belly of the trailer that is running water constantly. Is that possibly why I cannot build up pressure? I wondered if the pump had to be primed as well. I looked at it while it was running and I could see that there was no water running through the hoses. Any help would be MUCH appreciated.

[Wabbiteer]

My '73 has a brass check valve on elbow coming out of FW tank basement feeding pump intake that sticks closed - I primed pump, tried everything but it only allowed water to flow after rapping the fitting with a big wrench. The fitting looks a little like some of the gas-line compression nuts except it is about 1 1/2 inches long. Also at that point had the original strainer cup gasket fail so it would suck air from there - R/R the old one ...

[chuman70]

Do you have a picture of what that looks like?