No water flow when dry camping

Two simple tests. One, loosen the line from the intake on the pump and see if water flows out. If it doesn't the line from the tank to the pump is plugged, either at a filter or at a fitting. If it flows, hook it back up and disconnect the outlet line from the pump and connect a hose to it and see if it pumps water out. If it does, you have an obstruction between the pump line and where it connects to the house plumbing. If it doesn't, the problem is at the pump and the most likely problem since you changed pumps is the connection at the intake. If it does not seal up airtight, the pump will suck air and not pump efficiently. This problem happened on my diesel pusher. The shop that winterized it, cross-threaded the connector. It didn't leak water, but didn't create a complete suction so the pump wouldn't pump water. Simple fix was to put in a new washer, make sure it threaded correctly and tightened up. Worked like a charm.