At the cottage I draw water from the lake via a line with a foot valve, to a jet pump and on up to the house. The pipe has a heating cable through it, it we did have water running all winter on weekends we went up - so I don't think it was frozen The first day of our first spring trip all was fine. Next day...no water. I checked the pump house and the out line from the pump had come off. The pump was pumping out water, but obviously it was not getting to the house.
I refastened the lines, restarted the pump and it cycles on and off very fast - couple of seconds on, then a couple off. I though the pressure switch may have fried, so I replaced that. Same thing with the new one. Every once in a while the pump will catch and watter gets pumped up to the house, but it doesn't last long.
Today I pulled the line out of the lake. The line was full of water and the foot valve is OK. I took it off and cleaned it, and put it back.
I opened the prime hole, started the pump and go soaked by a geyser of water shooting about 5 feet into the air, so I think the suction line is intact
There is a valve just off the pump on the house side, and even if I close that valve the pump never builds up pressure enought to stop - it is the same on-off cycle as when it is pumping all the way up to the house.
I am stumped as to where to look next. Ideas?