As Dunbar suggests, your problem may be due to a waterlogged tank. In general, what this means is that your pump “sees” a rapid build up of pressure and shuts off via the pressure switch. I could be a waterlogged tank. However it could also be anything else that leads to a rapid build up of pressure in the pump outflow circuit, such as a blocked line from the pump to the tank. What I’d do in such a case is disconnect the pump outflow to the tank, actuate the pump, and see if you get a good flow of water. The pump should run freely and not shut off…water should just shoot out of the pipe (Be sure to have someplace for it to go). If that’s the case, your problem is in the system after the tank inlet connection. If you still have the same problem after disconnecting the tank from the well pipe, the problem must be anywhere from the pump itself to the connection between the well pipe and the tank. happy hunting.