shallow well pump pressure

Hello Terry,
My pump pressure gauge is maxing @ 40psi at our summer home. For the last 10 yrs it operates between 30 and 50 psi. Today I had to prime with a pitchur pump as the well would not prime, it primed very quickly with fhe hand pump. It maxed at 40 psi and would not satisfy the pressure switch,
I increased air pressure on the pressure tank and it satisfied 1 time, openend a valve until pump kicked it on again only reached 40psi. Then I adjusted the pressure switch to shut off at 40 psi. Now it is operating between 25 and 40psi. Is my tank failing or the pump or is it the pressure switch? I know I have too much air in the tank now but is operating. Please help beforeI replace everything. Thanks , Shamus

You need the correct air in the pressure tank; that's 29-28 psi for a 30/50 switch setting, with no water in the tank. Right now the pump is pushing against more compressed air than it is supposed to be for your switch setting. You can't troubleshoot until you get that part right.

When the tank is drained, remove and clean or replace the gauge so you can depend on what it tells you.

Your problem can not be the tank or switch, unless there is rust build up in the switch or tubing or tubing fittings going to or from it, and the holes the fittings screw into.

Otherwise, you don't have enough water in the well or, the jet in the pump is blocked, or there is a leak in the pipe from the foot valve to the pump or, the screen on the foot valve inlet is partially blocked.

If there are two lines from the pump to the well, the jet is in the j-body in the well. If one line, the jet is in the wet end of the pump, usually inline with the water line from the well.