Well pump keeps running @ 70psi

I'm new here and also to the well thing so please bear with me. I have a well that is 25' deep with a shallow well pump. Last year I replaced the well pump because the one that was there burnt out. I have replaced the well pump pressure switch ( 40-60psi )twice thinking it was faulty. I have checked the pressure in my tank with no water pressure in it and found it was a little low and set it to 38 psi. I started everything back up and still the pump will not shut off at 70 psi. I have tried to back the nut off at the large spring to see if it would help but I just about took the nut off when it would shut off. Then problem was it would not turn back on so I returned the nut to it's original position. I am I missing something here? Any help? Thanks, Mike

have you ever cleaned the 1/4" nipple that the switch connects to?

If it is clogged it will not allow the switch to work right.

It would always be on.

I replaced both 1/4" nipples and the tubing already and still no change.

Have you checked to see that the gauge is accurate? I'm not sure what you mean that it won't turn off at 70 psi. Most jet pumps won't make 70 psi. If you cranked the nut almost off the tall screw, where was the short springs nut?

bob...