2 line jet pump won't build pressure

[Hiker trash]

We have a 2 line jet pump in our house that we have owned for 20 years. Just in the last week the pressure switch wasn't shutting the pump off so naturally I replaced it. But then the pump would run but the tank wouldn't pressurize so I replaced that. Now the pump runs water will come out but at such low pressure that it only trickles out of the faucet. It seems to be holding it prime . I manually shut it off at around 30 lbs because it just keeps running and won't build any higher. Any ideas?

 

[Reach4]

Your jet is down the hole. It may be clogged.

Maybe the pump is failing.

I don't know the best way to distinguish.