How can you replace a Goulds Jo5N Jet pump with something quieter?

Answer 1

If the pump is just loud, you should be able to simply replace the power unit. Some jet pumps have the jet separate from the power unit. If this is the case you will have to make sure that the pump matches your jet if you will not or cannot replace it. Otherwise just throw a new pump in there. You'll have to do some re-Plumbing in any case, so if your pump is in cramped quarters make sure you can plumb the new pump.

The power run to the pump should be considered as well. For the least amount of headaches, make sure the voltage is the same and the current draw is the same or less. This will prevent problems with your pressure switch and wiring. I don't have too much experience with well pumps, but for large stationary appliances, 220V is generally better. The motor has more power run to it so it doesn't have to work as hard. This results in less current being needed by the motor. If your pump is currently 110V your pressure switch should be okay, as it will have to carry less current, but you will need a new breaker. If you didn't understand everything that I said above, or if you have any doubts, hire an electrician.

Ans 2 - If any jet pump is loud enough to hear upstairs then there is something wrong with it. -It's common for bearings to dry out and become noisy on the motor. Also if the pump has run dry in the water chamber for a few occasions then the impeller can warp and make a dull scraping noise.

If you know the pump has been in more than 10 years then it very likely needs servicing.