I replaced the belt-driven pump on my 32' with a Jabsco unit that does not require an accumulator, and it is very nice.
However, I left the water pressure switch on when leaving the boat for a couple of months, and the water ran out and the pump tried to pump air until the motor failed. It says it can "run dry", and it can as far as the pump part is concerned, but it will spin like crazy with no load, and that's the end of the motor.
I machined the commutator and replaced the brushes and springs, but it wasn't easy. I couldn't find replacement brushes, so I machined down some larger ones that I had around. All in all, it took a whole day. And it took a lathe and a milling machine, stuff most folks don't have.
Since there is an electronics module in the pump anyway, one would think that Jabsco would put in some sort of shutoff, but they don't. I am making a shutoff from a relay, delay timer, and pressure switch that should take care of it. Meanwhile, "shut off water pressure" is on my "De-commission Checklist".
1975 32' Flybridge Sedan, twin Perkins 6-354 diesels, 1:1.53 velvetdrives, 16 X 19 props. Merritt Island, Florida