Jet pump systems

A pump assembly includes an electric motor including a rotor having a shaft extending from the electric motor, the shaft including a substantially single unit of material and having an end rotationally couplable to an impeller that when the shaft is rotatably displaced by the electric motor, the impeller displaces a fluid to create a jet of fluid. An enclosure having a cavity arranged between a front surface and a back surface of the enclosure, and the electric motor being arrangeable in the cavity of the enclosure. The enclosure protecting the electric motor arranged in the enclosure from a fluid, and a dielectric fluid is containable in the cavity of the enclosure to immerse the electric motor in the dielectric fluid for preventing corrosion of the electric motor from the fluid.