Patent ID: 7265468

Claim:
A motor, comprising: a housing; a bracket; an outboard bearing supported by the bracket; an inboard bearing comprising an inner race and an outer race, wherein the outer race is radially supported within the housing; a rotor with a rotor shaft having an outboard end and an inboard end, wherein the inboard end is supported by the inboard bearing, and the outboard end is supported by the inner race of the outboard bearing; a stator encircling the rotor and being interposed between the housing and the bracket; a tubular spacer attached to the inboard end of the rotor shaft; an impeller attached to the inboard end of the rotor shaft such that the tubular spacer is interposed between the impeller and the inboard bearing; a threaded nut attached to the inboard end of the rotor shaft such that the impeller and the tubular spacer are axially clamped between the threaded nut and the inner race of the inboard bearing to provide a predetermined axial spacing between the impeller and the inner race of the inboard bearing; and a water repellent sleeve encircling the tubular spacer, extending axially between the impeller and the inboard bearing, and being situated so as not to contribute to the predetermined axial spacing between the impeller and the inner race of the inboard bearing, wherein the water repellent sleeve has a lower solid surface energy than that of the tubular spacer.