Been doing some reading about this motor. From what I've read, the manufacturers consider it a disposable motor. There is a comment in the manual about replacing it ( the whole motor ) if any corrosion shows on any of the commutator slats. No mention of cleaning it, just toss it and put in a new one.
Ugh, now I need to find one. Sears doesn't have them any more, so where to start looking?
Joe