Yes I can confirm that. I have had mine cut out and then start working. The problem in the OP is probably as already mentioned, that it has become burned out in one section OR the carbon brushes have become worn enough to only connect sometimes. Gently tapping the motor with power connected often shows up this fault. As I say, I have a pal who can probably rewind/repair these. I would need one to show him to get a price and an idea of replacement costs otherwise.
