On 2011-02-26, Baron wrote:
Sylvia Else Inscribed thus:

I'd have to wonder whether one of the rotor windings has failed
open-cicuit. I think that could even account for the sparks. The
magnetic field for a winding that is becoming disconnected by the
brush action has to collapse because the broken winding that's being
connected cannot maintain the field.

Sounds like OC segments on the comm...

The old man and I don't know enough about motors to be sure but
we did suspect something along the same lines.

We thought that even if we determined which winding is damaged,
attempting a fix would be risky and a lot of work. So we got a
used (but working) motor from electrodocas.fr. That fixed it.

Thanks folks.

--
André Majorel http://www.teaser.fr/~amajorel/
"The object of this year's expedition is to see if we can find
trace of last year's expedition."