On Mon, 21 Jan 2008 20:48:15 -0000, "Graham." wrote:


When I had the same problem it was carbon deposits on the plastic
brush-carriers.

Hmm, well I think they were new when I did similar last and certainly
they are much much younger than when it happened the first time from
new. Today I gave them a good wipe over and like I said, there seems
to be no measurable resistance between the brushes / rotor and the
motor ground (in contrast to the stator and ground). :-(

With the action you have outlined you will find the cause easily.

Well I think I have found the general area but not the cause per-se.

FWIW I would like to carefully take the motor further apart and just
see if I can see where 18K could exist.

All the best ..

T i m