"Jerry G." wrote in message
...
| This goes back a long way for me, since I am a bit of an old timer from
that
| era.
|
| If I remember right, the speed control moves an idler wheel up and down a
| stepped shaft on an AC mains synchronous motor. The lubrication is most
| likely dried out, and probably some parts require some changing due to
| deteriation from age. Even in the old days when I used to service these,
it
| was very common that the idler wheel would have to be changed. I would
have
| no idea of where you would find parts for this.

Sometimes you can 'revive' the wheel but with nasty chemicals. I bet you
can't buy the proper dope any more!

N