Hi Dave,

Those early Faller motors are a surprisingly simple design. Basically they rely on the changing wave-cycle of AC power, hence they won't work on DC. That's the first important detail and it might be just that.

The disk sits against the small bristles (the fluffy stuff) and their sole purpose is to keep the motor going in just one direction. There are no cogs as such. It should look similar to mine below (exploded). The screw in the black arm is to control the speed.

There is really only one thing that goes wrong with them and that's the thin rubber film in the centre of the disk. They simply wear out and become elongated so that the axle is no longer gripped.

But... I would first test it with AC because that's my guess why it's not working.

If the disk rubber is worn, (I haven't tried this myself but I know the motor style very well), if you could find some rubber sheet of similar thickness you might try gluing it over the worn portion, pierce a new hole in the centre and push the axle through

If the motor is truly kaput, you can usually find replacements on ebay etc, or even here. And there are modern versions that do the same thing, #629, or 180629. A few kits have very limited space where the newer motor may not fit.

Hope this helps.

Thanks Cookie, I'll see if I can replace that rubber centre bit.
I did try it on AC (although I forgot to mention that in my OP)
and got exactly the same result.

As I mentioned, it does try and turn and you can see the windmill
blades moving very slightly so I think the motor is working.

Excellent Marco. I will try the bicycle patch cure tomorrow. Thanks.