I got a load of lego from my cousin, and among this I found a 9V micromotor (2x2x2 red thingy). Unfortuenately it doesn't seem to work, nothing happens when I plug it to the battery case (with a FRESH battery). I measure about 100 ohms between contacts, so it seems like (at least some of) the coils are intact. The only I've found about the innards of these motors are
formatting link
(GIFs fail in some browsers). I was able to open the gear side of the motor (by using a razor blade to gently "tug" out the locking ring, it's not nescessary to cut away a large section as done on the page). This motor has a peculiar spirograph-like gear system with a wheel moved by an off-center motor axle, giving a 2300:1 ratio with just a few parts. The gears seems fine, but when i tried gripping (with pliers) and turning the little (off-center) motor axle, it seemed totally stuck. I've not been able to take apart the coil side of the motor, but it seems like the problem is there.
Has anyone else had any experience with this?
Axel