Restoration - Talking doll mechanism

This is not a usual "repair".
At an antique mall we found a Italian doll made around the seventies, a "talking" doll !

Assessment

The doll is "almost" in mint conditions, i.e. the box was opened and somebody put a 1.5V battery in the mechanism, so somebody used it or at least did try to use it, however the rest of the doll clearly it was never used.

The doll has a "disk", like a vinile disk but made in plastic and a mechanism to read the disk.
Amazingly there is no electronic ! No amplifier, no control of the motor.
Basically it is a 1.5V electric motor that spin a platform where the disk is mounted and a stylus that follow the disk grooves.
However there is no electronics to amplify and treat the signal, i.e. the stylus is not converting the mechanical movement in electricity !

The signal from the stylus is "amplified" mechanically and applied to a "speaker" hold by a spring.
The speaker is simply a movable plastic disk hooked to the stylus, so the vibrations of the stylus are applied to the speaker.

Of course is not possible to expect a quality reproduction of the recorded audio with such system however the result is astounding !!

Repair disk mechanism

The mechanism is inserted in the doll but is not screwed or glued, so it is easy to remove it.
Once removed, is did start to check it out.

The mechanism did stay off for long time and the battery was left inserted, so of course the first thing to do was to clean up the connectors.
Only the one touching the negative of the battery was totally oxidized and loaded with battery acid.

I had to remove it with some pointy metal and then with some sandpaper.

Inserting a new battery however didn't produce any movement.

Before to take apart the mechanism, that involve break some glued parts and break some plastic supports, I forced manually the motor to spin.
To do so I did take a ear cleaner (cotton fioc), cut out one part and used the small obtained pipe to fit the motor axle.

When a small motor is not working for a long time, build up some dirt, enough to block the motor.
Forcing manually to rotate clean up little bit the internal part of the motor.

That was enough to restore the mechanism.