Record 107c puzzler of the day

[cduke]

Hello all with best wishes for a great holiday season and end of year,

My puzzler today involves a record 107c movement in a Kingston watch datofix.

The stem turns the ratchet wheel when winding but the watch runs only when the screw of the ratchet wheel is turned.  Obviously the stem is not winding the spring but the screw is. Anyone know what may be happening here. Just replaced the stem with no difference. The winding does not sound “smooth” but is a little louder than would be expected.

 Thanks 

chris

[WatchMaker]

A likely reason is that the square hole in the ratchet wheel has become rounded and is therefore not engaged properly with the barrel arbor. The stem may well result in the turning of the ratchet wheel as expected but  this may not actually be turning the barrel arbor properly. [However because the screw is directly in the arbor then if you use this method then the winding does seem to work]. Also obviously check that the ratchet wheel is properly seated.

Initially I would suggest removing the ratchet wheel screw and gently turning the stem and observe what happens to the arbor and ratchet wheel. [The ratchet wheel should not pop off in the absence of the screw if you are gentle but if in doubt you can always hold the wheel in place with (brass) tweezers].

[oldhippy]

I would remove the dial and hands and look at the keyless work.