Girard-Perregaux Stops When Still

[WillFly]

My mid 1960s cal.23 Girard-Perregaux is annoying me. It keeps excellent time when on the wrist. The movement's not too dry and it's not over-oiled.

 

When it's lying flat, it stops. A gentle movement starts it immediately, then it goes for a while then stops - no particular regular interval, just when it feels like it.

 

Any discernable cause?  Advice and comment welcomed.

 

Will

[Geo]

Probably just needing a good service Will. Do you know when it was last serviced?

[WillFly]

Yes - very recently - that's the annoying part.

[bobm12]

Sorry to hear that Will, I was thinking of a cracked jewel or weak main spring? Maybe there is still some caked oil somewhere that was not properly removed when serviced?

[Geo]

Maybe there is still some caked oil somewhere that was not properly removed when serviced?

My money is on this, it caught me out when I first started watch repair.

Edited February 15, 2015 by Geo

[WillFly]

It's certainly a possibility - the watch was incredibly dry when opened up for a service. I'll get it checked out again. Thanks chaps.

[CKelly]

Hi,

   I've been sitting here working on battery power and generator due to power outage and high winds. Anyway I saw this post and started thinking a bit. One thing that comes to mind is cap stone on balance cock may be a bit dry. That pivot point may also be a bit gummy still which would show as an issue you described. Another odd possibility is that there is, if I remember properly, a center sweep pinion that is held in place by a tension spring. This spring might be allowing the center sweep pinion to drop a bit causing it to bind just a bit which would stop the watch and this could show up when watch was in face up position. That seems to be a stretch but I have seen a similar issue in the past.

Charles K

[bobm12]

Interesting! How about a cap jewel upside down?

[Geo]

Interesting! How about a cap jewel upside down?

Would that not take up the end shake and make it tight in all positions?

[bobm12]

That's true, never got that far in my "troubleshooting" thoughts! :)