Keyless works and date jumper struggles, AS 1916.

[Hibbz]

I bought a vintage Favre Leuba watch off ebay and only realised on reassembly that some parts were missing, which meant the date jumper function wasn't working. Managed to get hold of the parts I thought I needed to fix this (unlocking yoke lever, setting lever return spring), but it still doesn't operate and I'm not sure how it should function mechanically? I could be missing something else as I can't quite figure it out and Im not sure how it resets itself after being operated? Have a look at the images and if anyone can tell me where I'm/its going wrong I'd be very grateful.

 

 

Edited December 19, 2021 by Hibbz

[Marc]

See if any of these help

[Gaus]

Is the jumper function bij pressing the crown in?

[Hibbz]

Thanks, I can't distinguish a difference between what I've done and the pictures you've supplied. 

From what I can tell when the crown is depressed the setting lever is meant to pivot against the unlocking lock lever, that then moves forward and should interact with unlocking yoke for the date indicator, which should then advance the date wheel. 

Currently the unlocking yoke lever doesn't always sit in a position whereby the setting lever can activate it and it doesn't have any interaction with the yoke for date indicator?

The unlocking yoke lever is also contacting the pallet fork when fully depressed, possibly because one of the combined bridge screws are too short, again I'm not sure, but Im going off what I can see in your pictures.

*Follow up, when I put it back together the calendar wheel does move if i rotate the crown through 24 hours, but no quick set function??

Frustrating as I wanna give it some wrist time.

PS think the calendar driver is upside down in that pic?

[Marc]

Do you have the parts indicated below? I don't see them in your pics, these are the parts that interact with the date wheel.

I don't know which part you think is upside down but this was fully functional.

[Hibbz]

Ah okay, must be my error. That part on mine looks slightly different? See below  

And yes I’m pretty sure jumper function is by pressing the crown. 

 

[Hibbz]

Yours must have a day date function. 

[Marc]

2 minutes ago, Hibbz said:

Yours must have a day date function

The 1916 is a day/date movement. I assume that yours is date only which is why the calendar driving wheel looks different; the finger visible on mine is what changes the day. If yours is date ony then it isn't a 1916, but rather a 1913 (assuming it's an auto). However, AS also did a 1902 which was the same but without the quick set function. I'm wondering if what you've got is a 1902 which is why the quickset parts were missing in the first place.

I can't quite tell from your pic, but when you push the stem in does the corner of the set lever (red arrow) interact with the end of the unlocking yoke lever? It may just be the angle of the pic but it looks as though it may miss.

[Hibbz]

Yes its an auto with date only function, the plate is stamped with 1916, so I've been going off that.

It does interact but only if the unlocking yoke lever is in the correct position, thats part of my issue, Im not sure how this part of the mechanism is meant to work.

How does the yoke lever reset after the stem is depressed and how does it advance the date wheel?

[Hibbz]

So I got to the bottom of it and it makes sense now. The unlocking yoke for date indicator was damaged and missing a vital pivot underneath which makes that whole part of the mechanism operate. See the picture of the new part below. I will post a picture of the watch once it’s back together!