
The original owner of this Longines ultra-chron has sent it in to be repaired. He remembers getting it as a gift when he was 15 back in 1974! He has the choice of a Certina DS and this Longines. He was very into his model aircraft flying and the aviation fuel once leaked into the watch creating a very unique patina on the dial and hands. It’s not keeping time and needs a service.

Movement looks to be in lovely condition.

The dial actually looks pretty great and would be impossible to replicate.

Here you can see the date disk.

Setting/winding mechanism.

I take the base movement apart.

Hmmm yeah right…

I remove the mainspring to clean it.

The Longines calibre 431 all in parts and ready to be put back together.

I see that the balance moves freely after fitting the shock protection jewels.

I fit the cleaned and oiled mainspring back into the barrel.

I fit the setting/winding mechanism.

Base movement back together and ticking.

I’m very happy with that!

Movement ready for dial and hands. I have tightened the cannon pinion clutch that was loose.

The dial and hands back on the movement.

Movement back in the case.

I put together the auto winder mechanism.

Auto winder mechanism goes back in place.

The ball bearing was a little slack so I tighten that. I then fit the osculating weight into the movement.
Certainly a unique Ultra-Chron!
1 Response to Service: Longines Ultra-Chron. Calibre 341
Hi Mika, beautiful piece and great work as always. If I may ask you a question? What lubricant do you use on the auto winding mechanism?
Thanks,
Gary