Winding VERY stiff / Can't wind

[ColinC]

I have a watch with an ETA 2773 movement. It is possible to give it a bit of a wind from fully unwound using the crown but soon (after just a couple of turns)  the crown becomes too stiff to turn.

If I remove the automatic module the watch winds fine from the crown and can be wound infinitely (as should be the case with a barrel with an automatic mainspring installed).  

With the automatic module installed, I can turn the oscillating weight in both directions and see it correctly turn the ratchet wheel slowly in the right direction adding some wind to the mainspring.

I see that when I wind from the crown the reversing wheels move but the oscillating weight stays still.

I took the reversing wheels out and checked that the wheels were not jammed - the 2 wheels could  turn in opposite directions to each other smoothly and lock when turned against each other in the other direction.

Any idea what could be the issue?

[Marc]

Have you cleaned or oiled the reverser wheels at all?

[ColinC]

 

38 minutes ago, Marc said:

Have you cleaned or oiled the reverser wheels at all?

Yes they had a good soak in Lubetta and were allowed to dry for 30 mins or so before I installed them

[nevenbekriev]

Hi Colin,

If the reverse wheels are lubricated as needed, then another possible reason is they are weared. The wear is in the bearing table/pinion and may be in a manner that the table of the wheel can be tilted on the pinion and thus may rubb on the table of the wheel that connects the both reverse wheels pinions or somewhere else. Another kind of wear is when big radial free play of  table/pinion bearings is present, in such case the mesh of the wheels is not normal and may cause friction.

Edited June 10, 2024 by nevenbekriev

[Marc]

10 hours ago, ColinC said:

 

Yes they had a good soak in Lubetta and were allowed to dry for 30 mins or so before I installed them

@nevenbekriev has already voiced where I was going next. The primary cause of the kind of symptoms you describe is either worn or sticky reverser wheels. I believe that at one point ETA's policy was simply to replace them at each service. If they've been cleaned and properly lubricated but the problem still persists then my next step would be to replace them.

[ColinC]

Thanks for the suggestions - everything I have read points to the reversing wheels.  I will take them out, inspect, re-clean and lubricate them.  I didn't see any wear on the plates of the automatic mechanism  but will look more closely at the wheels themselves.

[ColinC]

After a good soak in IPA and tickle with an artist’s brush and then another dip in Lubetta the reversing wheels are back in the watch and working a lot better!

[mikepilk]

I recently had exactly the same problem on an ETA 2773. Cousins don't stock the reversers any more, but I found another cleaning cycle made things much better. 

I had been using my own mix of lubricant - 9010/naphtha, but now I've switched to Lubetta I'm getting more consistent results