Speedmaster Z-33 losing analog time

There should be an expiry date on the battery package:



In this case January of 2018. I recommend buying batteries only from locations with very high stock turnover.

However I'm not convinced this is related to the battery age. I'm assuming you changed this yourself? Did you put the watch in the battery change mode before removing the old battery? Did you position the contact spring in the battery insulator opening?

Well, at this point I think you will have to take it in to Omega to have them diagnose what the issue is. Although changing a batter seems like a simple thing to do, it's not always the case. These watches in particular have more things that can go wrong compared to a simple analog quartz watch, so I don't consider this one a DIY job.

All it takes is a small spec of something from the case back dropping into the movement, a slip of something damaging a coil, incorrect procedures, and things can go wrong.

Cheers, Al