Dynamic - service required...

I’m trying to find out as much as I can about a Dynamic that my wife really loves the look of. The seller has checked for me and it is currently working for 6-7 hours at a time only, losing about ten minutes each time.

Would this be just a mainspring issue, or possibly something more sinister? I understand that it will require a service, and that access to the movement of these is a bit tricky, so am wondering if it will all be worth it (to be reflected in my potential offer).

Thanks for any advice, good folk of OF.

Movement access is actually pretty straight forward, once you know how to do it:

Crystal comes off (Omega Tool 107 for the ladies models)

Crown and stem come out

(Tricky part) Use tweezers to rotate the movement in the case about 30 degrees (you'll see notches in the dial once the crystal is removed)

Turn the case over and the movement drops right out.

The whole mechanism is quite clever, the recesses of the case act as a movement holder.

The good thing is that movements tend to be less mucked around with since they're not accessed in an obvious way. I've bought two so far (one for myself and one for my mom for Christmas because she liked mine so much) and the movements have looked pristine. Personally, I'd buy the best looking one you can find in your budget, and then get it serviced, since Omega used workhorse calibres (681/684/etc) Which are still pretty straightforward to get parts for

From WatchRepairChannel:

Here is a demonstration of male dynamic. WatchRepairChannel makes it seem very easy but there is section from when Mark removed the crown to the rotation of the dial where it is not obvious what to do. Be careful you don’t destroy the o ring underneath crystal as you will have to buy new crystal.

This video is for demonstration and I don’t have an opinion or qualifier on the matter otherwise.

Good luck!