My GMT Master II Z series did the same thing.
I did more tests and after you removed it off the wrist it stopped working after 4 hours. As soon as you move it a few times it starts up again for a minute or so.
I decided to talk to the reputable high end watch dealer in Montreal where I purchased it. They kept it in a watch winder for 24hrs and then stopped the winder for a few hours. The GMT stopped ticking after about two hours. They have sent it for repair.
Waiting for the prognostics.

__________________
GMT Master II Pepsi ... Z Series
GMT Master IIc TT 116713 LN ... V Series
Submariner Date ... V Series
GMT Master IIc 116710 LN
Patek Philippe, Panerai, Zenith, Breitling, Oris, Fortis, IWC, Seiko
|