GMT Hand doesn't beat - Something thats fixable?

[VesperMatt]

Hey guys,

After I saw what Donerix was able to do with PT's 6542 I picked one up to do some light modding on/learn on. Got it today and the GMT hand doesn't beat/move with the rest of the movement. Hours/minutes/seconds, however, is keeping perfect time. I can manually adjust the GMT hand (as well as the date) from the correct position and when I manually adjust the hours & minutes, the GMT hand also adjusts in synch. But when the crown is fully screwed in, the GMT hand doesn't budge at all.

I did a search and I saw mention of the GMT hand slipping and some other people having problems... I suppose what I really want to ask is if its something I could check/correct myself (I have a set of tools from Watchbitz) or if its something that would be not too expensively remedied when I send the watch to get the movement serviced, as I intended to do. Trying to avoid shipping this thing back to China.

Assuming thats not too big of a deal, does anyone know a source for a better GMT hand? Would the Yuki hand set for ETA 2824 fit the ETA 2846 in this watch?

[Ronin]

It might not be the hand but a missing tension washer between the 24hr gear and the hour/dial.

When you manually set it, you are engaging a different drive mechanism. The fact the hand moves when in that mode, tells me it is not the hand.

[sneed12]

What movement is it?

The GMT wheel sits on top of the movement, and it needs some pressure against the movement to stay connected to the calendar gear. Like Ronin says, if the tension washer is missing/out of place/got flattened it won't work.

Easiest thing to do is just take it apart and put it back together. If nothing is actually broken that should fix it.

[sneed12]

When you manually set it, you are engaging a different drive mechanism. The fact the hand moves when in that mode, tells me it is not the hand.

Could still be the wheel. The two parts are designed to slip against each other, if the tension between the parts is not just right they won't stay together.

[freddy333]

When setting the time, does your gmt hand move like this

[VesperMatt]

Left it overnight and didn't mess with it. Just picked it up now to reply and the GMT hand no longer moves more than a mm or two when I adjust the hour and minutes. It will move a tick and then stops moving with the other hands. Date changed over fine at night.

The movement is supposed to be an ETA 2846. If I pull the crown out, the first stop I can turn the crown counter-clockwise and it will it in turn move the GMT hand counter clockwise. That still works, although I've gathered from you guys its a separate gear than what actually makes it tick.

I guess tonight I'll take the caseback off and try Sneed's advice of assembly/dis-assembly. Whatever it is, it sounds like if I can't do it a competent watch smith should be able to fix it right? Not a serious enough reason to send it back?

[Ronin]

Sounds like something is amiss in the 28x6 GMT Modification. Long short, you need to pull the movement, hands, dial, and poke around. If you are not capable, some other members here are.