Is this normal functioning of a Seamaster cal. 1040?

I'm being pitched what is purportedly a Seamaster Yachting chronograph ref. no. 176.010 but I have my doubts about its originality. For one thing, when I pull the crown out and adjust the date there's resistance as though I'm winding the watch, and it even sounds like it's winding, making the ratcheting clicks. My 176.012 Speedy Mark 4.5 doesn't do this although that has a 1045 movement. Also, if the chrono is running and I pull the crown out to adjust the time (probably shouldn't do that) the central chrono minutes hand follows the regular time minutes hand around the dial. So if the chrono hand was, say, 15 minutes behind the minutes hand, it will follow the minutes hand as I adjust the time, always staying 15 minutes behind it. Again, my Speedy doesn't do this. On my Speedy, the chrono minutes hand stays put when the regular time minutes hand is adjusted. Can anyone say if either of these last 2 observations are normal for the 1040 movement? I appreciate your incite.

Hi, I have one of those, plus two other cal. 1040s. As for the date setting, that is how mine behave so I assume it is normal. I can't say I've ever tried setting the time with the chronograph running though. Do you have any pics?

I have recently had one of these apart and should get round to casing it at the weekend - I'll then create a thread about the service. I can confirm that the date setting is exactly how mine worked both before and after the service. Like Andy, I have never tried setting the time with the chronograph in motion.

Well you can't ask for better answers than that. Thank you. I think that gives a pretty solid indication that this is actually a 1040 movement because this watch casts doubts. The most puzzling thing is the back which isn't original. It has 12 sides instead of the 6 wrench notches that come with these watches. Actually, I've never seen a 12 sided back on any Omega watch. The inside of the back, I'm told, has the ref. number 125.003-62 which indicates that it's from a 1962 Seamaster 30. Even more puzzling is that the Seamaster 30 case is only 35mm, whereas this case back measures 36.5mm with an accurate digital micrometer. The 12 sides are very professionally cut. In the photos you can see machining ridges that run vertically in those edges. That must have been cast that way. If a back were cut afterward to remove the notches to add sides, it seems any machining ridges would run laterally. The ring around the seahorse isn't the same as any Seamaster 30 back photos I can find either. It's a real mystery.

The condition of the watch is mixed which leads me to beleive things have been replaced. The hands are quite corroded and have been repainted some time ago, which painted right over the lume in the minute and hour time hands. I suspect water damage, which makes sense if this was actually used for yacht timing. The dial is in very good condition though so I suspect it was replaced. Plus it's not exactly like the dials I see on 98% of online photos. Most, like Andy K's above, have indices with numbers imprinted in them. This dial instead has the features of it's sister Seamaster, as in JimInOz's. The number are separate from the indices, and those indices are rectangular. There's also the slight difference in the subdials (not including the color) and the 3 sided painted box around the date versus 4 sided. I suspect that Seamaster dial replaced the corroded Yachting dial. I think the crystal was also replaced since it has the tiny Omega logo in the center. I don't think those were used originally but I could be wrong.

Let's see if the experts here agree with the "experts" on WUS.

Yes, a complete difference of opinion between posters there. I wasn't really looking for the same advice here but since Andy K asked for photos I figured I may as well give the whole picture. I just wanted to know about the movement idiosyncrasies. They didn't address those at all there but I got great info here!

Agree, that caseback is just flat out wrong. Mine for reference and the benefit of others reading that aren't familiar with 176.0010:



I highlighted two interesting points you bring up regarding the dials. I've done a lot of research lately on cal.1040s but I've focused most of my attention on the steel versions, but based on what I've learned and what I see I agree with your assumption that this is not a correct dial for yachting chrono.

1. The indices are not typical of the 176.0010. I used to think this was the "decoder ring" for telling which dials were correct between the 176.007 and the 176.0010, but the gold ones were confusing. For example, the gold plated 176.007 did have a correct dial variant with numerals imprinted on the indices, which at first I thought was a "yachting" dial on a -007. But then I started to believe...

2. The box around the date window was the real decoder ring. This holds true for 7 of the 8 case references that used cal. 1040/1041. So my theory is that for ref. 176.0010, regardless of which case material or dial, all correct/original dials had a "closed" or 4-sided box around the window. For 176.007, all correct dials have an "open" or 3-sided window. Big Blue (176.004) had a closed window. 176.001, Mark III, Mark IV, the Speedmaster 125 have open windows. The one exception is the 176.005, which could have either.


I don't have a picture but mine does have a logo. The crystal should be significantly raised but has a sharp edge to it (not curved).

All in all I agree that there's too much that's incorrect, suspect, or in poor shape with this one and I'd pass.

This is great info and I appreciate it. The crystal is as you describe, but another Omega enthusiast told me the symbols weren't on crystals of that era. I haven't researched that myself and can't vouch for his "knowledge". Thanks again.

That must be the "expert" that stated that if a speedy pro doesn't have a screw -down crown it must be a fake, and thinks the 2531 is fake if it has a white date wheel.

Now I'm curious! But I can't seem to find the thread on WUS. Link?

EDIT: Found it in the Fake Busters subforum.

@Lancaster, after reading through the thread on WUS, I'll throw my (non-expert, but at least somewhat educated) opinion on a few points addressed over there:

1. I honestly don't know enough about crystals to be able to tell if the watch in question has an original or correct later replacement crystal, but nothing I've ever read would indicate that the originals from the period shouldn't have a logo. I have no idea what that guy is talking about.
2. You asked "The dial is at least a correct dial for the 176.007, but that's a much smaller watch. Can those dials fit into these larger Yachting's so precisely?" and I say yes, the dials fit well on either case. I've never seen measurements of the actual dials, but I've seen yachting dials on -007s as well as -007 dials in -0010 cases.

To me you've got a correct movement, case, crystal, and tachy ring. The caseback and dial are incorrect. The hands are bad enough that I'd prefer replacements. Tough call, but I'd still pass. The toughest parts to source are the case, caseback, and the dial and this example is missing two of the three.

The crystal on my GP 007 does not have an Omega logo but I have no way of telling if it is the original one or not.

All of the GP examples I have seen have either a gold dial or (like mine) the grey/gold, almost holographic dial - at some angles it looks grey and at others it looks gold.

Unfortunate specimen. It was already reported here:
https://omegaforums.net/threads/the-many-faces-of-evil.25990/

Thanks all. Andy I knew your death was a hoax.

Finally got it finished. You can see the insides of one here
https://omegaforums.net/threads/cal-1040-challenge-picture-heavy.27516/#navigation