Corrosion/chips around seal

AHW · Jan 29, 2026

Hi all,

How concerned should I be about the corrosion or damage on the outer case edge that goes around the seal of this Speedmaster that I am considering purchasing? In places it appears that the case edge has been completely eaten through so that the seal might be exposed.

My main concern is water tightness as I want a watch to wear. In terms of moisture the movement looks very clean to my eyes. There are areas of what appears to be minor surface corrosion on the case.

The tritium hands have gone black which to my understanding indicates mold, but the tritium on the dial is tan. The condition of the dial itself is hard to access due to a very scratched hesalite.

Any guidance would be appreciated!

Thanks.

hen · Jan 29, 2026

As a mechanic I would say that as long as the sealing surfaces (The surfaces the o-ring seals against) are clean and without corrosion it will stay water tight.

(Watch makers may have a different opinion)

speedb · Jan 29, 2026

Pitting on older stainless steel watches does happen and is one of the reasons why older watches should not be considered water resistant. If you want to have more of a solid idea of how waterproof it is then you will have to get it tested by a watchmaker.

Canuck · Jan 29, 2026

You really need to see whether there is corrosion UNDER the “O” ring gasket. As well as the possibility of corrosion around the perimeter of the case back where it contacts the O ring.

Dan S · Jan 29, 2026

Can you remove the o-ring and post photos of the groove. And also of the flange on the caseback. Those are the sealing surfaces.

ErichKeane · Jan 29, 2026

hen
As a mechanic I would say that as long as the sealing surfaces (The surfaces the o-ring seals against) are clean and without corrosion it will stay water tight.

(Watch makers may have a different opinion)

THIS for the most part. Though having done a bunch of machining in the past (hydraulics/steam/etc), with thinner o-rings, if they aren't supported 'enough' around the outside they tend to try to 'migrate' and pinch their way outwards, which can cause areas for water ingress. I'm not experienced enough to know what 'enough' means in that last sentence 😀

Canuck · Jan 29, 2026

The seal around the case back is not the only concern. Crown, pushers, crystal, all have to seal as well.

AHW · Jan 29, 2026

Thanks all for the feedback. The caseback looks pretty good. Only a couple of locations of what looks like dirt or very minor surface corrosion.

I can ask the seller if they are willing to remove the o-ring, but I am leaning towards passing on this watch unless I can get it for a very good price. Seems a little risky given that I cannot really see the condition of the dial when there is a risk of moisture/contamination.

Davidt · Jan 29, 2026

Not many people would consider a vintage Speedmaster water resistant even without any pitting.

Regarding value, if the case has pitting around the caseback threads, the hands have dark lume and it’s not possible to assess the dial, it’s likely to be towards the lower end of the value range. That said, overall case and dial condition have a larger impact on value. So you have any pics of the whole watch?

AHW · Jan 29, 2026

Davidt
Not many people would consider a vintage Speedmaster water resistant even without any pitting.

Regarding value, if the case has pitting around the caseback threads, the hands have dark lume and it’s not possible to assess the dial, it’s likely to be towards the lower end of the value range. That said, overall case and dial condition have a larger impact on value. So you have any pics of the whole watch?

Of course. No plans on any deep sea exploration, but I don’t want to have to run in a panic to the watchmaker if I splash the watch washing my hands either! The oldest watch I have ever bought is from 2000 so these issues are a little unknown to me.

This is definitely at the lower end (145.012) and I wouldn’t be willing to pay the advertised price either, but my initial thought is that a new hesalite + a clean/potentially a light polish and it would come out quite nicely. To me the case seems quite sharp, but a bit tired. Bezel is ok and all the components seem correct.

If I like the watch after the initial cleaning I would maybe replace/relume the hands. The big question mark is the dial as I cannot judge it other than the lume is quite a nice colour. And my moisture concerns as there is a fair bit of corrosion.

Archer · Jan 29, 2026

You really need to see the groove that the o-ring is sitting in to make a real judgement. But given the pitting that is already visible, it wouldn’t surprise me to find pitting in the groove and on the corresponding mating surface of the case back.

I service a lot of vintage Speedmasters, and a very high percentage of them can be made water resistant again, as long as the groove and case back are good. I’ve only rarely had another location that was a problem…I do recall one watch that had one pit where the crystal seated, and that prevented it from being water resistant.

I would say 90% of the vintage Speedmasters I service are able to be made water resistant again. This does often require replacing other parts as well, such as pushers and crown.

Dan S · Jan 29, 2026

The water resistance would probably be one of my lesser concerns in terms of valuation. The dial might end up being decent, with perhaps a bit of lost lume, but the rest of the watch is very rough. It would have to be very cheap and you'd need to be in the mood for a project. Just recognize that no matter what you do, it's never going to be a good example.

Given that these look like professional photos, I strongly suspect that the value proposition is not there.

AHW · Jan 30, 2026

Dan S
The water resistance would probably be one of my lesser concerns in terms of valuation. The dial might end up being decent, with perhaps a bit of lost lume, but the rest of the watch is very rough. It would have to be very cheap and you'd need to be in the mood for a project. Just recognize that no matter what you do, it's never going to be a good example.

Given that these look like professional photos, I strongly suspect that the value proposition is not there.

Thanks. I have always liked restoring things, but it probably wouldn’t be the sensible decision here. How much do you think the watch is worth in this condition?

Davidt · Jan 30, 2026

What is the asking price?
Have you checked out the price chart on speedmaster101?

AHW · Jan 30, 2026

Davidt
What is the asking price?
Have you checked out the price chart on speedmaster101?

Around 6000 USD. I had checked, but I was thinking this would grade between a poor-fair, but based on this feedback I am guessing it is a poor condition?

Dan S · Jan 30, 2026

A AHW
Thanks. I have always liked restoring things, but it probably wouldn’t be the sensible decision here. How much do you think the watch is worth in this condition?

Worth … that’s a personal decision. I just know that when I heard the asking price it would need to feel like a major bargain to justify the risk and effort.

hansaboy · Jan 30, 2026

Hi there,
it is always tempting to find a dirty/filthy/damaged 321 Speedy, and thinking that it should be an easy fix....
But regarding this watch, even though you manage to service it, getting it waterproof and start using it,
dont you think that the condition of the watch would bother you?
Even if you get it for a very low price...?
But the sellers asking price is a joke!

The only thing that could be nice would be the dial, but you need much better pictures to assess it.
There are signs of lumeloss, and mold.
Everything else on the watch is actually very low quality = poor.
And some weird spots on the case - corrosion maybe?
Sorry if you get disappointed with my answer (and some might think that I am way of....)!

Skärmavbild 2026-01-30 kl. 18.06.44.webp

Skärmavbild 2026-01-30 kl. 18.06.38.webp

Skärmavbild 2026-01-30 kl. 18.06.26.webp

Davidt · Jan 30, 2026

A AHW
Around 6000 USD. I had checked, but I was thinking this would grade between a poor-fair, but based on this feedback I am guessing it is a poor condition?

With so many unknowns it depends on your appetite for risk.
Personally I see little upside at $6000. That would be the top end of the value of the dial is good and the corrosion to the case is limited to the rear. If not, it’s closer to $4000 imo

AHW · Feb 1, 2026

hansaboy
Hi there,
it is always tempting to find a dirty/filthy/damaged 321 Speedy, and thinking that it should be an easy fix....
But regarding this watch, even though you manage to service it, getting it waterproof and start using it,
dont you think that the condition of the watch would bother you?
Even if you get it for a very low price...?
But the sellers asking price is a joke!

The only thing that could be nice would be the dial, but you need much better pictures to assess it.
There are signs of lumeloss, and mold.
Everything else on the watch is actually very low quality = poor.
And some weird spots on the case - corrosion maybe?
Sorry if you get disappointed with my answer (and some might think that I am way of....)!

Not at all! I appreciate the advice from everyone on here. I am only going to buy one Speedmaster (for the moment) so I want it to be the right one!

I do like restoring things, but it seems like the potential to do so is a lot less with watches than other things. I probably need to accept that my budget at the moment won’t stretch to a good 321 movement watch, unless I am very lucky.

Corrosion/chips around seal

AHW

hen

speedb

Canuck

Dan S

ErichKeane

Canuck

AHW

Davidt

AHW

Archer

Dan S

AHW

Davidt

AHW

Dan S

hansaboy

Davidt

AHW

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