Hi guys, thanks in advance to those who will partecipate in this little analysis.
IMHO A3630 is a perfect watch, surely une of the most charming vintage diver.
I own two A3630:
one is in good conditions with a nice ghost bezel (type A)
the other is close to NOS conditions (type B)


Hands on my tipe A is original Zenith subsea but not correct at all, they should have steel color like the type B, certainly they have been replaced.

In addiction to this there are some differences betwen the watches:
1) on the dial the data window is all black in one (tipe A) and black and white in the other (type B)



2) also bezel are different, the numbers haven’t the same font




numbers are narrower and more defined on type A

I tryed to analize other A3630 (about 15) and I found both type. In only 2 times I found dial type A with case type B.
Cases type A are numbered 723D... while cases type B are numbered 217D...
Surely there where two batches of production.

here another example with a picture taken on web



The question now is: which is the mark 1 and which is the mark 2?
I suppose type A is mark 1 e type B is mark 2 but I have no confidence on numbering order in Zenith.
We could have the answer asking for an exctract to zenith of both the examples (I will do), but now LeLocle is closed...
So, A3630 lovers please share your opinion and your best photos of your beasts


Mine say hello!

 

The movements will tell. Cal. 2542 is mk1 ('68-'69 range). The 2552 is mk2. (70-72 range).

 

I am a truly lover of A3630, but it is not in my collection (yet). Reading here I learned a lot, although I am far away of an expert.

probably movement will tell you the truth, as @bristnj said.

 

Decent example on eBAY:

https://www.ebay.com/itm/362950151980Purchases made through these links may earn this site a commission from the eBay Partner Network

 

Mine is a 1st execution (1968) with cal. 2542.

Some other very good info on this thread:

https://omegaforums.net/threads/zenith-a3630-zenith-divers-at-large.56148/page-4#post-1381596

 

That example on eBay has dial reprinted (look at the write AUTOMATIC and at the number on the dial), bracelet is 18 mm instead of 20 mm

 

your is one of the best piece I’ve seen, if I’m right the number on your the case is 217D...

 

Good catch - only looked via my phone.

 

Here I share the census I made:

SERIAL NUMBER CASE DIAL
216D... TYPE B TYPE A
723D... TYPE A TYPE A
217D... TYPE B TYPE B
217D... TYPE B TYPE B
723D... TYPE A TYPE A
217D... TYPE B TYPE B
216D... TYPE B TYPE B
? TYPE B TYPE B
217D... TYPE B TYPE B
217D... TYPE B TYPE B
723D... TYPE A TYPE A
217D... TYPE B TYPE B

COMBO NR
CASE A/DIAL A 3
CASE B/DIAL B 7
CASE B/DIAL A 2


So what we know is that there were 2 kind of cases (with little difference on font of numbers on the bezel) and 2 kind of dial (all black window and black&White window), because of all black windows compares with both cases I assume they was made by 2 different productive lines but in the same time.
According to @bristnj’s 2542 with type B case, now I presume type B was the first batch and type A the second.

According to the case number I found I presume a total production of about 1000 max 1500 pieces.


With the end of lockdown I will verify the movement of my watches (I need my watchmaker) and I will ask the extract to identify the right year of production, I will also try to get from zenith the number and the years of production

 

I just checked, my case is 216D5XX

 

Thank you for this analisys, it's a ref that I love and sooner or later I'll have the pleasure to own an example of it.

 

TypeB one of the lower number I found