Part 1. Diving in the 70’s
When I thought for the first time of the retrospective you are about to read, I had no idea of what surprises this would lead me to. It was supposed to be an easy and quick job. In fact, it took me months to collect watches, pictures, advertising in order to have the most complete as possible overview of this amazing saga.
But my curiosity and my effort were paid in return and I’m very pleased to offer you the results of my searches. Despite the rigor that I have tried to show, it is possible there are still missing or inaccurate information. Don’t hesitate to tell me in comment.
Jean MÜLLER, the YEMA Navygraf’s father

Jean MÜLLER, has been in charge of Yema watches design from 1975 to 1982. During this decade, he designed stunning watches that contributed to build the brand notoriety. They make today the happiness of the YEMA enthusiasts. Jean Müller has had in particular some strokes of genius to conceive on his drawing board middle cases with out of the common shapes. I think specially of the chronograph middle case that equipped the highly coveted Flygraf 91.003.6, the Yachtingraf “Digital” 93.003.6 (also unofficially called Régate), or the Rallygraf, known under the unofficial name of “Brown Sugar”. A total of 6 or 7 chronographs have been manufactured with this case, among which, also.

And Jean Müller created the YEMA Navygraf. I have been able to get in touch with him, and had the privilege of long interview in 2019. You can read it on Le Club Yema web site (in French). A good way to know better this prolific watch designer.
The YEMA Navygraf “I”

The Navygraf “I” appeared in the YEMA catalog during the late 70’s. This watch is famous for its yellow hands and its indices looking like exclamation marks. I call it “one” despite there has never been any number for this watch. Its original name is just “Navygraf”, with the catalog reference 55.003.6 AS. It has in common with the chronographs mentioned above the same beveled edges on the right side of the middle case. This watch was equipped with a France Ebauche FE 4611 movement (quickset date).

This Navygraf “I” has also been produced later with a modern YEMA logo. Its little sister, the Super Navygraf electronic is quite interesting, for it is brought to live by an electro mecanic caliber ESA 9158 (quickset date).

There has been a second variation of this model. Same case, same movement. The dial was only printed with the Electronic HF inscription, without mentioning the “Navygraf family”. The “HF” mention could stand, without any certainty, for “High Frequency”. The production must have been less important because we meet it rather rarely.

In 2022, Yema reissues revives the Navygraf I with a bronze special edition to celebrate the 50th anniversary of the French Navy Submarine forces. Read te review here.

The YEMA Navygraf II
The YEMA Navygraf II, is one of the most interesting dive watches of the French watchmaking brand, and, clearly, my favorite.

The Yema Navygraf II have all in common a very characteristic case, with a flat mineral glass, square lugs, a big screwed down crown, protected by a massive square crown guard. Regarding he information Jean Müller gave to me, this case was probably produced by Schneider, a French company in Besançon. The “unremovable” bidirectional bezel is fixed by two holding plates screwed into the case. You would be able to recognize its unmistakable design among thousands. The fluidity of the rotation is ensured by a teflon (more specifically a self-lubricating polytetrafluoroethylene) ring. We will see a little later that two patents were in fact registered for the NAVYGRAF II bezel system. The dial is protected by a flat mineral glass. The watch is 990 feet waterproof.
- Diameter: 38mm without crown, 43mm with crown
- Lug to lug: 45mm
- Strap width: 19mm
- Thickness: 13,5mm
Compared with the famous YEMA Superman, the Navygraf II brings a significant enhancement: the diver doesn’t have to unscrew the crown in order to set his watch bezel to monitor his dive time. The bezel setting can be adjusted under the water. A real advantage for the user.
The Navygraf II | 961 122
The 961 122 is the first Navygraf II ever produced. On 1976, November 3rd YEMA filed a patent under the title of “Watch provided with an external rotating bezel”. The patent has been registered under the reference 2.370.307

All the watches produced under this reference have the following common characteristics:
- There is no blocking system for the bezel, free to turn in any direction despite the holding plates and the friction of the teflon ring. Obviously not very reliable for a diving session.
- The plates fixing screws have flat black heads. Most often, the black surface of the screw heads has been polished by the rubbing, but the black color is still present on the flanks.
- The screwed stainless steel caseback is engraved with the YEMA’s crest. the engraving is shallow. It is often partially erased.

The 961 122 reference has been equipped with an automatic France Ebauche FE 4611 movement (quickset date) or a quartz ESA movement. The models that I had in hand were indifferently equipped with ESA Y2 9362 or ESA 536 121 (late version of the 9362). Theoretically, both these movements are “day date” calibers. As the Navygraf II has a single date aperture, I assume that the original movement could have been the ESA 9461 (date), maybe changed during a servicing operation by removing the day disk. But anyway, good to know to restore your old quartz Navygraf II abandoned in a drawer.


The automatic models have in common a lollipop second hands. The dial is brushed, grey or black, offering various color density depending on the light angle. The YEMA logo, printed on the dial, is my favorite one: “Y” calligraphy within a circle. Same as the today YEMA collection.
The oxidation phenomenon combined with the sun light exposure sometimes lead the dial color to turn brown, as on my own Navygraf II, making the watch unique.

The quartz models have a mate black dial and a straight orange second hand, like this one. I only know one exception, which is presented just after.

There also exists a dial with a white quartz inscription, with a modern YEMA logo, as shown below. Note that I’m not sure about the authenticity of the second hand, because of the lack of the usual counter weight.

The mysterious propeller
This is an unusual version of the Navygraf II, with a modern YEMA logo, a straight beige second hand and a mysterious propeller pictogram at 06:00. This pictogram also exists on some YEMA Superman. I have done a lot of research on this subject, without success. I assume that these dials were specially printed for a diving club or something like that. In case you recognize it and know where it comes from, please let me know!

The black YEMA Navygraf II ref 961 122
The black Navygraf II 961 122 is a true rarity. It has black plates, black steel strap. However the case is in the same “raw steel” as the other models. It is not black. Probably for production costs reasons.

On the above picture, the screws should probably be black. On the picture below, the screws should probably have flat heads. But only “should”. It is very difficult to be 100% sure regarding the Yema documentation confusions.

Due to confusions in the YEMA documentations, I have thought for long that this black Navygraf reference was 25.025.6 AD. Look at this April 1977 catalog extract. But thanks to pictures D. Franzoni was kind enough to share with me, I am now convinced that both above watches are 961.122. Thus a question remains: did the 25.025.6 AD black with a locking rod ever existed?

The Navygraf II | 55.025.6
The queen of the Navygraph II is born in 1977. Only one year after its elder. Technically speaking, it is not the most accomplished of the Navygraf saga, as we will see later. But the 55.025.6 reference is without any doubt the most emblematic watch of the whole collection.

This model brings a strong enhancement to the previous thanks to a new feature: a bezel locking rod that allows a much more secured usage of the watch. This improvement has been the subject of a second patent application ref 2.402.898, registered on 1977, September 8th under the title Device for locking the rotating bezel of a watch.

If this system is a real enhancement, one can’t say the same about the BTR head of the screws that now fix the bezel holding plates. First, these protuberant screw heads proved to be sensitive to chocks that often occurs while diving. This is why you often find this watch with damaged screw heads, missing screws, or even worse incompatible screws that enlarged the original holes. A detail you really have to pay attention to when buying this watch. These screw heads are black, but often polished by the usage. However, despite the reliability issue, these new screws give the watch an unmistakable design.
I know three dials for this watch in its automatic version: black dial with a circled “y”, brushed grey or mat black dial with a modern logo.


Nope… I don’t have any picture of the third one. All these watches have a very simple caseback, without any logo. It is engraved with the reference 55.025.6 and a without any surprise circular text at the edge “All Stainless steel Water resistant Modèle déposé”.
The Navygraf II | 25.025.6
The YEMA Navygraf 25.025.6 is exactly the same watch as the 55.025.6 excepted a straight second hand and a quartz movement ESA Y2 9362. You may find this reference with a modern « Y » in hollow, as presented on the picture here after, or with a circled « little y » and a beige second hand. The caseback is engraved with a circular mention “All stainless steel Water resistant Modèle déposé Quartz” and the 25.025.6 reference in the center. Unfortunately I haven’t had the chance to catch one. Both pictures below have been collected on the web.
This Navygraf was presented in the YEMA catalogs under the reference 25.025.6 AC and 25.025.6 AD (black).

These watches give to me a good opportunity to explain the “meaning” of the references in the collection catalog at that time. They were determined according to 3 criteria:
- the two first figures are for the movement. Regarding the Yema Navygraf II, 25 is the quartz reference, 55 is the automatic reference;
- the three following figures are the case reference. For the Navygraf, its 025. Remember the 003 reference for the Chronographs I mentioned at the beginning of this article;
- the two letters are the dial reference.
If you are familiar with the vintage YEMA universe, you already know that the case reference is sometimes the same as the commercial reference. And sometimes not. Even with the right sources and explanations, it is often difficult to find your way.
The YEMA Navygraf II, a military watch?
I have read here and there that the Navygraf II was made especially for the French army. As I have never seen formal documents nor heard or read substantiated information from former Yema employees I believe that this is not the case. However, its perfectly true that its commercial version was judged reliable enough to be part of the equipment of some military divers. Here is the story of one of these models, a YEMA Navygraf 55.025.6 CT automatic, as told to me by its owner, whose father was a member of an elite unit at that time. His initials, “LJB”, I will only share for the obvious sake of discretion.
As a preamble, you will notice the callygraphic inscription of the name “Navygraf” on the dial, same as the Navygraf I, under the modern logo. There is no specific military inscription, such as service date, on the caseback. This watch is exceptionally rare. I asked Jean Müller about it. Unfortunately, he could not find any information in his memory. You will also have immediately noticed the unusual bezel.

“This watch was given to my father in Corsica by the “boss” of the military divers of the DGSE Action Service (edit: DGSE stands for Direction Générale de la Sécurité Extérieure i.e. French Secret Services) at the time. Given the units involved, the context of the time (Cold War, end of the Algerian War, …) and the missions carried out by these units, you will understand that you will not have other information.
So yes, this watch has been used in special forces units and in intelligence. No idea about the more “conventional” units of the Army. (…) The bezel insert has always been this black one. According to my father, this may be due to the fact that some of the equipment used by these units, and in this case the watch, may have a “civilian” base but modifications are made to it to make it more suitable for their particular use. (…)
The watch was then switched for a YEMA Navy (edit: we’ll see this watch later). When diving, it happened that the security of the Navygraf moved and therefore the rotating bezel unlocked. The rotating mechanism being smooth, the bezel moved too easily. It was therefore problematic to know the duration of the dive, the decompression stages to be made and so on. On the Navy, the bezel rotates on an apparently notched mechanism. The rotation is therefore less easy in case the locking rod is removed”. Courtesy LJB
2021 October 24th update. The Navygraf II saga is truly a never ending story… A few months after this article publication, my eye was drown to a Navygraf II picture on the “Yema Watches Owner” facebook page. And here is how I discovered the quartz version of the very rare “Callygraphic Navygraf II” dial! I thank the owner for sending me the picture below.

The YEMA Navygraf II mood
As often at that time, it happened that dial manufacturers provided different brands with… the same dial. These watches have something familiar with our Navygraf II, don’t they?

Commercial break!
Here is a selection of ads featuring the YEMA Navygraf II.
I do like the old advertising. Most often we don’t read them with attention. But they are full of information. For example, you will notice that the 961.122 reference is never mentioned. What does that mean? Has the 961 122 ever been a catalog reference? Probably not. You will also notice that the reference doesn’t change even when the logo is different. Not easy for the YEMA enthusiast to find his way in this maze. Take time to look and read the captions. I promise you a few surprises.
The Navygraf II… the top of range of the YEMA diving watches? Yes, sir!

The Navygraf II on this ad’ is most probably a 25.025.6 AC. Modern Logo, locking rod. Very interesting detail: the Navygraf II is 25% more expensive than the Superman (725 F vs 580 F)! It means the YEMA Navygraf II was, at that time, the top of range of the brand diving watches! The gap is probably probably due to the higher machining cost of the Navygraf case, and probably also because the investments cost for the Superman were amortized for long at that time.
Black… or not black?!

… But what? The 25.025.6 AD reference is supposed to be for a black case, isn’t it? (Look to the following ad if any doubt). Notice the mix of circled and modern logo, and the 961 122 case (no locking rod). Confusion, confusion…
The quartz revolution

Three interesting details on the above ads: (1) the quartz models 25.025.6 are more expensive than the automatic model 55.025.6. Quartz 795 Frs Automatic 600 Frs. Welcome in the quartz revolution! (2) The black quartz model is less expensive that the “all steel” one. Regarding the additional treatment to lead to a black watch I expected the contrary… (3) only circled logos and 961 122 cases (no locking rod) on these ads. The price evolution suggest the publications are older than the previous ones. However the watches are more expensive… (4) I have seen this same watch in a professional magazine under the commercial ref 270256 BR. (5) I’m definitively lost…

YEMA, an international brand
In 1958, YEMA was awarded the Oscar for Export by Edgard Pinet, Minister of Finance. YEMA SA then became YEMA International. For the French brand, the international market has always been a lever for development. It is quite surprising to find so few advertisements addressed to foreign customers. However, here are two examples of advertising showing the Navygraf II. In Portuguese or in English. You to choose!


The YEMA Navygraf II, best Yema ambassador?
I found servicing paper bags on which a YEMA Navygraf II was printed. Scale 1:1. I don’t know whether this watch has been the best Yema ambassador. But obviously not the worst… A real symbol to demonstrate the Yema watches’ reliability.

My favorite...
Put a pinch of 961 122 (reference & logo on the caseback), add a locking rod, mix with two different straps, stir pouring the references 55.025.6 and 25.025.6 in the text and you’ve got… a very heteroclite instruction manual! Dish to serve before the ink is dry.

Now read Part 2. Diving in the 80’s… and a little later.
Don’t forget to subscribe to my Instagram Jerry_watches to be informed of next publications.
Hope to see you soon on Clock Me Tender. Take care!
Jerry









Hello, can you please tell me what year is that black & white advertisement that is titled “A competition brain. Navygraf II or Navygraf 2? Price 725 Frs ©Archives YEMA” … thank you very much !
Hello Roger. Thank you for your message. Unfortunately I don’t know the exact date of his advertising. However, considering what I know about Yema history, I would say it has been printed at the very end of the 70’s or early years of the 80’s. So let’s say between 1979 or and 1980.
Thank you !!!!!
-Roger
Mr Jerry bonjour,
Je suis tombé amoureux de ma plongeuse après avoir lu “La saga des YEMA” .
voila la petite histoire; en 1976 nous partons au Cameroun pour plusieurs belles années de plongées .
En 1977,ma femme m’offre une NAVIGRAF II 961122 AUTOMATIC”Super belle bête”
En 1980 la montre coule suite à la rupture du bracelet d’origine (montre retrouvée quelques mois plus tard par mon copain de plongée de l’époque.) Ouf !
De retour en France ,je porte ma plongeuse (qui ne plonge plus) tous les jours jusqu’au 08/2009 où mon bracelet inox de remplacement à la malheureuse idée de faire masse entre le plus de la batterie 24 volts et le châssis de ma jeep lors de travaux de mécanique.
Bracelet fondu, poignet grillé, montre dans le tiroir depuis ce jour.
Je suis très attaché à cette plongeuse qui a bien vécue et aurait besoin d’un” rafraichissement”. Elle fonctionne encore .
Suite à une révision en 2006,le verre, la couronne ,les vis de fixation des plaques ont été remplacés
,mais ne sont pas identiques à l’origine (verre moins épais),couronne plus petite,…..
J’aimerais faire remplacer le verre, la couronne , relumer les aiguilles et remplacer la lunette (voir état sur photo)
Je me permets de vous demander où je pourrais m’adresser pour la remettre en état.
Merci de m’avoir lu.
(Je n’ai pas trouvé un lien pour vous mettre des photos)
Bonjour Monsieur.
Merci pour votre message ! Je suis ravi que mon article ait réveillé en vous l’envie de donner une seconde vie à votre Navygraf II. Ce type d’histoire qui donne à une montre un caractère unique est toujours extrêmement sympathique à lire (même si cela l’est beaucoup moins pour le propriétaire…). Je vous propose de poursuivre notre échange par e-Mail, ce sera plus facile. J’ai sans doute quelques pistes à vous proposer. Vous pouvez m’écrire et m’adresser vos photos à l’adresse clockmetender@gmail.com. Cordialement, Jerry.
Intéressant article.
J’ai une Navigraf, avec un I à la place du Y et un mécanisme FE8121 (orloger dixit).
Vous auriez une idée du pourquoi de ce I ?
Merci pour votre message ! Quelle référence avez-vous au dos de votre montre ? R4 043 6 ?