Citizen Diver OR-O B52806 or 62-5370 are, more or less, the same model. Both of them are difficult to find, no matter the condition, to find a NOS one… almost impossible. The 62-5370 is made for domestic market and the B52806 for export and has its own awesome engraved case back. So, they have different case backs, different hands sets and dial codes but they share some of these features sometimes (variants or marriage?). The second hand tip received a luminous ball for better visibility for the export model. The 62-5370 can be found with a simple second hand. The only obvious thing that is constantly different is the case back. The movement is Citizen cal. 5470 for 62-5370 and 5430 for B52806. I don’t see any other difference between these two calibres other than the swinging rotor.
I had to have both of them even though in the first place I got only the NOS export model (because of the beautiful case back). Both of them are marked water proof 150 M in a period when the term Parawater was about to… unfortunately disappear. This water resistance is possible due to thick mineral crystal, screw in crown and case back. They ware made in ’69-’70 but the exact period is impossible to determine for the export model because it has no serial no. The 62-5370, on the other hand, has a serial engraved and the manufacturing date can easily be seen.
So… one model with variants or two distinct models? The debate might still be on but as far as I am concerned I will consider them variants of the same model and… have them both!
Read about the complete 150m Citizen diver collection HERE.
Vintage Citizen Watches 
Pingback: Complete Vintage Citizen 150m Divers | Vintage Citizen Watches
Pingback: Citizen 150 m, réf. 52-0110 – Chronographes
I have one from 1969 with a non screw-down crown. Have you ever heard about this !
LikeLike
If the crown is broken, it could be non screw. 😉
LikeLike
Hi
The outside crown is damaged but the mechanism is a non screw, confirmed by the watchmaker. This is why it is interesting. The crown itself is a genuine Citizen, but with a non screw configuration. You cannot replace it by a screw in Citizen crown.
LikeLike
Than, sorry, it is not original. Maybe a marriage with original parts.
LikeLike
That’s where it is interesting. The crown holder is original and its design is non screw in. Also, due to its shape and diameter it can only fit a challenge diver case… it doesn’t come from another Citizen … and the crown is genuine Citizen Challenge Diver (even exists in Citizen spare part catalog as a non screw down)….
LikeLike
I have just received a very original B52806, that I found on the Jauce Japan site. I comes with a Citizen marked rubber strap, a plain (not lollypop) second hand and a NON Screw-down crown. This crown is the 506-502 model crown (and NOT the 506-5021 screw-down one).
This model appears to have been the competitor to the Seiko’s 6105-8000 diver; and spans an identical period. I suggest that the early model B52806 were initially, like the 6105 slim Willard, push-down crowns with stem seals; and that the early model also had the straight second hand. I further suggest that the lollypop second hand along with the screw-down crown appeared towards the end of the production run. This would indicate that the switch from a push-in to a screw-down crown was introduced during these two Citizen models ( the B52806 and the 62-5370’s) production run, whereas Seiko side-tracked in 1972 with the locking crown before following suit?
LikeLike
I checked two B52806 and one 62-5370today in a vintage watch fair in Tokyo and none of them had a screw down crown. So it seems these models were made with 2 types of crown. I bought one so can send pics of needed
LikeLike
I know them, had them, serviced them… still… not original parts. They should be screw down crowns. Non screw down are replacement.
LikeLike
I know them, have 3 (2 Japan/1 Australia), didn’t service them but open them too. How would you explain that all 3 have the same non screw crown and the tube (inside the case is not accepting any crown from any other 150m because it is not a screw down compatible tube). Also the inner water protection inner mechanism looks similar as a Super Jet Parawater 150m. And other than the 3 I have, I checked one more here and same thing.
LikeLiked by 1 person
I totally agree with Serge Panczuk, My recent purchase; ultra original, untampered, near mint condition from Japan and on a period (original?) citizen rubber strap; has a non screw-down crown. Once removed the stem seal area is that of a normal push-down stem seal crown, a la 6105 slim Willard. we appear to have an evolution going on at Citizen on this model and over this production run?
LikeLike
I have my dad’s stainless steel 150M diver from late 1960’s / early 1970. On case back, it has ref. 62-5370, but case # is different than most others that I’m finding online. Case is “4-540565 Y” and serial number is “0072279 8.” Caseback also says “Parawater,” not “waterproof” (though the black dial says “waterproof” at 6 o’clock position, above “150M.”
I haven’t seen similar examples with casebacks that match what I have. From what I can tell from the serial number starting with “007” that it may have been been in July 1970.
Cyrstal is in great shape and all original parts and I’m just trying to see if this is a standard “62-5370” or is it something unique?
LikeLiked by 1 person
It could also mean it might be made out of parts. Upload a few pics if you can.
LikeLike
<
div>
<
div dir=”ltr”>
<
blockquote type=”cite”>
LikeLike
Hi, I wonder if this thread is still a live one? Having acquired a 62-6198, and falling head over heals for it I´m now thinking of a 5370 / B52806. My worry is parts and especially things like crowns, stems and crystal rings, Does anyone have parts numbers for these movements. I think I need to get these things before I think of splashing out (I needed a crown for my 62-6198 and consider myself possibly lucky to have sourced one, the stem was also the last that I´ve seen on offer as well).
LikeLike
Hi, I wonder if this thread is still a live one? Having acquired a 62-6198, and falling head over heals for it I´m now thinking of a 5370 / B52806. My worry is parts and especially things like crowns, stems and crystal rings, Does anyone have parts numbers for these movements. I think I need to get these things before I think of splashing out (I needed a crown for my 62-6198 and consider myself possibly lucky to have sourced one, the stem was also the last that I´ve seen on offer as well).
LikeLike
I just BIT the bullet so to speak; Found a VGC almost mint B52806 on Jauce Japan (has a few scratches but excellent internally and back seal area) and just HAD to make a bid. I ended up winning. I will post more shortly….
LikeLike
Congrats! Awesome watch!
LikeLike