The Card
There is no information as to why Rolex may have produced these watches. Some have
speculated that they were a test prior to the new 116710 GMT IIC, but this would
certainly not seem correct given the late production. Some have also speculated
that Rolex had more 16710 cases than older 3185 movements to match, but people also
doubt Rolex has run short on the 3185. The warranty card on the left indicates an N for Noir (Black bezel). The Red/Black bezels have an "A" designation and Red/Blue has a "B" designation on the card (image at bottom of the page) (click for larger image)
The Case
This is certainly a rare anomaly of Rolex production. All four are M serials two came with black bezel and two with Pepsi bezel. There is no notation on the paperwork or otherwise to indicate they have the 3186—-the only way to determine the type of movement is to open the watch to confirm. Another possible example in Finland (with Z serial) has been mentioned in a previous post on the watch forums. You will also notice that the pictured watch has an unusual dial—-the "II" of "GMT-Master II" is in "non-roman," or "stick" font. The stick II on GMT's have been bantered about regarding the GMT's collectability and possible dial printing error. There are many GMTII's with the same dial, presumably without the 3186. Interestingly all four of the noted 3186 GMT II’s have this dial variant. More images if the Stick Font II are listed below.
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Caseback Removed
There was thought that one reason Rolex increased the case thickness for the new 116710 was to accommodate an increased height of the 3186 calibre. But as as the photos show, the 3186 fits nicely in the older case.
(click for larger image)
This picture from another source shows the Parachrome hairspring, but look closely, the baseplate appears to show 3185.
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It's definately a 3186
The 3186 on the movement definately insures the movement number.
(click for larger image)
... And another 3186
Charles Newgass on Timezone purchased a late series M3XXXXXX Coke bezeled 16710. He indicated that when unscrewing the crown and changed the 24 hour hand, none of the hands wiggled, a tell-tale sign between a 3185 and 3186 movement as the wheel train is closer together on a 3186.
Charles had the back removed and found a 3186 movment.
(click for larger image; photo used with permission)
Distance to the Crown
The thickness between the crown and the movement is definately less than the upgraded 116710 case. This is definately a traditional 16710 case.
(click for larger image)
Tahoeblue definately blew this urban myth. Our thanks to his fortitude on correcting what many had thought was sheer nonsense. With this discovery, there is a good chance that M-series Explorer II's might have the same 3186 movement.
-Pictures and text re-posted with permission from Tahoeblue.
3186 Movement in 16710Z Series
Found in Hong Kong
Andy, known on many Rolex boards as RolexLover, uncovered a Z series 16710 in Hong Kong. Andy bought this watch from one of the Rolex's AD in Hong Kong around summer 2007. It had just been checked and vertified by the Hong Kong RSC in March 2008.
(click for larger image)
Andy has searched in the Internet and has found at least five more in US, one in Finland, one in Germany, one in Taiwan and two in Japan. It appears that these GMT 16710's have serial numbers ranging from Z9xxxxx to M2xxxxx and have the tell-tale stick-figured II in the GMT Master II label on the watch face and the " - " between the "GMT" and "Master" is a little off-center. Most of the late Z and M series 16710's have appeared to be shipped to Europe and US, with very very limited to Asia and Hong Kong. Andy writes of his discovery here. A 500k .pdf of the listing is posted here.
Below are more images of Andy's Watch. Click on an image for a larger picture. |
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-Pictures and text re-posted with permission from RolexLover
More 16710 Anomalies
Another Dial Face Discovered
wchiang on TimeZone had the opportunity to handle multiple M-serial 16710 with calibre 3186 and discovered another type of dial face. The infamous "stick II" font on the dial (as opposed to the traditional "roman II") has already been documented, but there is also a 3rd type of font that looks more like a rectangle.
The rectangular II dial is very interesting; it is not either "old" or "new". It is very random. While it was found on a M23XXXX with 3186, it was also found on a Z77XXXX with 3185.
wchiang discovered the following:
Commonly seen on older 16710 - Roman II
Z77XXXX - 3185 Rectangular II
Z96XXXX - 3186 Stick II
M23XXXX - 3186 Stick II
M23XXXX - 3186 Rectangular II
M30XXXX - 3186 Stick II
M30XXXX - 3186 Stick II
M36XXXX - 3186 Stick II
MXXXXXX - 3186 Stick II reported by Tahoeblue (above)
There is no real pattern for the rectangular II to show up and apparently very random on which calibres, 3185 or 3186. Besides the difference in numeral "II" wchiang also observed the following several differences on the two different dials:
1. All other fonts are slightly different.
2. "-" is shifted to one side on Rectangular II.
3. "Oyster Perpetual Date" has larger spacing in between on Rectangular II.
4. "Swiss Made" is smaller on Rectangular II.
5. The rim on hour markers are thicker on Stick II.
While the 16710 + 3186 is very rare, Rolex threw the rectangular II into the mix to make this whole thing more interesting.
Below are pictures of various 16170 anomalies. Click on an image for a larger picture. |
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16710A and 16710B
More Dial Face Anomalies
ChamptheKid on Timezone posted more images of 16710 with known 3186 movements.
Below are pictures of various 16170 anomalies. Click on an image for a larger picture. |
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3186 Movement in Explorer II
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Fr. John Shinall sent me images of his M153### series Explorer II that he and a friend purchased. It is becoming obvious that the late series Explorer II's are fitted with the 3186 movement. One good sign is whether the Rolex-Rolex-Rolex engraved rehaut, or commonly referred to as the RBR or "Rolex Branded Rehaut" is visable on the watch face. The rehaut is frequently mistaken for the chapter ring, but this is incorrect. The difference between the chapter ring and the Rehaut is described here.
(click for larger images)
My 16710A w/3186
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After passively looking for a blue-black 16710 with a 3186 movement, I found a 16710A M-series at Fourtane Jewelers, a Rolex AD located in Carmel, California and the same AD whose images are at the top of the page. I worked with Joshua Bonifas who is well versed in everything Rolex, including vintage. His store has quite a collection of classic vintage Rolex, including double-red Submariners and SeaDwellers. Josh shared that some of the pieces and store fixtures in the Anitiquorum Rolex auction were from his stock.
I fitted my 16710A with a sapphire caseback in order to watch the Parachrom Blu hairspring. Changing the 24hour hand was smooth, just like the 3186 movement in my Rolex 116710. These 3186'ed 16710 watches have a A and B designation. "A" is for a Red-Black bezel and "B" is for Blue-Red.
The image above shows the watch face with the Arabic II in the watch face, and the bottom pictures show the Parachrom Blu hairspring and balance through the sapphire caseback.
This watch offers a classic, tool watch case, with forward thinking, modernized, movement. In my mind, this watch offers both classic and current Rolex style and technology.
(click for larger images)
The Wiggle Test
One method for discerning a 3185 with the 3186 movement is by the "Wiggle Test". Rolex moved the wheels in the gear train closer together in order to keep the hand movement to a minimum when setting the watch. On 3185 movements, all the hands rock when setting the hour hand, whereas on the 3186, the hands do not rock when turning the both the hour or minute hand. When a 3185 and 3186 movment are side-by-side, it is a discernable difference. If you are at and Authorized Dealer not sure whether there is a 3186 movement inside a traditional GMT case, try to find a 116710 (GMT-C) at an AD and perform a side-by-side comparison.
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| Click image for YouTube video on setting the hour hand on a known 3186 movement. | Click image for a YouTube GMTII 3185 review. During the demonstration of setting the hour hand at the end of the video, it is very apparent the amount of the hands rocking. |
