Seiko Caliber 6117B

Brand	Seiko
Caliber Number	6117B
Evolved From	6117A
Base Caliber	6106A
Movement Type	Automatic, self-winding mechanical
Lignes	12”’
Diameter	27mm
Height	5.1mm
Jewels	17
Beat Rate	21,600 vph
Lift Angle	54.5 degrees
Power Reserve	~47 hours
Anti-Shock System	Diashock
Mainspring	401615
Balance Staff	315611
Stem	357611 (World Time) / 354615 (Navigator Timer)
Hand Sizes	1.5mm / .90mm / .20mm
Manual Winding?	No
Crown Location	4:00
Functions	Central hours; central minutes; central sweeping seconds; central GMT hand; date at 3:00
Hacking Seconds?	Yes
Quickset Date?	Yes
Country of Manufacture	Japan
Known Models	Seiko World Time, Seiko Navigator Timer (6117-6419T)

The Seiko caliber 6117B is a vintage automatic dual time GMT movement that was found in the recently re-popularized Navigator Timer watches. This caliber was produced between circa 1968-1975.

Parts Interchangeability:

Most of the parts in the 6117A or 6117B are interchangeable with the base caliber 6106A. A few parts in the 6117X are different based on the model of watch – mostly to accommodate the internal rotating bezel on the World Time (often misspelled as “World Timer”).

Difference between 6117A and 6117B?

There are two variations of the 6117: A and B. They are basically the same movement, however, the B adds a desirable hacking feature.

mwbuss8 posted this comment about the Seiko 6117 on thewatchsiteforums:

“You’re right, parts are tough to source. Be careful with the stem, some sellers out there will advertise as having them for this movement but they lack the feature to rotate the inner bezel. I have the older 6117 6019 world timer. If you have yours serviced and adjusted I’m sure it can be much more accurate than a minute. When I got mine it was in a jar of broken watch parts. The crystal was so bad I could barely read the dial, but by the time I had it out of the jar it was ticking away. over they course of the next 3 days I checked it against an atomic clock and it was only a few seconds off. the 6117 is an AMAZING movement. In regards to movement parts if you ever need them many parts of the entire 6xxx line are shared.”

6117B VS 6118A:

In 1975, Seiko began producing the caliber 6118A which has the same jewel count and Diashock anti-shock protection, but is not a GMT. Therefore, you may see some watches in the wild incorrectly listed as having a 6118, but just remember that the Seiko World Time and Navigator Timer are powered by the 6117A or 6117B.

Additional Images:

Additional Resources:

• List of Seiko calibers