Teardown + Service: Seiko World Time 6117-6400

This Seiko was sent to me for a service by Simon from Canada. There are two quite unusual features: the red 24 hour hand, and the fact that you can’t manually wind the watch. Only the auto winder winds it. The crown sets the timezone ring when not pulled out, and sets the date when pulled out one stop, and the time when fully pulled out.

Oh dear – looks like someone is spitting on the screen of the timegrapher. Something is wrong here

Auto winder removed

The bronze lever on the left at 10 o’clock is the stopper for the hacking second

The main spring barrel will need a good clean

Watch taken apart – ready for cleaning

Oiling as I go along

This explains the horrible image on the timegrapher

After de-magnetizing, the hairspring is still not quite right. I reshape the dog’s leg a bit, and voila, this should do the trick

Now that’s better. As adjusting the beat error is super-tricky (you can’t reach the collet from the outside, but you have to take out the balance every time), I stop at 0.9 ms. That’s pretty good, and I probably won’t get much closer. The graph looks so much better than at the start, so I’m very happy with this


I put the auto winder back on and close the case with a new gasket – job done.

8 thoughts on “Teardown + Service: Seiko World Time 6117-6400

  1. Hello!
    If I may: why did you have to adjust the collet to fix the beat error? Couldn’t you have done it by adjusting the hairspring end stud support?

    Thank you,

      • Thank you very much for the reply. I’m not trying to test you, I’m just doing some late night reading. A very educating one! 🙂

        • :)) i was looking for this comment. Been there myself, looking back and realizing that i forgot to do this and that on my first watches.Thanks

  2. Nice work. Question on the auto winder. Does the 6117-6400 make use of the
    ‘pawl lever’ for winding? If not, what does it use for auto winding.

    Mike S

  3. This is my favourite watch, although I prefer the white face model, I have two of these one working fine one that I hope to have repaired, fantastic to see one being stripped and brought back looking like new, in my opinion a very underated watch


  4. Pingback: Teardown: Seiko World Time

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