Jump to content
  • 0

Seiko 66-9990 access to movement


I've got this 1963 Seiko 66. Not worked on one of these before. Can anyone advise how I get the movement out please?

I have removed the bezel and it started to run, probably because the bent second hand was stuck, which is promising.

It doesn't look like the back comes off but I'm not sure?  Does the crown and stem pull out or unscrew?

Any help appreciated.






Link to post
Share on other sites

3 answers to this question

Recommended Posts

  • 0

If you haven't work on a 66 previously, remember when disassembling it that there's a tiny washer between the 4th wheel and the center wheel bridge. It can be easily forgotten and get lost in the ultrasonic or in the cleaning process.



Edited by aac58
  • Like 1
Link to post
Share on other sites

  • Recently Browsing

    No registered users viewing this page.

  • Topics

  • Posts

    • 3:29  Oooooohhh that went silky smoothly, I bet nobody else saw that coming. 😆  I remember doing something similar with an old Hornby clockwork locomotive that no longer worked, when I was a kid (showing my age again). I undid the four screws holding the thing together and there was a very similar explosion of uncoiling steel with the addition of a few airborne cogs, and a very confused me sitting thinking bloody hell how did they manage to get all that spring in there, and how the heck am I going to get all the bits back in.   Speaking of which, how the heck is he hoping to get it all back in? Superglue and a hammer? AndyHull grabs the popcorn and starts looking for the follow up video.
    • I also made my account on CousinsUK but cant find Seiko Complete  balance can u provide me any links. Thanks.
    • Will this Fit ? I came across this site while searching for parts this looks similar but belongs to NH36.
    • Hi Tudor, Thanks a lot for your advise. I considered it as the best solution. Later I discovered that manufacturer did it with an hexagonal 0,5 mm stake, but seems it does not work as expected,  as could be seen in the photos of same watch I could find on Internet, almost all are out of "synchrony", so I have my doubts and, any case, I don't have any stake to try it. The pinion diameter is around 0,5 mm diameter at the junction, trying to drive a 10 mm wheel, so the relative torque is so huge that it overcome the manufacturers expectations (I wonder who calculated it, maybe a floating comma fooled him). (Tried to attach a better photo but the page do not allow me to do. I'll do later if possible) As I suppose there may be some shoulder just below the wheel to support it, I though a fluid adhesive may penetrate it enough to increase the adhered surfaces and hence increase it's torque performance. As I have no experience with such kind of junction I'm trying to test different adhesives that can be eliminated to check different makes if not successful.  After much thinking and searching I think shellac may deserve a try, diluted it may penetrate everywhere and it could be easily cleaned. I'll post the outcome when I could do it.  Again thanks for your help
  • Create New...