Seiko 6138-0040

[LonglineOjoe]

Good Morning from Long Island NY!  

I'm in the final stretch putting together this watch (that I actually stripped down, cleaned ultrasonically and oiled!) and I'm about to attach the hands as I received my VTA holder early:).  As I was winding through 24hrs I noticed that while the date changed crisply, the day was a bit sloppy, not precisely in the window.  I removed the dial and have been fiddling with it, checking the spring and the gear alignment but it still seems too free, able to spin haphazardly.  Anyone know what I'm missing?

[Ishima]

Oh that's a nice movement if i'm looking at the correct service sheet. To be honest i only have limited experience in this area and that with lower end seiko movements, however they have similar calendar works. 

The most obvious thing is wear or damage on the day jumper (part 873610) might not have the correct tension to hold it.
Failing that i've often had to play about with how firmly pressed down the day ring c clip is. (if indeed it is pressed down and not in a groove) 

Is there any difference in how the calendar behaves when changing day/date vs turning the hands to advance the calender?


 

[LonglineOjoe]

Not really, still a little too loose in the action.  I did think about that C ring but its as tight as I can get it safely.  I'll try swapping out the jumper, see if that helps.  Thanks!