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Seiko 5126A



Can someone please explain to me how on earth do i unwind this Seiko 5126A movement prior to reassembly? (Picture attached).

No manual winding as far as I could find and the winding screw on top of the bridge is not counterturning automatically when I push back the click and basically nothing happens. I can unscrew it but this just releases the screw.

I'll mention that I did experimented with this movement (it's my watch) and first time accidently removed the bridge with power still left. No visible harm was found and after reassembly (hopefully a proper one) everything seemed in order (except for the oiling and cleaning which I haven't yet performed and is due now).




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Perhaps push the crown wheel teeth with a wood or plastic stick to release the click and then hold the click off while you ease it down with the wood/plastic?

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Hi  If you are unable to disengage the click using the stem, then the method as suggested by Tudor will work as long as you are careful another method is to remove the balance and hold the train wheels whilst removing the fork/pallet an controlling the run down of the watch, this takes Great care.

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13 minutes ago, JohnR725 said:

What kind of timekeeping Does this watch have? The reason I ask is the regulator isn't quite were it is supposed to be And neither is the stud?

Finding technical or service information for this watch is challenging did find you a parts list.

Seiko_5126A.pdf 807.83 kB · 0 downloads 7310_Seiko 5106A - Parts List.pdf 1 MB · 1 download

Thanks for the additional info! 


As far as the regulator, you are probably right. Haven't had it regulated yet and just fiddled with it (and i'm still short of a timegrapher but that' a different story). The movement still needs to be cleaned and lubricated as mentioned so even if i had a reading it would probably be a bad one, fitting a dirty and gummed up movement.

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8 hours ago, watchweasol said:

Hi  If you are unable to disengage the click using the stem, then the method as suggested by Tudor will work as long as you are careful another method is to remove the balance and hold the train wheels whilst removing the fork/pallet an controlling the run down of the watch, this takes Great care.

So a quick update: 

Did what watchweasol suggested - blocked the escape wheel gently with tweezers (maybe should have held the third wheel instead but wanted to stay close), removed the pallet bridge and fork and then with my brass tweezers and third wheel slowly ran it down. 

Worked better than expected.

Thanks again!


Edited by Rafael
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