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Posted (edited)

Just about to service foc an AS1700/1 25 jewel automatic movement in a fairly good Tressa watch for my local charity shop.  Balance swings free, time and date set seem ok, auto-wind seems to be working ok but it will not hand wind (cannot turn crown).    I have parts list and some limited tech info (covers only auto-wind, mainspring and date change but not movement).

Any advice will be most appreciated especially location of any Left Hand Threads or anything else out of the norm.

Edited by canthus
more info added
Posted

If the crown can be used to adjust the hands but not wind in the winding position then the mainspring is most likely already fully wound. There will be a fault stopping the watch running & the owner has just wound it fully trying to get it to run. 

I have attached the 1700 parts sheet probably the same as you already have,

AS 1700.pdf

 

 

 

Posted

Beware! On the AS 984 the ratchet wheel is left-hand thread as well as the crown wheel, so this from the same manufacturer may be the same.

Posted

Thanks for your responses.  Will take care with screws on crown and ratchet wheels just in case.  Will take care with letting down/barrel when dis-assembling.  I do already have the pdf, thanks.

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