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  1. Deaney Aug 14, 2017

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    Hi I'm new to the forum so please bear with me.

    I have just started servicing an Omega Seamaster cal 351 in a 2577-20 case.

    I have to change the winding stem and crown as they are wrong.

    I looked up the stem and ordered 1106 but its completely wrong, Ronda list a stem ref 1360.

    What is the correct stem no. any ideas?

    thanks
     
  2. Archer Omega Qualified Watchmaker Aug 14, 2017

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    72203401106

    Cheers, Al
     
  3. Deaney Aug 14, 2017

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    Thanks Al
    Is that reference the same as the 1106 I already have? in which case it doesn't appear to fit.
    I think it should have 0.9mm stem and 1106 is bigger 1.13mm?
    thanks again
     
  4. Archer Omega Qualified Watchmaker Aug 14, 2017

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    I don't know if it's the same, because 1106 is only a portion of the full part number.

    I'm guessing that you are not a watchmaker, and might not be familiar with Swiss part numbering systems? 1106 is the part number for stems in general in the Omega world, so the preceding numbers tell you which movement the stem is for. In this case it's 340, being the base for the Cal. 351.

    If you ordered some other number ending in 1106, it's not going to be the right stem. There are hundreds of Omega stems with 1106 in the part number...

    Okay since you provided the tap size I just checked and the 72203401106 is 0.9 mm.

    Cheers, Al
     
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  5. Deaney Aug 14, 2017

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    Thanks Al
    It all makes sense, and you are right I'm not a watchmaker. Just keen to learn and have a go.
    appreciate your help
     
  6. Archer Omega Qualified Watchmaker Aug 14, 2017

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    No worries - if this is your first go at performing a service on a watch, this is probably not a good one to learn on. Please note that many parts for these are long discontinued, so if the parts in the watch are in good shape, you will want to be careful not to damage them.

    If you are just starting out, getting yourself an ETA 6497/6498 to learn on is a much more appropriate movement. They are large, robust, and easy to work on - this is why they are the choice of many watchmaking schools for students to learn on.

    Cheers, Al
     
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  7. Deaney Aug 14, 2017

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    The watch isn't coming completely apart, for the very reasons you say.

    Forgot to ask, the stem doesn’t seem that readily available, all the literature points to the larger thread type.

    Where would you suggest I look?

    Thanks again
     
  8. Archer Omega Qualified Watchmaker Aug 14, 2017

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    Glad you are not taking it completely apart - that's what servicing means so not sure what scope of work you would be doing.

    I'm not sure where you are getting the information from, but this is what Omega says about that stem:

    REF : 72203401106

    THREAD : 0.90

    TOTAL LENGTH : 20.70 MM

    Omega still has this stem available, and of course that's where I would order one from. But since you can't order from them, you will have to look - I have no idea where you have looked so far, but try watch material suppliers, eBay, etc. When it comes to vintage parts there's no short cuts - you have to put in the leg work to find them.

    Cheers, Al
     
  9. Deaney Aug 14, 2017

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    Thanks again
    much appreciated
     
  10. Deaney Aug 15, 2017

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    Thanks for your help yesterday. I have a couple of questions which probably shows up my lack of knowledge.
    Does the 2577-20 case (seamaster have a pendant tube (mine hasn't)
    Also the case clamp screw boss is missing, is this a major problem?
    thanks again
     
  11. Archer Omega Qualified Watchmaker Aug 15, 2017

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    Yes it will have a case tube - you don't say what case material you have but if it's stainless the tube is part #090ST2576.

    I'm not sure what you mean by "clamp screw boss" so I can't answer that one. If you can show a photo that might help...
     
  12. Deaney Aug 15, 2017

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    Thanks again
    The case is gold plated over stainless.
    The boss... is ... where the case clamp screws to the movement there is a threaded block 342/1023 this locates the screw
    mine is missing
    thanks again
     
  13. Archer Omega Qualified Watchmaker Aug 15, 2017

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    The plated case uses the same case tube as the stainless case does, so the number above is for your case also.

    You will need to have the movement secured inside the case, so you will need to replace that threaded block.

    Cheers, Al
     
  14. Deaney Aug 15, 2017

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    thanks again