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Valjoux 7750 stopped after stem replacement

Mickeycz

By Mickeycz
in Watch Repairs Help & Advice

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Mickeycz New Member

Mickeycz

Posted
Posted

Hello,

 

I'm new here and into watch/horology world as well. I recently tried to replace the dial on my 7750 watch.

1) Open the wathc case

2) removed rotor

3) removed stem (gentle push of remove stem pusher and pull the stem out)

4) removed the movement from the case

5) put movment to movement holder

6) removed hands

7) removed dial

8) put new dial

9) pressed the hands back, hovewer during setting it up I realized the movement is not running - even when I wind it up - it is solid/stable and not ticking at all.. 

Kind of out of ideas what can went wrong, the movement was functional correctly before..

 

Thank you for any ideas.

Mickey

 

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bjd1020 WRT Addict

bjd1020

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hello, I believe I did purchase/replaced the correct stem (bought from cousins uk) - measured it, did visual check before putting it in.  Before removing the stem, put it to the set positon.
 
Thanks for your replies 
Ok. Is the balance swinging. You should be able to wind it as that train is independent.

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saswatch88 WRT Addict

saswatch88

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9 hours ago, Mickeycz said:

hello, I believe I did purchase/replaced the correct stem (bought from cousins uk) - measured it, did visual check before putting it in.  Before removing the stem, put it to the set positon.

 

Thanks for your replies 

I think the watch is hacked. Does the balance move at all with agitation. If not then then you may have an issue with the hacking mechanism. Even with the hack the watch should still run when stem is removed because your supposed to remove the stem while its seated NOT clicked out in the set position. The stop lever may not be seated correctly with the sliding pinion. Still possible you have the wrong stem, did it state that is for a 7750?

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bjd1020 WRT Addict

bjd1020

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I think the watch is hacked. Does the balance move at all with agitation. If not then then you may have an issue with the hacking mechanism. Even with the hack the watch should still run when stem is removed because your supposed to remove the stem while its seated NOT clicked out in the set position. The stop lever may not be seated correctly with the sliding pinion. Still possible you have the wrong stem, did it state that is for a 7750?
^^^^^^^^what he said.

Some times those stems dont seat when you replace them. If you give it a good tug without depressing the stem release and it pops out there is your issue. I seriously doubt it has anything to do with the hand replacement. Sounds like a botched stem job. Snap a few photos with the crown all the way seated. Id say if the balance is not swinging its probably stuck in the hacked pos.

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Mickeycz New Member

Mickeycz

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Hello, thank you all for your responses. I wIll make better photos during the weekend as I have kind of time demanding job and watch play is more relax and I don't want to rush much to not make more damage than I already did..

Photos are made by phone and didn't know what to look for - what detail to focus on..

img_1032 - set position

img_1033 - operations position

The stem is correct one - I really did precise check when purchasing and even before putting it in - with magnifying glass and lot of light. 

 

What you mentioned the issue might be that I removed the stem when in "setting position " (as this is what I've read about 2824 stem removal and didn't think for 7750 it is different). 

 

Thank you very much for your help so far.

Mickey

IMG_1033.jpg

IMG_1032.jpg

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saswatch88 WRT Addict

saswatch88

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hard to tell but it looks like it is hacked.  Technically you can do it in wind or set position with the 2824 but because of issues with the lever slipping off the clutch they suggest doing it with stem in set position so if you are in the "set" camp, you should expect to depress the set lever when re-inserting. If you don't, the stem may move the set lever back into the quickset or wind position...in which case you've defeated the purpose of having it the "set" position to begin with. I prefer stem in wind position esp on movements with hack feature which is standard on 7750 but optional with 2824.

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