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Eta 7750 reset issues


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Hi!

I am having problems resetting the chronograph after servicing my IWC porsche design. This is far from my first rodeo on the 7750 and I consider myself quite competent with it. 

The problem lies in the reset operating lever. The pusher stem pushes too low on the reset lever and instead of resetting the chronograph it just flexes inwards. If I use pegwood or a movement holder, it resets correctly because it pushes higher up on the operating lever. 

I was thinking I should either bend the operating lever slightly outwards so it would hopefully overcome the flexing or loosen the cam jumper so it doesnt take as much force to reset. Any ideas and tips would be greatly appreciated if anyone has had a similar issue before, thanks!

Best regards,

AnttiVideo from Antti

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Terve Antti!

As you can see from my photo the error is caused by an position error it seems your hammer is riding on top of the chronograph cam .
Somtimes after an service the assembled hammer isn't in the correct place you can check that throght pushing the other button twice.

 

IMG_20190513_180038.jpg

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2 hours ago, HSL said:

Terve Antti!

As you can see from my photo the error is caused by an position error it seems your hammer is riding on top of the chronograph cam .
Somtimes after an service the assembled hammer isn't in the correct place you can check that throght pushing the other button twice.

 

IMG_20190513_180038.jpg

Moro!

I'm not quite sure what you mean. Reset works perfectly outside the case and doesnt require a lot of effort either. Ive attached a clearer picture.

20190513_214629.jpg

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What I mean when watching your original video video it seems like the hammer which makes the reset is lying above the Cam, thats why it doesn't reset and just flexes.

 

hammercam.jpg

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32 minutes ago, HSL said:

What I mean when watching your original video video it seems like the hammer which makes the reset is lying above the Cam, thats why it doesn't reset and just flexes.

 

hammercam.jpg

Aah ok! I checked and it is seated correctly  and if i push the operating lever with my (brass) tweezers it resets properly. I think I just got really unlucky and managed to find the only malfuctioning reset operating lever ever. Thanks for the idea!

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I'm a bit of a movement nerd and just want to learn a bit of what movements are used in which watch, yours look like one I had in a watch I owned a couple of years ago, an IWC Flieger chronograph with a C.7922 which also is an derivate of the 7750.

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  • 3 years later...
On 5/13/2019 at 6:13 PM, HSL said:

As you can see from my photo the error is caused by an position error it seems your hammer is riding on top of the chronograph cam .

Hello

I have the same problem with my eta7750. How can I correct the position of the cam? I appreciate any tips. Thank you

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