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7750 minute counter issue


watchfellow

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Hi everyone,

The last two 7750s I've worked on have had the same issue where the watch will stop with the chronograph engaged right when the minute counter is going to roll over. I know this is a common problem and is usually solved by adjusting the minute counter jumper. However adjusting the jumper did not solve the issue. Either I am not oiling something correctly, or there is an issue with the finger on the chronograph wheel on both movements. I can't think what else could be a problem. I have attached a photo of the last movement if anyone has an idea by looking, as the chrono wheel finger is visible. Both adjustments look fine to me, but I would really appreciate any tips someone might give.

IMG_1768.JPG

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I am guessing this is akin to tuning a piano and is an acquired skill. One thing I saw on a 7750 I worked on was the finger was up high up on the gear. Not all of the finger face was touching the gear. I thought it was bent and I was thinking about bending it down. I decided to leave it alone as it was working.

Matt

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