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Seiko 7T42 Service Walkthrough


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On 6.9.2016 at 1:24 AM, GeorgeClarkson said:

And finally the base plate, naked.

seiko_7t42_003.jpg

Most impressive George!  Its nice to see that all kinds of watch movment are fixable, I have only doing this for some moths. And it gives so mutch inspiration to move on futher....

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  • 2 years later...

Hi GeorgeClarkson,

Great rebuild story. I came across this searching for help on my fathers 7T42-6AA. The minute hand stopped working and several UK watch repair shops have told him it cannot be repaired. It has some sentimental value to him and I would like to try and get it repaired.

I was wondering if you could advise if there are common/specific issues with this movement that could cause the minute hand issue and if it is possible to repair? Or would I be able to find other 7Txx movements and swap them into his case?

Thanks in advance,

Rich

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The problem you have is with this movement many of the parts are plastic so if a pinion or wheel breaks the only coarse of action is to replace the movement. If the hand has just come loose on its pinion it could be re-seated. Perhaps a picture might help.

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5 hours ago, RichB said:

Hi GeorgeClarkson,

Great rebuild story. I came across this searching for help on my fathers 7T42-6AA. The minute hand stopped working and several UK watch repair shops have told him it cannot be repaired. It has some sentimental value to him and I would like to try and get it repaired.

I was wondering if you could advise if there are common/specific issues with this movement that could cause the minute hand issue and if it is possible to repair? Or would I be able to find other 7Txx movements and swap them into his case?

Thanks in advance,

Rich

Hi Rich, I just received the notification. As clockboy mentioned, these movements are made of mostly plastic parts. A complete swap is, though, not the only solution, also because complete working movements are becoming rarer by the day. That fault you described can be caused by a damaged hour wheel. Replacing the wheel could easily solve the issue, provided you have be the spare to do it. Let me know if I can be of any help, since I do service these watches, and have so some spares left.

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4 hours ago, GeorgeClarkson said:

Hi Rich, I just received the notification. As clockboy mentioned, these movements are made of mostly plastic parts. A complete swap is, though, not the only solution, also because complete working movements are becoming rarer by the day. That fault you described can be caused by a damaged hour wheel. Replacing the wheel could easily solve the issue, provided you have be the spare to do it. Let me know if I can be of any help, since I do service these watches, and have so some spares left.

Thanks George, can you point out the hour wheel in one of the photos you’ve posted on this thread? If that is the problem, do you have a spare I could purchase from you? 

It will be about a week before i see my parents and get more info on the issue with the watch.

Thanks,

Rich

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2 minutes ago, GarethRogerson said:

Hi my brother has this watch 7T42-6A00 and the circuit needs replacing done anyone have any ideas where we can get one.

Hi Gareth, these movements are not produced anymore, yo your best chance is to search for a spare donor watch on ebay that will not cost an arm and a leg. I do have some spares, but I do not sell them since I use them for the watches I service for my customers, sorry.

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