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Seiko 7T32 main plate repair

systeman
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systeman WRT Addict

systeman

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This was an interesting repair to a Seiko 7T32 main plate, they're hard plastic.

The yoke spring stud on the plate broke away, therefore there was no spring compression.

I had to drill a small hole through the plate and insert a small diameter piece of metal stud as a fix.

Paper clip to the rescue. I used a small length of thin gauge paper clip for this and secured it with epoxy resin.

The setting lever had to be modified though to allow movement and so as not to interfere with the stud.

seiko 7t32 yoke stud repair

 

seiko 7t32 yoke stud repair dial side

 

seiko 7t32 setting lever modification

 

Oh what fun.

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rogart63 Distinguished Member

rogart63

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Had a YM57 movement plate. It looks like it is reinforced at that point . That is a very much same movement as the 7T32/34 

Sorry for the dark picture. But think you can see the stud? 

DSC08542.JPG

Edited by rogart63
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StuartBaker104 Distinguished Member

StuartBaker104

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Nice fix. I have one of these on my bench right now waiting my attention. It belongs to my Dad and I gave it a full strip down a couple of years bck, so was worried I had done something bad to it.

What were the symptoms? I have winding stem won't stay in and moving hands past mignight will not advance the date.

I wasn't really looking forward to stripping it down as I recall it being a pain to reassemble, and I've been looking for a working donor at a reasonable price (note that Cousins currently has the complete movement in stock at £62.50, but he says he'd rather put that to a new watch if it came to that)

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systeman WRT Addict

systeman

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The winding stem will loose proper function because the setting lever will not engage the yoke properly in normal, first and second positions.

If you attempt a repair, the stud diameter really only needs to be about 0.6 to 0.75mm and protrude above the main plate by a fraction more than the thickness of the yoke spring that engages it. Be careful when positioning the stud. You may see where it's broken away from, if not then either use the image on the right by Rogart63 above, or assemble the the clutch wheel, stem, yoke and setting lever and note the position of the yoke spring at rest. The stud position will be just under the spring. The spring needs to be under tension. Don't forget movement of the setting lever, it must not interfere with the stud in all three stem positions.

Regarding the date setting, that's probably something different. If its not turning over when you turn the stem in third position, the date wheel is broken and possibly a few teeth on the hour wheel as well. This can happen when someone tries manually to change the date between 9pm and midnight. An easy fix though.

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systeman WRT Addict

systeman

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Nice fix. I have one of these on my bench right now waiting my attention. It belongs to my Dad and I gave it a full strip down a couple of years bck, so was worried I had done something bad to it.

What were the symptoms? I have winding stem won't stay in and moving hands past mignight will not advance the date.

I wasn't really looking forward to stripping it down as I recall it being a pain to reassemble, and I've been looking for a working donor at a reasonable price (note that Cousins currently has the complete movement in stock at £62.50, but he says he'd rather put that to a new watch if it came to that)

I forgot to mention, if the date wheel or hour wheel need replacing, Cousins have these in stock. There should be no need for a new movement. The movement is serviceable, just don't use tweezers (only rodico) on any of the plastic wheels. Follow the assemble procedure in the service PDF from Cousins.

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GeorgeClarkson Super WRT Addict

GeorgeClarkson

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@systeman, that is a very nice fix, I had thought about doing something similar on all the 7t32/34/36 I have with similar issue, but never had the courage to do it actually. Might do it now that I saw your post, though. Could help me in repairing these watches in the future as well.

 

@Rob3rto: thanks for posting my video ;)

Edited by GeorgeClarkson
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