7a28-7039 faulty Chrono reset pusher

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asjc240
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7a28-7039 faulty Chrono reset pusher

Post by asjc240 »

Hi a

I've recently purchased two(!) more Seiko 7a's, (7a38-7080 and 7a28-7039) where both sellers described their respective watches to have issues and sold 'as is'.
IMG_3474_11zon.jpg
IMG_3474_11zon.jpg (238.49 KiB) Viewed 188 times
With this Seiko 7a28-7039, I've run into a strange problem. I've yet to find time to delve any further than removing the caseback and movement, but some ideas on what to look for when I do is never bad. The watch keeps time and all functions work as is, except for the Chronograph reset. The 4-oclock button is completely non-responsive even after removing the movement and pushing it directly with a flathead. It does not reset the chronograph nor the chrono seconds hand. However, the moment I pull the crown out to the first step - which is used to zero the hands, the watch performs the zero reset. I'm unable to adjust the chrono second hand zero.

Additionally, upon unscrewing the caseback I'm greeted with a Finger tension spring that is not displaced but bent over backwards by the caseback. I also see some very slight hints of rust, suggesting something deeper going on with this watch. I'm wondering if the lume has been refinished - if there is rust, or moisture ingress, I would not expect to see lume that is brighter than all three of my other 7a's. Anyways, I think first things first I have to figure whats going on with the chrono reset - any ideas on where to look once I'm in the movement?

If I'm not describing the problem well enough ask away!
Alan

Apologies if creating two separate threads for my two watches is unnecessary, but given the different nature of either watch 'issue', I felt it might be better to have them separate. Admins feel free to move either thread to somewhere that may be more applicable, thanks!

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Seiko7A38
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Re: 7a28-7039 faulty Chrono reset pusher

Post by Seiko7A38 »

Check the condition of the switch lever(s). They are made from spring steel and sometimes rust, reducing electrical conductivity. Also check the cleanliness of their contact posts embedded in the '710' (green plastic insulator spacer).

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