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Forum Home > Parts Info, Tech Tips and Tinkering > Seiko 7A38-7280 reset problem

Sdm107
Member
Posts: 4

Hi everyone

I'm a new member here having just bought my 7A38-7280 on eBay!

For some reason I couldn't see this model on the forum list of models but perhaps that was just me being a bit blind.

Anyway, so I picked up my Seiko on eBay. I've given it a good clean (the bracelet was unbelievably dirty). The crystal was badly scratched so I purchased a crystal on eBay and installed this myself. It's keeping good time. The chronograph starts, stops and the split seems to work. The reset doesn't work however. Thanks to this forum I was able to find the manual and I tried resetting as per the instructions but none of which worked. There appears to be no way of resetting the timer back to zero. The only thing I haven't tried is removing and reinstalling the battery but I suspect this makes no difference?

I removed the caseback to remove the dial. Pushing the reset lever manually does not reset the timer so the problem must be something more buried away. I'm not experienced in stripping down a watch so I'm going to stop there. I cannot see any rust inside or around the dial at all which I guess is a good sign.

 

Is there anything else I can do? If not I'll have to consider having the watch serviced. In which case can anyone recommend someone who can service this model in the U.K.?

 

Thanks for all your help in advance.

 

Best wishes, Stuart.

 

March 12, 2017 at 7:57 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 12355

Hi, Stuart.

Welcome aboard - and congratulations on your first purchase - even if it isn't working 100% correctly.

There are still a LOT of topics that I need to create in this forum section, besides the 7A38-728x family.

Your post is more of a general technical query, rather than being '7A38-xxxx model specific', so once I know you've read my reply ....

I'm going to move the thread here: http://www.seiko7a38.com/apps/forums/show/6600711 Parts Info, Tech Tips and Tinkering

As you can see, I've already edited your topic title to reflect this. There are many similar / related topics in that forum section. ;)


First (a pretty basic) question for you:

When you had the dial / movement out of the watch case and tried activating the cam of the switch lever manually, without success, did you replace the crown / stem in the movement ?


Secondly, have you tried the inbuilt self-test (with the dial / movement installed in the watch case) ? With the crown pushed fully home, you simply hold the pusher at 4 o'clock in for 2 seconds. All three chronograph hands: 1/10s sub-dial; central sweep second hand and 30 minute counting sub-dial should complete one full revolution and return to their starting point (even if it isn't Zero). Related to that, have you tried pulling out the crown to the first click (setting position) and tried advancing any of the chronograph hands, by repeatedly pressing their related pusher ? (The 2 o'clock pusher advances the 1/10s hand; the 4 o'clock pusher advances the centre sweep seconds hand and the 10 o'clock pusher advances the 30 minute counting hand). Does any of the foregoing work ?


March 12, 2017 at 8:53 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 12355

As a matter of interest, which 7A38-7280 was it you bought ? There have been quite a few listed on eBay recently.

This is the most recent UK eBay sale I could see:


http://www.ebay.co.uk/itm/232144836377

RARE USED SEIKO CHRONOGRAPH QUARTZ 7A38-7280 MAN'S WATCH




Although the seller claimed in his description it was 'still working fine', it's clearly suffering from a stuck reset pusher @ 4 o'clock.


March 12, 2017 at 9:32 AM Flag Quote & Reply

Sdm107
Member
Posts: 4

Hi - many thanks for replying and the help.

I can't honestly remember if the crown was in when I tried to reset manually. I will have to try this. 

I tried the manual test by holding down the reset button for several seconds but it didn't do anything.

I got the fully stainless steel version of the one in the photo! I absolutely love this watch!

Thanks.


March 12, 2017 at 11:48 AM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 12355

O.K. So I've moved your topic to the relevant forum section. You didn't properly answer all of my questions, particularly regarding:


Related to that, have you tried pulling out the crown to the first click (setting position) and tried advancing any of the chronograph hands, by repeatedly pressing their related pusher ? (The 2 o'clock pusher advances the 1/10s hand; the 4 o'clock pusher advances the centre sweep seconds hand and the 10 o'clock pusher advances the 30 minute counting hand). Does any of the foregoing work ?


That said, I've an idea where the problem may lie and if it is that, it's a relatively easy thing to fix (you could do it yourself).

Have a read of these couple of existing threads in this forum section:

http://www.seiko7a38.com/apps/forums/topics/show/8576775 Subdial hands will not reset correctly to zero ?

http://www.seiko7a38.com/apps/forums/topics/show/9397929 Problems with stem and resetting chrono' hands


March 12, 2017 at 12:32 PM Flag Quote & Reply

Sdm107
Member
Posts: 4

Hi, sorry.

Pulling out the crown to the first click and repeatedly pushing each of the buttons does nothing. 

It looks like you missed out those links but I'll have a look through the forum now.

Thanks again for your help.


March 12, 2017 at 12:35 PM Flag Quote & Reply

Seiko7A38
Site Owner
Posts: 12355

O.K., that second link I posted more or less answers it. As I wrote previously, it's pretty simple to check and fix it yourself.

Leave the movement in the case, with the crown stem inserted (the safest way to work on a watch in a situation like this).

Remove the battery and unscrew the 7 screws retaining the movement's anti-magnetic back-plate and battery positive plate.

Carefully lift off the PCB and put it somewhere safe, being extra careful not to lose the tiny gold-plated rotary step switch.

Check the height of the setting lever (per that thread) and if necessary gently bend it upwards so that it's approx. 1.00mm above the top surface of the green plastic '710' insulator spacer (per the photo and technical manual extract).


March 12, 2017 at 12:50 PM Flag Quote & Reply

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