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Posted

Trying to open this Seiko 7N43 and nothing works! Any ideas what may be the problem?

 

post-253-0-36243300-1408480702.jpg

 

Here is the whole watch:

 

post-253-0-15583500-1408480710.jpg

 

post-253-0-01142600-1408480717.jpg

 

Thank you in advance!

 

Robert

 

Posted

Hi Geo,

 

Thanks for the advise, as always very accurate and to the point.

 

I thought this watch needed to be opened through the front or I was missing something here. Before I damaged it I thought to better ask. The tool you mention is amazing. I got the bergeon one and it opens everything but this watch!

 

Now I know what to do thank you, and can use more drastic measures... Seiko, the gloves are off!!! :growl:

Posted

Yeap! The back is off. Used a 1.10 mm screwdriver, ordered the crystal and soon it will be like new! I'll post pictures.

Posted

Thank you Geo and thanks for the -- as always -- good advise.

 

==================================================================================================

 

By the way, I was reading my previous posts in this thread and I believe I need to clarify -- for other readers -- that I was trying to open the back of this watch unsuccessfully using all sort of approved tools in my not small **BLEEP**nal. The reason for this is a broken crystal I wanted to replace as seen in the picture. 

 

I reached a point where frustration made me doubt, and think that the movement was supposed to be extracted from the front (from the crystal side). Luckily we had this forum here to save the day and I was cautious enough to double check -- in this case with Geo -- that indeed this watch opens normally from the back as my original assumption was. I then threw caution to the wind and used more drastic measures to open this watch. A case of a stubborn case I'd say, pardon the pun.

 

====================================================================================================

Update:

 

After opening the back and extracting the movement I found it in a very well preserved estate despite the broken crystal -- and years who knows where -- but very dusty on the dial side. The dial will need a good "fairy" magic -- or as we do on this side of the pond "palmolive" -- to be back to its original looks, as the dust seems to have stuck -- even caked -- to it. A blow with the bergeon pump won't clean the dial. I'm starting to think that in some instances those "B*" tools are over rated! In any case, I have grounds to believe that some of that dust may have found its way to the movement but haven't done a thorough check yet.

 

Expectations are great and a brown lizard wrist band is also on the way to substitute the existing and worn black lizard one. It will probably go better with the case gold plating despite the black dial.

 

As an aside, this watch uses a Seiko PC2i movement readily available for about US$20 almost everywhere. So I suppose there is room for error here.

 

At this point, I'm pondering if I should spray clean and oil the existing movement as per Mark's video on servicing a quartz watch or simply spray it given it is very compact...or maybe use compressed air from a can?

 

post-253-0-15282800-1408750424.jpg

post-253-0-89797400-1408750430.jpg

post-253-0-24968900-1408751346_thumb.jpg

 

Any suggestions or comments to help me decide -- before I remove my gloves again  :) -- are appreciated!

 

Robert

 

 

 

 

  • 2 weeks later...
Posted

Well, I like to finish what I started so I'm getting to a happy conclusion of this thread with a picture. Here is the sum of all my efforts and a small experience to share:

 

Seiko crystal was ordered from CousinsUK and replaced.

Replaced the battery

AND replaced the back gasket that was pressed into the "pressure groove" and therefore cut by the back when snapping close. It was preventing the watch to be opened!

 

The dial was cleaned to remove all the dust accumulated through the years in a drawer with a hole in the crystal!

 

 

 

 

post-253-0-24611000-1409750355.jpg

  • Like 2
Posted

I used a hand held blow pump and rodico mostly since I didn't want to mess with a movement that can be purchased here for about $20 and is still available (I found I have a spare in my quartz movement drawer). It is working perfectly so the fix was mostly cosmetic. Not too glamorous but the picture doesn't make justice to the actual looks of the watch.

 

I should make a correction to the above post since the movement is a 7N43 not a PC21 but I was fixing another watch at the time and got mixed up while writing this thread.

  • Like 1
Posted

Many quartz movements are very cheap, to the point of not worth overhauling the movement. It is a lot quicker (and cheap) to simply replace the whole movement. Once the movement is replaced with a new one, I found that the old movement is excellent to be stripped down as a practice for a beginner like me :)

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