The Watch Site banner

1 - 16 of 16 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
I have a SQ100 which I have been told has a faulty movement, it runs a battery down in a few days. I have been told the movement which is 7149c, (the 1 could be an I tho) is obsolete and the Seiko service Centre do not have any. The watch repairer advised the net and via another I have been directed to this forum.

Does anyone have a spare movement I could purchase or alternatively I thought I'll just get another movement and get that put in and have been given all sorts of reasons why this won't work.

Has anyone any experience with a movement swap for these watches and any recommendations you could pass on.

The existing movement is 24mm across the flats and the case is 30mm and the movement is about 2mm deep, the existing has a date dial but I'm not that bothered about replicating that with a new movement
 

·
Registered
Joined
·
4,925 Posts
Hi, I think you may have given the wrong movement number ?, could you double check the back of the watch, which will have something on it like 7n49-0040 xxxx-xxxx . A few pictures would also be useful, but you may have to reply a few times to get your five posts minimum. Cheers, Dave.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
Just had another look with a magnifying glass and it's stamped 7N49C

The only information on the movement is as below

2 Japan
Seiko Time Corp
7N49C

Looking very closely it seems to have a bit of verdigree as though the battery has leaked
 

·
Registered
Joined
·
4,874 Posts
Is this the one.....7N43-8001, they do come up on Ebay from time to time, Ps And welcome.......Bob.

 

·
Registered
Joined
·
4,925 Posts
Please look at the case back, for the number I asked for - it makes life easier for us.
7N49 is normally a Railroad approved movement and is unusual.
Where are you located in the world? as this is an international forum.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
The case back is stamped 7N49 - 0040

I am located in Wakefield, England

My SQ100 has the day of the month but no day also mine does not have a second hand
 

·
Registered
Joined
·
844 Posts
Have you checked to see what is wrong? From your post, I assume it runs. If it consumes (known, new) batteries in a few days, then there is excessive current draw. I doubt that its a dead short...then the watch would probably not run at all. But might be a short through residue of battery salts causing the rapid drain. Evaluation on correct diagnostic equipment should give you a clue as to what's going on. Might be easier to repair than to try and find a substitute. Regards, BG
 

·
Registered
Joined
·
4 Posts
Discussion Starter #8
BenchGuy The watch does run with a new battery for a few days couple of weeks then stops again. I thought taking it into a Seiko dealer and asking him to fix it would be the simple thing as he would have the experience and knowledge. what I know about quartz watches and experience of was about zero - but it is increasing daily. Under the magnifying glass I can see the residue left by a battery, I don't know how long its been there, I always got the battery changed by a jeweller but not always the same one. I have been looking at watch toolkits on eBay and been thinking of investing. IMHO in the condition its in a the moment its worthless so I don't think I am loosing anything (unless someone know something I don't) any recommendation or advise on stripping and cleaning the mess out, would I need to take it out of the case, can I use solvents. I have a ready supply of electrical cleaner, any ideas what resistance I would be looking at if I put a ohm meter across the battery terminals, would that fry the movement?
 

·
Registered
Joined
·
844 Posts
Coil is 1.2-1.6 kilo-ohms. Total movement current consumption is about 1.2 micro-amperes. Your multimeter may help you with the coil resistance...but not with current consumption. Would suggest using a Witschi 4100, or later or equivalent model for evaluation. If you do not yet own a set of "watchmaker tools"...this is probably not the one to learn on. I appreciate its not worth much...so from that standpoint, there is not much to lose. But without a bit of study and a disciplined approach, there is not much to gain, either. Quartz watches are very reliable and somewhat durable...but the electronics are very delicate...so they don't tolerate mishandling very well. Unintentional introduction of very small contaminents will stop the movement. Cleaning battery residue is tedious and requires attention to detail, accompanied by complete disassembly and cleaning. Find watchmaker with a quartz analyzer...maybe he can show you how he evaluates it. Prior to that, read up on quartz watches and "virtually" disassemble/reassemble similar calibers using the Seiko tech sheets (which are very "step by step"). Hope that helps. Regards, BG
 

·
Registered
Joined
·
1,762 Posts
Unless cleaning the corrosion fixes the problem, I'd agree that you may be better off simply swapping out the old movement for a new one. It doesn't seem - from a quick search - that the 7N49 is available (I can't even find a spec sheet with casing dimensions), but you may find this site useful to determine if there is another movement with similar dimensions that would fit the case by measuring your old movement: http://www.seikodigitalwatches.com/seikocal4.htm It looks like the 7N39 is a two hand model (and still in production!) - perhaps that may work?

Anyway, may be a place to start....
Good luck!
-TW
 

·
Registered
Joined
·
4,925 Posts
7n48 is available, just leave off the second hand?
The main issue will be thickness of movement and hand height. You may need to measure it and compare with the link below.
Your watch was sold as super thin or ultra thin, I think.
I think yours also has some jewels in it, it should say so on the movement.
For dimensions - http://www.esslinger.com/7n48-seiko-quartz-watch-movement.aspx
 

·
Registered
Joined
·
1,762 Posts
7n48 is available, just leave off the second hand?
The main issue will be thickness of movement and hand height. You may need to measure it and compare with the link below.
Your watch was sold as super thin or ultra thin, I think.
I think yours also has some jewels in it, it should say so on the movement.
For dimensions - http://www.esslinger.com/7n48-seiko-quartz-watch-movement.aspx
If there's sufficient clearance between the dial face and the crystal, you could even add a second hand. Bonus! :)
 

·
Registered
Joined
·
4,925 Posts
If there's sufficient clearance between the dial face and the crystal, you could even add a second hand. Bonus! :)
True!, nice piece of lateral thinking:)
 

·
Registered
Joined
·
844 Posts
Sometimes there is more effort in trying to swap a movement, than there is in fitting a movement. Going back to your OP, it still sounds like the watch needs to be correctly evaluated by a competent watchmaker. If it functions, registering time correctly...but only uses too much current...it very likely can be serviced...and with less time and effort than "swapping" an ill-fitting movement. Take it to someone who is competent and find out what is going on. If they don't have a quartz testing machine which can determine quartz function, pulse function, rate deviation, and current draw, then take it to someone who has the correct tools. I worked with a very competent Cerfied Master Watchmaker...whose performance with respect to quartz movements was marginal. Quartz was before his time and he simply never developed the education, especially with respect to the electronic evaluation. Best of luck, BG
 

·
Registered
Joined
·
4,925 Posts
Sometimes there is more effort in trying to swap a movement, than there is in fitting a movement. Going back to your OP, it still sounds like the watch needs to be correctly evaluated by a competent watchmaker. If it functions, registering time correctly...but only uses too much current...it very likely can be serviced...and with less time and effort than "swapping" an ill-fitting movement. Take it to someone who is competent and find out what is going on. If they don't have a quartz testing machine which can determine quartz function, pulse function, rate deviation, and current draw, then take it to someone who has the correct tools. I worked with a very competent Cerfied Master Watchmaker...whose performance with respect to quartz movements was marginal. Quartz was before his time and he simply never developed the education, especially with respect to the electronic evaluation. Best of luck, BG
Totally agree - a decent watch guy should be able to fix it and is the preferable option. 7N49's are quite unusual, so try and keep it.
 
1 - 16 of 16 Posts
Top