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Seiko 7548-700F Problem Prior To Repair


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Hi,

 

Need some help here before I tear down this watch.  I am fixing a friends Seiko 7548-700F Qtz (1981 Model) and, after putting in a new battery, it stops after running exactly 5 minutes.  If I advance the minute hand a bit, it starts running again.  When it stops, the second hand seems to stutter in place.  Any thoughts or experience here?  Is this a bad gear or dirt?  I do intend on disassembling an hand cleaning all the parts.

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I was searching for an original or a substitute movement and found this:

 

http://forums.watchuseek.com/f21/older-quartz-divers-7548-vs-7c43-movement-comparison-565340.html

 

http://jikanwatch.blogspot.com/2013/10/seiko-7c43-7010.html

 

But then, since you wan to fix it, I found this:

 

https://adventuresinamateurwatchfettling.wordpress.com/category/seiko/7548/

 

It is possible that old oil and dirt is preventing the wheels from moving properly...let's hope for the best and please, keep us posted on how you get on with the watch.

 

Cheers,

 

Bob

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Looks like a fun little movement to work on. Have only been inside a 7C46 which is movement plate is in plastic. This one looks more robust? Has as the 7c46 a lot of parts in the keyless work area. Tricky to work on. But rewarding when working again. I think the watch needs a good cleaning. Best if you find a service manual. So that you get the right lube. 

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Looks like a fun little movement to work on. Have only been inside a 7C46 which is movement plate is in plastic. This one looks more robust? Has as the 7c46 a lot of parts in the keyless work area. Tricky to work on. But rewarding when working again. I think the watch needs a good cleaning. Best if you find a service manual. So that you get the right lube. 

 

Yep. I do have the service manual and I am going to use Moebius 9010, D5 and KT22.....that should do.

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Do you prefer working on a movement with a movement holder or a watch cushion 

 

My understanding is that a watch cushion is not for working on the movement itself. That's the job of a movement holder, it holds the movement so you can do all sorts of manipulations in a way safe to the movement. The cushion is for crystal and other cased parts protection. Then you have the case holder for holding the case and do stuff too.

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Hand cleaning all the appropriate parts starts this weekend. Waiting for the new bezel insert and crystal to finish off the case. I still have not found out why the watch runs for exactly 5 minutes then stops with the second hand shuttering. Then, if I advance the time a bit, it starts again. Must be a gear??

From Canada

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