Grand Seiko Battery Change
“Oh Nooooo!” That was my thought as I picked up my Grand Seiko yesterday morning realizing that it was dead. Time for a new battery. Well, I knew this day was inevitable; the day I would have to change the battery on one of my high-end Seikos. I just wasn’t sure which watch it would happen to first. I have a couple of Prospex divers that are 6 or 7 years old that I’ve been expecting to die any day now, so I was surprised to see that this 3-year-old Grand Seiko was the first to go.
Luckily, I was very prepared for this moment. Quite a few years ago, I splurged and bought a nice case opener. This Horotec is the best watch tool I’ve ever purchased. If you use it properly, it would be impossible to mar a caseback (or crystal retaining ring) with it.
Once I got the caseback off, I was looking at the anti-magnetic dustcover.
I smiled when I looked at the inside of the caseback. It’s actually nicer than what I’ve seen on some highly regarded Swiss watches.
Okay, here’s the shot everyone has been waiting for. This is a Grand Seiko 9F61 movement. I couldn’t help but notice that the “Seiko” on the battery was lined up with the writing on the movement. I wonder if that was intentional or just a coincidence?
I don’t care if this movement is quartz or not, it’s lovely. The screws are highly polished, all the edges are nicely beveled, every holes is perfectly chamfered, there’s a wonderful starburst pattern to the plates, and it’s properly set in its case. I can’t tell you how many Eta/Valjoux movements I’ve seen that don’t get these simple things right. Here’s a closer view:
Okay, the battery has been popped in, the watch looked very clean inside, which is not always the case. The gasket looked great, but there’s no harm in putting a little grease on it.
Now the back has been screwed back in. As expected, the Horotec left no evidence of its use.
Turning it over, I’m happy to see that it’s ticking away fine. Feels good!

June 6th, 2008 at 4:53 am
Great post Pete, thanks for the tutorial! Beautiful GS, too;-)
June 6th, 2008 at 5:45 am
Hi Pete,
Concise, informative, fascinating topic, rarely-seen movement pictures (best 9F pictures I’ve ever seen). Great work — thanks for posting!
Regards,
Bryan
PS — Wonder which watch you wore to the office today?
…
June 6th, 2008 at 5:53 am
Thanks Fatpants and Bryan,
Believe it or not, I actually don’t have the GS on today. I really wanted to wear it, but I’m playing golf right after work, and it’s going to be about 90 degrees today. I didn’t want to leave that watch in my very hot car for 3 or 4 hours while I played so it’s a trusty old solar G-Shock on my wrist.
When I get home, the GS will be worn.
June 6th, 2008 at 6:28 am
Hi Pete,
Can understand not wanting to wear your GS golfing, or leaving it in a hot car for hours. Enjoy the links; your post made my day!
Regards,
Bryan
June 6th, 2008 at 7:34 am
Hello Pete:
This article of your about opening your Seiko GS and
replacing its battery goes to the heart of being a
watch enthusiast. We enthusiasts love learning everything
about watches, how to feed them, how to clean them, how
to baby them.
We love spending endless hours discussing minutia about
how the screws are polished, how the holes are properly
camphered, how the edges are beveled.
Some other people may write about these items, but
rarely do we get such beautiful photos to illustrate
what is being discussed.
Being a watch enthusiast is, I would say, a way of life.
Thanks.
June 6th, 2008 at 8:30 am
Hi diverwatch,
Thanks for your comments. It’s nice to know that there are others who appreciate some of the finer details of watches in the same way I do!
petew
June 6th, 2008 at 1:30 pm
Very nice post Peter. I really enjoyed this one, esp. the Horotec bit. I’ve been toying with the idea of owning one, having seen that model and a crystal press at a local parts house. For now, my GS battery change will be handled by the friendly AD here.
I like that dial on your GS. If my memory serves me correctly, it’s a limited edition time only with a patterned “paper” dial. 2003 eh? Gorgeous. Are you the first owner?
From the posts I’ve read on various fora, you have a top-class Japanese watch collection with some very interesting models. Hats off to you.
Thanks for the post,
June 6th, 2008 at 5:56 pm
Hi Vandice,
Nice to see that you are a GMT+9 reader. You are lucky to have trustworthy Seiko AD near you. I do not have that luxury! My SBGX039 is a model that was released around 2003 as part of the “Master Shop” series. The dial is very unique with it’s cross hatched lines and laser engraved GS logo. I bought mine new from Seiya a few years ago and it has remained one of my top ten Seikos.
petew
June 7th, 2008 at 9:17 am
Hi Pete,
I was interested to learn your Grand Seiko is called by Seiko “Super Magnetic Resistant” (SMR). The chart below shows it rated at “SMR40000″ (40000 A/m) — significantly higher than JIS1 (4800 A/m — the threshold for a watch designated as “antimagnetic” by ISO 764:2002) and JIS2 (16000 A/m) ratings.
As shown in the image below, there is an antimagnetic shield below the dial, as well as the one you showed located under the caseback. The shields are identified with the yellow-colored Kanji.
I was also interested to learn Seiko purposely made dial the same 31.5 mm size as the 1950s Crown Seiko (case is of course larger on the Grand Seiko at 38.2 mm); the hands and hour markers have a gray coating for greater visibility, which Seiko wrote they plan to continue using on Grand Seikos where visibility is important.
Regards,
Bryan
June 7th, 2008 at 3:04 pm
Hi Bryan,
Thanks for the translation information Bryan. I’d never figured out what that “1950″ referred to in that description since I couldn’t translate the embedded information. Funny, I never realized it, but there are some old Crown styling cues on this watch.
petew
June 8th, 2008 at 8:08 pm
Hi Pete,
I stumbled across this one, appears to be a relative of your watch:
SGBX045
Regards,
Bryan
June 10th, 2008 at 6:39 am
Hi Pete,
Great to see the unveiling of your Grand Seiko’s 9F61A beautiful looking module. It’s a stark contrast from Seiko’s other quartz calibers that gravitate towards function than form. I also found it intriguing that the Seiko battery was lined up perfectly with the Seiko text next to it.
Perhaps more care is given at the factory to the GS quartz models and the worker who installed the cell aligned it nicely in accordance with the assembly procedures?
I’m awed that Seiko designed the watch to resist up to 40,000 Amperes/meter - that’s extremely impressive for a non-tool watch like the SBBN quartz divers!
Loved the read!
cheers,
Stratman.
Very nice post, thanks!
cheers,
Stratman
June 12th, 2008 at 4:14 am
Hi Stratman,
Nice to see you here. Since I’ve written that battery change article, I’ve noted that in all the pictures I’ve seen of 9F movements, the battery writing is lined up with the movement writing. It must be a specified procedure at Seiko to do this. Now I fee bad, I didn’t properly line up the replacement battery. Bad Karma!
Bryan, I have seen that SBGX045. It was released a year or two after the 039. I’ve actually been tempted to pick one of those up and at the price listed in your link, it really is a good deal.
Thanks guys,
petew
June 12th, 2008 at 4:37 pm
That’s a very handsome watch, Pete, inside and out. You have me convinced that I need the fancy caseback opener now.
Best regards,
Jeff
June 12th, 2008 at 7:39 pm
Hi Pete,
It’s interesting to compare your picture of a 9F movement with one of an 8J movement. Both are rated to +/-10 seconds per year, and although the 8J movement is hardly “pretty,” give the 8J credit for being so thin that it can fit inside watch cases like the Credor that are just 5.5mm thick. As you know, the 8J movement is also used in some Grand Seiko models—including models with 38mm wide cases. I assume the plastic spacer is really big inside those.
It’s impressive to compare the size of the 9F movement in the 38.2mm case of your Grand Seiko with the 8J one in a Dolce that is 33mm wide and uses a plastic spacer. Why is the 9F movement is so “big”?
Regards,
Bryan
June 13th, 2008 at 6:01 am
Hi Bryan,
That was very interesting to see the 8J movement. I was always under the impression that the 8J looked very similar to the 9F, but I was wrong. It’s obvious that cosmetics was more of a design consideration with the 9F series. Not knowing enough about quartz movements, I can’t speculate as to the size differential between the two. Do any GMT+9 readers have any ideas on this?
June 13th, 2008 at 7:02 am
Hi Pete,
I did a bit of research on why the 9F movement is so much larger than the 8J one.
The 9F movement has features the 8J lacks, like:
1. Twin Pulse Control Motor
2. Automatic Backlash Control Mechanism
3. Instant Date Change Mechanism (1/2000 second day/date change)
4. Sealed components designed to keep out dust for 50 years
I think we both knew about these things, but one tends to forget. Anyway, I think these extra movement features make the 9F bigger.
Regards,
Bryan
June 13th, 2008 at 7:04 am
Hi Jeff,
One unfortunate thing about that Horotec opener is that the prices have almost doubled since I bought mine a few years ago. Incidentally, mine is a low end model, I have a friend who bought a nicer Horotec which is absolutely amazing. One of the many attachements he has is a set of rubber suction cups that attach to casebacks through suction. They seem to be able to open up any style of caseback that we’ve thrown at it with no metal to metal contact.
Thanks for reading,
petew
June 15th, 2008 at 7:07 am
Horotec tools are nice but just like the watch winders, very overpriced
Nice work for sure, you will not see me anywhere near a case like that:)
But, i am lucky, i have a friend who dabbles in this a bit
June 15th, 2008 at 3:34 pm
Thanks for this information Bryan. I suspected that the 9F had at least the sealed mechanism that the 8J lacked, but a recent post by a person on the WUS HEQ forum alluded to the fact that this was not the case. As always, your research and thoroughness is appreciated!
petew