My Seiko Grand Quartz 9943-8000

A watch with a story

I bought a watch in 2023: the Seiko Grand Quartz 9943-8000. I had become so enamored with it after reading this blog post from Adventures in Amateur Watch Fettling—which I highly recommend you read too. To quickly summarise, I love this watch because of:

  1. its highly accurate twin quartz movement—capable of keeping within ±10 seconds yearly
  2. the history of said movement, which was groundbreaking engineering at the time, and
  3. its good looks!

The watch is even considered a part of Grand Seiko's own history, as explained in Vol.4 of "A history of Grand Seiko in ten chapters".

Needless to say, I really wanted this watch.


I found my watch on eBay in March. I had been combing listings try to find a good price; you could either pay a lot—upwards of $1000 AUD—for something in mint or slightly mint condition, or pay as little as $200-$500 AUD in an auction for something very much used or aged. We are talking about something more than 40 years old, so the used instances were not always in the best condition.

Eventually I settled on someone selling a watch from Sydney, Australia. It mostly looked good, but I have to admit, I may have been a bit too excited to get one after having looked for so long.

Picture of my watch on eBay
My watches original eBay listing

The band wasn't the original, but other than some wear and tear, it looked good. The patina looked great too, in my opinion. I did confirm the colour of the watch was two-toned (mistake #1).

When the watch arrived, I was ecstatic, mostly because everything was intact and I was able to semi-confirm the movement was there and functioning. That is, I wasn't scammed out of getting a watch stuffed with something else. However, the honeymoon was short-lived when I discovered a few things:

I had clearly purchased a watch that had its gold plating stripped (or really badly polished off) and was likely not put back together correctly afterward. The casing also felt sticky, like some kind of glue had been used when it was reassembled. Not a good sign, especially if I wanted to be sure the watch was to not have any moisture get into it.

To be honest, I wasn't super upset; I had the movement first and foremost. And sure, the case and crystal weren't in the best shape, but I had a blog post that documented in great detail a refurbishment of the watch. This meant I had something I could show a professional watch repairer—or use as a guide to do so myself.

Despite wanting to keep the watch, part of me still felt I was ripped off a bit. Fortunately, I was able to reach the eBay seller and negotiate a partial refund based on my concerns.

Watch repairers

Between March and April 2023, I set off to find a professional watch repairer that could help me fix my watch. Fortunately, I had a handful of options between Sydney and Newcastle. But nothing really panned out.

One Seiko-certified repairer was able to confirm the movement was intact; that the case was very likely stripped of the gold; and was highly doubtful the crystal installed was correct. They suspected the only way to fix the watch would be to get a brand-new crystal—Seiko part 300WB4GN00 or 300WB4GA00. I can wholeheartedly say these crystals are essentially impossible to find. I contacted 5 suppliers across Australia, the USA, and Europe, who all had the same response: obsolete or discontinued.

Another repairer thought I was wasting my time. They also concluded the watch was likely "glued" together, possibly because the gaskets were non-functioning or the last "repairer" didn't have the right tools. They suggested I not do anything with the watch, especially if the movement was keeping time. I tried to explain the importance of the 9943 movement and trying to make it hermetic again, but they didn't want to get involved. They suspected the work would likely be thousands of dollars worth of effort and politely asked me to move along.

The other repairers simply did not work with watches of this "vintage" age.

Eventually, after some careful consideration—and a lot of googling—I decided I would try to take the watch apart, clean it up, and put it back together. If I was going to do this myself and could keep the costs down, I would also look into getting the case re-plated with gold. I don't think I was ever going to convince myself to be happy having this watch be "two-toned".

Repairing it

I am proud to say I'm a pretty handy person. I can usually fix things around the house, including appliances, electronics, etc. But I had never dared work with a watch before. Of course manual and automatic movements are not anything a novice should attempt to take care themselves. But a quartz movement seemed like something I was willing to tackle now. Especially again because I had a guide to follow. Even more so, that guide provided specifications about replacement parts I would need. So I wasn't completely flying blind.

The first thing I needed to do was to get some proper tools. Trying to keep costs down, I went to Amazon to get what I knew I needed:

On April 22, I decided to open the watch up.

Using the case cover remover, I was able to gently pry the inner casing of the movement.

The next job was to press the bezel and crystal out.

Next up, I did some cleaning with soap and water and then stored the outer casing for plating.

Gold plating

To be continued...I'll be back once I find someone to do the plating 🤞