Wednesday, May 20, 2009

Saving MD-703S-7AV

The last 2 days have been a busy 2 days. Why? Well I found out one of my favourite watch has somewhat 'died' on me. I could no longer change the day or date on the watch. Otherwise it was working. If you look at the picture, you can see that the day is not align within the day window. SIGH!!!! What to do.... off to the friendly watch service man. He gave me bad news. The calendar ring is damaged and there is nothing he can do. He called up Casio and they confirm that the module (394) is no longer in production and has not been since the mid 90s.

Arrgggggg what to do??? Well, the next best thing, go to another shop where I get all my watch tools. They have lots of parts for lots of watches. The guy there had a look at the watch and gave me the same bad news. That was it, the end of my watch.

Spent the next 2 days looking in the Internet if there were module 394 for sale. Then an idea hit me today. Why not look for a donor watch. But wait, this watch was from 1988. So, would there be another watch using the same module? Yes there were, lots but all issued in 1980s and 1990s.

How difficult can it be, look for analogue Casio watch with day date function. Off I went to the watch shops (yes, shops). Nil joy. This is bad. Finally decided to go to a place called Shimenti where there are a number of watch shops selling vintage Casios (well mostly G-Shocks). First shop, nil, second shop, nil, third shop, again nil. I was about to give up when I notice a shop out of the normal walking path. In I went, and yes, an analogue Casio with 3 hands and day date function. Had a look at the watch, YES!!!!!! module 394. Bought the watch and home sweet home to do the transplant.

Now for the transplant. First clean the work area and get all the tools ready. Remove the strap and screw back.

Remove the back and remove the white plastic spacer/ movement holder to get to the battery. Remove battery.

Next remove the crown/ stem. This was made easier as unlike some quartz module, this one actually has a 'push' indicator to show where to push to remove the crown/ stem.

The case back and crown/ stem.

With the crown removed, it was as easy as turning the case around for the movement to drop out. Notice the notch at 12 o'clock? This is to align the minute ring to the dial and also the rotating bezel.

Finally the movement on the movement holder. OK it is not the right one for quartz movement, but it works.

Now to remove the hands. Always remember to protect the dial.

The hands. As you can see there are some oxidation on the hands. I decided not to clean it (actually I don't know how to .... :) ).

Finally the movement. So now to see what is wrong with it.

As you can see from the pictures below, the calendar ring is held in place by a number of notches in the center of the movement. These notches seem to be worn out. Also you can see that the calendar ring itself is damaged.

Now lets look at the dial. As you can see from the pictures below, there are some weld marks on the back of the dial. These are the weld marks of the luminous minute markers.

The dial is no longer white but have developed some yellowing around the edges. I think it adds character to the watch. Notice the tab at the 12 o'clock position? This is to align with the minute ring in the case.

So now the reverse can take place. Installation of the hour and minutes hand. We have to remember to adjust the time to 12 midnight so that the day date change before we install the hands. Failure to do so will result in the day date changing at a different time. Remember to clean everything, blower and a bit of Rodico helps.

The new module in place, batteries in and movement spacer as well.

Screw back the case back. Don't forget to lubricate the o-ring. Tomorrow off to the watch shop for pressure test.

And the watch, as good as new with another 20 years of life (more I hope).

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