The 6139A was Seiko’s (and arguably the world’s) first automatic chronograph, released in March (?) 1969 and featuring quickset day/date, a 30 minute sub-register and a column wheel with vertical clutch. The most iconic of the models featuring this movement is the 6139-600x which came in numerous permutations, the most famous of which has come to be known as the Pogue after William Pogue who wore the watch on board the Skylab mission between 1973 and 74.  His watch, featuring the gold-coloured dial, sold at auction in 2008 for a little less than $6000.  Mine, a 6139-6005 from November 1973, cost considerably less.

It arrived in decent cosmetic condition but had been described by the seller as non-working. Here is the original photo from the seller:

Looks ok, doesn’t it? I opened up the back to see if anything obvious was amiss with the movement and was greeted with the sight of a wobbly rotor assembly, the cause of which was one loose and one missing screw. So off came the rotor assembly:
and if we look carefully we can see why the watch isn’t running. The missing screw is jammed between the barrel and the movement ring, preventing any power being transmitted from the mainspring to the balance:

So, with the watch equivalent of the Heimlich manoeuvre performed (simply turning barrel to get some power into the mainspring did the trick), the screw was free and the movement sprang into life. With the rotor assembly refitted, I removed the movement and fitted it temporarily to another case while I worked on cleaning up the original case.

Here is a shot of the dial, looking rather nice. Not perfect but it has a rather gorgeous, honeyed look to it that is very appealing.

Here’s the movement, rotor side up, and installed in a spare case:

Those of a nervous disposition may want to look away at this point. Here are a couple of shots of the case with the bezel removed, but exposing lots of lovely grot:

and with the crystal removed

we can see that plenty of elbow grease will be required to lick this into shape. Next we remove the rubber crystal gasket and gasket holding ring. We must remember to install this the right way up when it all goes back together:

Underneath the gasket ring we see the circular spring that sits between the inner rotating ring and the case.

So with everything out, first a good scrubbing with a toothbrush and toothpaste, a good working over with some pegwood sticks to remove the more stubborn regions of dirt and then sanding pads and paper to sort out the worst of the scrapes and dings to the case. Here’s the case post clean with the inner rotating ring and spring refitted:

The next job was to remove and replace the hardened gaskets on the crown and pushers. Here is the crown and stem with the old gasket and some DNA removed from the reverse side of the crown:

In order to fit the new gasket, you need to unscrew the stem and gear for the rotating ring from the crown. With this now completed for the crown and chrono pushers we are on the home straight. With the movement refitted to the now cleaned case we are ready for the new crystal:

Here is a comparison of the old crystal with the new, a reproduction sourced from the US:

Finally everything back together, and only two attempts to get the bezel properly aligned (which incidentally was not the bezel that came with the watch but the one originally fitted to a spare case I had)

Now for a few finishing photos of the watch on its new bracelet:

Interestingly, the watch ran extremely well with the mainspring unstuck, all functions working properly and keeping almost perfect time without any further attention required.

Now to its twin, this one a blue-dialed 6002, completely original, and in pretty decent condition with just a tatty crystal, a few case dings and plenty of grot.  A thorough case clean, some refinishing to eliminate the dings and a new Sternkreuz crystal it started to look the part.  However, although this one was keeping good time, the chrono reset function was not working properly.  A bridge too far for me at the time and so off it went for a repair and service (courtesy of Richard Askham).  With the watch in fine fettle back from service, I finished it off with a new reproduction bracelet:

and finally a couple a couple of closing shots showing the two together