Omega Seamaster 166.064

[anilv]

I've had this cushion cased Seamaster for a few years and wore it off and on. For some reason I was under the impression it had a10xx series movement which is not really as nice as the 5xx / 7xx series.

The movement is running fine but the movt seemed to be a bit loose in the case, noticeable when the crown is pulled to set the time. Also there was a gap between the dial and the chapter ring at the 2-4 o'clock position (above picture is after, didn't take a 'before').

Well I took it apart last weekend to see if I could fix these issues. First thing I was happy to note is that the movement is a 752, not a 10xx, can't explain why I thought differently. The next thing I noticed was that the movement was stuck fast in the case. Taking a closer look it seemed that the movement ring/holder is not correct for this case being too small. To solve this problem someone had jammed some bits of old o-ring around the edges to hold the movement in place. This bits of o-ring had degraded into a gooey like substance which was a pain to remove from the case and movement ring. The caseback gasket was also as hard as a rock.

 

 

The movement ring fitted to this watch, while did not seem to be correct for this case, was correct for the 752 movement. Fitted to the movement/dial the dial and stem-hold lined up perfectly. This made me step back and re-look at the movement ring again. I noticed that it had a groove which seemed to be made for an o-ring, also the case had a sizeable gap which seemed to indicate that there would be something (absorber) which would fit this gap and afford some level of bump protection, similar to what Certina did with their DS series. The absorber would not be a full ring as hole for the stem was in the middle of the groove in the movement ring, again, this is what Certina did as their movement absorber had a gap for the stem..

 

Well to cut a long story short, I had some 1mm and 1.5mm section o-rings and these fit in well enough so that the dial sits flush and the movement is held firmly in place. The bump-protection offered by the o-ring is not much as compared to the ring in the Certina DS it is much stiffer, the one in the Certina being more 'spongy'.

Anyone have any experience with this model and can shed some light on this model?

Another issue I found was this big bump on the caseback sealing surface which corresponds to one of the tool slot on the back. Probably someone used a chisel to get the caseback off in the past? Had to file and sand it down otherwise it would've ripped the new caseback o-ring.

Finally.. as this has a 752 movt.. I think I'll be wearing this more often so it deserves a service soon! I can explain why having a different movement will affect my attraction to a watch but that's how it is!

Anil

Edited September 1, 2016 by anilv

[anilv]

Well I finally discovered that the part I need is not a ring but 4 individual 'bumpers.

The omega part number is 088NS9401 and this is how it looks like.

One mention of it back in 2013 gives the price at GBP8 per piece!!

Anil

 

[Geo]

An interesting post Anil.  This is not something I have seen before, and I've worked on quite a few Onegas.

[bobm12]

Geo! Onegas are different watches! Anil's is an Omega! Just couldn't resist, sorry Geo!

As Geo said, that's a very interesting piece of information, I was expecting a ring too...the price is not a surprise though!

Good work Anil!

Cheers,

Bob