2836 Configuration question

[krpster]

Hello all,

I recently received as part of a package deal an ExpII with an ETA 2836-2. However, the watch was not functional (known at the time) but I thought I would have a go at fixing it up. Opened her up and sure enough an ETA 2836-2 was to be found in the case fitted with an incablock shock protection. Very cool So the problem was that the watch wouldn't run and the crown with stem would just pull right out. Immediately this led me to believe the keyless works were messed and that the stem release was jammed. Sure enough this was true. However, the odd thing for me was finding this stem attached to the crown

Apparently this is known as the helicoidal sqaure stem. However, in my research it shows that this stem was used in the older 2836. Mine is clearly stamped with the -2 on it. Also, after digging into the keyless works I discovered that here also it appears that the workings are of the older variety.

Where this really got me was when the yoke spring went flying out of the case (marked in red in the picture) which now I must find a replacement.

So first of all my question out to you movement experts is...did the 2836-2 ever come fitted with parts like this or do I have a bastardized movement in my watch? Secondly do you believe it is possible to retrofit with newer parts to have keyless works like the newer movement with a standard stem? The only reason I ask this is that the helicoidal stem is a bit more finicky when inserting and removing. I have found through playing with this one that it needs to be in time setting position for removal/insertion or the works get thrown out again.

Thanks

[RWG Technical]

I would like to see pictures of the complete movement, especially a close up of the ETA and caliber markings.

As far as I know, all 2836-2's are the same, and this isn't one of them. I have only ever seen that style of stem in a 2671, never in a 28XX series, and the keyless works is not a 28XX design, at least not one you will find spare parts for...a yoke from a normal 2836 is not going to work in place of that one.

It appears to be a very old something, exactly what I am not sure.

[krpster]

Thanks for the feedback Zigmeister. According to this spec sheet HERE the stem and keyless works that I have are from the early version of the 2836. The "Yoke Spring" I am missing is part no 440. When the movement changed to the -1 and -2 series shown HERE among other changes to the keyless works this yoke spring was eliminated in place of the combination part no 445/2 called the "Combined Setting Lever Jumper". I have confirmed with Bob Ofrei that 440 is still available so I will order a few as I am sure I will lose another one or two installing the new one.

For posterity here are the pictures of the entire movement as well as the best shot I could get of the caliber markings. The balance wheel covers them almost completely so tough to get a clear shot.

From this I must surmise that our chinese friends made this "Swiss" movement using a newer main plate and older mechanical parts. In their defense however, I do not know how old this watch is so.... Another indication of my deduction is that when the watch is running it sounds much slower than my other 28xx pieces, for example a 2824-2 and a lot more like my 6497.

One other feature of note is the setup to obtain the "GMT" hand. Basically it is a slave to the hour wheel at a 1/2 reduction so it cannot actually function as GMT but more of a 24hr indication. The extra crappy part is that the hand size to fit this wheel is 2.2mm!!! I have not been able to find hands of this size so I will reuse the previous hands.

Anyway, thanks for the help. I'll get this piece going yet

[RWG Technical]

Wow, that is an old one...the "Patented" stamped on the dial side I normally see on movements from the 70's/early 80's.

I'll never figure out ETA caliber numbers, this is clearly stamped 2836-2, but shares almost no parts with the modern version of the 2836-2. Certainly if you ordered what's stocked today, you would not get parts to fit this version.

An option on the GMT gear, is to turn down the hand seating area to accept a hand size you may have in stock, should be simple to do in the lathe with a wheel chuck, let me know if I can help...

[krpster]

Yup. A strange bird for sure. Thanks for the offer, it does look like there is plenty of meat there to turn down. I may take you up on it depending where this project goes. Ideally I want to change this ExpII from a black faced version to a white. I found hands that look right but they are designed for the 2893 which has a 1.8mm GMT hand. Given the overall oddness of this thing I am not sure I'll get a dial to fit either So this may just stay as is....for now

Thanks again!

[spen]

HI I WAS SEARCHING ABOUT THIS PROBLEM AS I HAVE THE EXACT SAME MOVEMENT AND PROBLEM WITH REGARDS TO GETTING THE STEM AND YOKE SPRING.APART FROM MINE IS STAMPED WITH 2824.2 I LOOKED ON COUSINS AND FOUND THAT THEIR PARTS ARE DIFFERENT AS I ORDERED PARTS AND THEN FOUND THAT THEY WERE NO GOOD SO I HAD AN OLD ETA MOVEMENT WITH PART OF THE KEYLESS WORKS STILL THERE EG YOKE SPRING THE ONLY DIFFERENCE WAS THE SHAPE AS THE ORIGINAL WAS LIKE AN OMEGA SIGN WITH LONG LEGS. THE 440 PART NO IS SPOT ON BUT I COULDNT GET IT THATS WHY I TRIED WAT I DID AND IT WORKS OK BUT WOULD STILL LIKE TO GET THE CORRECT SPRING FOR IT. IF POSSIBLE COULD YOU TELL ME IF THE 4 FLATS ON YOUR STEM ARE THINNER THAN A STANDARD ETA 2824/2836 STEM CHEERS

[spen]

FORGOT TO SAY MINE HAS RADO STAMPED ON ROTOR GOT ME ALL CONFUSED

[Rolexman]

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