Hi guys, I've been posting in the vintage forum for a couple months, but this time need to see if anybody know of a reliable source for the Omega calibre 1164 Valjoux 7750 movement. I bought a Seamaster Pro Chronometer on Ebay with box and papers knowing that it had water damage and was for parts or service. After taking it apart the salvage of the parts isn't looking good due to the extensive corrosion. Even after ultrasonic and polishing the wheels are shot. I'd like to ideally get the Omega 1164 as opposed to the generic 7750 in Ofrei. I'm thinking that keeping the internals Omega official will help resale some day (let me know if there is any reason not to follow this line of thinking). Thanks for any help guys.

 

Incidentally, I do have the original rotor in perfect condition. thought I'd mention since some people have tossed around the idea that it was the only upgrade to the generic 7750 platform.

 

Keep an eye out on eBay. They pop up. Never for a cheap price though.

 

Hello - are you a watchmaker? Just curious as a stock 7750 has some differences from the Cal. 1164. First you would need to make sure all the hand heights are the same for the stock 7750 and the specific Cal. 1164 that is in the model you have (different dial thicknesses can lead to different hand heights so longer posts on all the wheel that have hands on them).

The decoration is quite different than a stock 7750, and not just the rotor. You would also have to remove the day functions, since the 1164 only has the date. Also the shape of the automatic bridge is completely different on an 1164 than a stock 7750.

And of course, a movement from Otto Frei will not be a certified chronometer.

I have bought one from Omega before to replace a very rusted one I serviced last year....





Just getting it out of the case was quite a chore:





Brand new movement with chronometer certificate:





All good in the end - used the dial and hands again:



Movements are not inexpensive no doubt, but if you want it to be a proper Omega and not a franken/fake, then an Omega movement is the only option IMO.

Cheers, Al

 

Salt, and then left for 4 months after exposure....it was essentially one rusted mass.

I do have maybe a dozen parts from this watch that were not completely useless, but mostly screws and smaller items that didn't manage to get wet. The guy who sent it to me said he was going to take the major parts and mount them in a frame for his father - his father left the crown unscrewed when in the ocean.

Cheers, Al

 

Thanks for the replies guys. I'm not a watchmaker, but a hobbyist. I do possess enough knowledge and tools required to perform a full service without a proper timing as the only device I don't yet have is a timegrapher. That being said I'm very comfortable with vintage movements at this point, but chronos are still a bit daunting to me (wouldn't mind learning more about servicing a 7750 for example if anybody has any resources). In any case, I ended up ordering a new 1164 Omega movement from a Swiss ebay dealer since I noticed the non chrono and sans rhodium plating from ofrie, but did not know about the different wheel shaft lengths. My movement did not look quite as bad as the above pictures. Many of the parts did ultrasonically clean up good as new, but probably about 15% of the wheels did have pitting so I thought it would be best to start fresh. The only thing I will need to find more info on is going to be positioning the hands on the new movement so that they are in accurate positions without too many tries since I don't want to damage the hands or scratch the dial. It's the 2559.80 model in case anybody was wondering.

 

Al, how do I go about not ending up in the rust dept. I have put the case (all crowns closed) in the ultrasonic without any water seepage issues (I know it's not even close to any type of vacuum test, but it's a close analog in terms of the environmental pressures that I'll be exposing it to). The prior owner stated that he kept the helium valve open and thought that it caused this, but without rising from the depths of the deeep blue, I thought that the gasket alone would keep water out?

 

Always enjoys your learning session Al, thanks........

 

Not sure what a 2559.80 model is. There should be 2 more digits to the model number, so if you can provide those (or better yet the serial number) I'll look it up on the Omega Extranet and check to see if this one has specific issues with regards to hand heights.

For information on the 7750 work, there is sort of a "7750 for dummies" thing from ETA called Swisslab. Here is the link to the 7750 instructions:

http://www.eta.ch/swisslab/7750/7750.html

Of course this assumes you know how to properly prepare a mainspring barrel, oil, use epilame, check end shakes, and all that other basic stuff needed to properly service a watch.

For setting hands, what equipment do you have for this? A hand press will be much better than hand held tools, and for setting on the chronograph hands you will need to actuate the chronograph mechanism. So you will need to start, stop, and reset it several times while setting the hands on to make sure they are on properly and lined up.

I have a movement holder specific to this family of calibres as shown here:



This has the ability to actuate the chronograph mechanism, and also works for other 775X versions. Probably a bit much for you as this holder alone is about $400.

You need a method of supporting the jewels that are for the wheel you are setting the hands on. Chronograph hands have to be pressed on very tightly to resist the forces during resetting. They are tight on the posts, and if the jewels are not properly supported, you can change the end shake and potentially damage the watch movement. If you look at this photo of some of the movement holders I use, you will see many have small posts coming up in the middle of the hodler. The 7750 is the large silver one, and there you will see many posts - thgese are turned up to meet the jewels on the underside of the movement:



On your other post, how are you determining if the watch is leaking after putting it in the ultrasonic tank? Are you performing a condensation test after?

Cheers, Al

 

Thanks so much for all the info Al. I will say that I haven't used any type of epilame product as I thought that it wasn't necessary with modern oils like Moebius. As far as endshake of pivots, I don't know official protocol on this as I've only been using a visual inspection under magnification. I have greased a hand wind barrel spring, but not a auto wind spring just yet. I only have the hand held watch hand tool and not a press which is why I'm thinking I may take that part to watch maker seeing as how the second hand is under such speed on resets. I was initially thinking of setting the hands just prior to date change as a marker of midnight and resetting the chrono, but I'm not experienced enough to do this comfortably on a watch not intended for practice (also don't have the specific holders as you do). My holder is a clamp type without a bottom so it wouldn't touch the movement necessarily but, activating the chono levers would be difficult. Also, I mistyped, the watch is 2599.80 ref# 178.0504/378.0504 I don't have a serial handy. As far as the condensation test, I used a hair dryer to warm the case and added a drop of water to the crystal without fogging. I do enjoy learning this as I go and since I'm working on my own watches I don't fear too much, but this is by far the nicest in my collection so I'm really appreciating your input on how to go about this. I'm riding the line of my limitations as an amateur on this one. Lastly, do you have any tips on removing scratches from the band. I was able to remove most with my fine sanding pad, scotch brite pad, and fiberglass scratch pen under magnification, but a few deeper scratches remain. I was considering using the fine abrasive finishing wheel on the dremel to remove the scratch and go back to the pads and pen to refinish afterwards. I will say that I'm happy that this case is difficult to refinish since I'm assuming it will also be harder to scratch when wearing.

 

Just saw a complete movement listed on ebay yesterday for $750.

 

Now I know it is possible to purchase the complete movement separately. Nice!

 

The escape wheel and pallet fork jewels are always treated with epilame in every Swiss lever escapement watch I service. As well as the reversing wheels are done on this calibre and pretty much all automatics.

The primary end shake to be concerned about on a 7750 is the barrel arbor end shake - should be between 0.005 and 0.015 mm. The train wheels are otherwise normal with regards to their end shake requirements.

I would suggest getting someone to put the hands on for you - this is not an easy task for a beginner and as noted you can damage the movement by not supporting the jewels.

I checked the movement in that watch and when your new movement arrives, you can place the dial and see what things look like in terms of post heights for mounting the hands compared to the original. If you want to know for sure you would need to disassemble the dial side until you can access the free cannon pinion (ETA part number 243) - measure it's height - should be 4.05 mm tall.

For a proper condensation test, a hair dryer may not be hot enough. When I do this test I use a hot plate that brings the case to 47 degrees C, which takes about 30 minutes on the plate to be sure. Then I place one drop of room temp. water on the crystal, leave it for 1 minute, then wipe it away and use a loupe to check for condensation. If there is any the case failed and seals must be changed. On this one if you really want to be 100% sure, you would need to change the HEV complete, pushers complete, case tube, crown, and case back seal. To change all these the case must be heated to loosen the Loctite and remove the various tubes, so the crystal would be pushed out and a new seal required there as well. There are specific tools for removing and screwing in these tubes, but you could probably remove the old ones with a large diameter cutting broach, and screw them in using your fingers and tightening with the crowns.

Refinishing is a whole other subject. WOSTEP is only now starting to teach things like this in watchmaking schools (SAWTA schools have been doing it for a few years now). I can't really give you a lot of advice there, because unless you have a proper polishing station (variable speed motor plus all the buffs and compounds) nothing I do would be useful to you. I see peop,e recommend "Scotchbrite" pads for creating brushed finishes, and I suppose that would work, but it's not the "proper" way of refinishing a bracelet, and you really need to be careful of creating uneven surfaces.

Hope this helps.

Cheers, Al

 

Thanks so much Al. Had some repair work questions for you. Sent a PM.