Overhaul Procedure – Omega Speedmaster (Omega 1861)

Hi guys, another watch breakdown I thought I would share. You can check out the original blog article here:

https://ashtontracy.ca/2019/09/12/overhaul-procedure-omega-speedmaster-omega-1861/

After a spate of vintage restorations making their way through the door, I have had a few modern watches come through. Up today is an Omega Speedmaster with the 1861 movement. It was a straightforward overhaul with only a few parts needed. It needed a new setting lever screw and operating lever.


The watch was uncased.


Dial and hands are then removed, exposing the dial side of the movement.


I then flip the movement and get to work on the movement side.


First, I remove the bridge that covers the chronograph recording wheels.


The hammer, chronograph wheels and a few other chronograph components are removed.


I slowly remove the rest of the chronograph work.


Now the base movement is ready to dis-assemble.


I remove the balance.


Then the barrel and train wheel bridge are removed exposing the gear train. Note the excess oil and the rust present on the ratchet wheel. I use a fiberglass brush to remove it.


Movement side is done.


The broken setting lever screw.


The movement is now stripped completely and ready to clean.


The watch is in its tray. This is where I store the case, dial and hands for safe keeping whilst the movement is serviced.


Once cleaned, the balance spring is centered and made flat.


The lower barrel bridge is installed.


I put the new mainspring in the barrel.


The gear train is then put into place.


Hand setting and winding work.


The barrel and train wheel bridge, as well as the escape wheel bridge, are ready to go. I check the end shakes as I go.


The pallet fork and balance are installed.


Once the base movement is put together and timing is checked, the chronograph components can now be put back in place.


The bridge is installed.


More of the chronograph work.


Slowly building.


More chronograph componentry.


Almost done.


The movement side is practically complete.


I now finish the dial side and perform all the necessary checks.


The dial is then installed.


Now, the hands.


The watch is now ready to begin testing.

Not going to lie, I got a more and more anxious as I kept scrolling down. Watch overhaul is not something I have a heart, experience or knowledge of to tackle on my own!

Rust is not expected and will indicate a sealing issue most of the time from the crown.

Where does the battery go?

just kiddin'

Awesome! Nicely documented!

Nice to see such fantastic looking movement.
Interesting that the setting lever screw was broken, I guess someone had been a bit over enthusiastic when tightening it, makes you wonder why they had the case open in the first place

Thank you for sharing, an eye opening process indeed.

Thanks for the very informative post,

kind regards Max

Fantastic pictures, thanks for sharing. Just out of interest, how long did the entire process take (from opening the case to getting it all back together)?

I allow 6.5 hours for the service of an 861. Some take a little longer, some are a little quicker.

Thanks, guys I'm glad you like the posts!

Puts the cost of a service in perspective!

Thanks for sharing the process and excellent pictures.

That's hilarious - I had the same subtle but building anxiety. A lesser version of how I felt watching the trailer of Alex Honnold's free-solo of El Capitan. No way I could get through the whole documentary.

Exactly so, particularly for us sweaty-palm types 😉