Trading out watch movement

[Isildurs_bane]

Just curious.
My second hand smiths prs29A (2013) has the eta 2804 movement which is basically the 2801 with the date complication added.
So if I were to one day replace this with an ETA 2801 I found would it be a direct swap after installing the dial and hands? Would I have an issue due to the 2804 having the date wheel and new eta 2801 I have not having it? I am thinking a space difference of the date wheel now not being present.


Am I making any sense? I can try to be more clear if needed.

My own limited knowledge from research shows both movements have the same height of 3.35mm and obviously same diameter at 11.5 lignes. What I am having a hard time understanding is that the date complication wheel should add a bit of height to the movement right? At least .5 mm surely?

Anyway, like I said, maybe I'm not understanding something. Perhaps there is a recess which allows for he difference of date wheel vs. no date wheel?

[walkerwek1958]

Both movements are interchangeable. The date wheel doesn`t add any height, trust me I know about these things!

The 'ghost' 1st position on the crown can also be modified, changing the setting lever spring for a 2801 variant will get rid of it. Clearly a job for a watch repairer who's skilled in the art, don`t try this at home if you don`t know what you're doing.

[Isildurs_bane]

Thank you. Yeah with putting in the 2801 with no date complications I would not need to think about the date position on the crown. Would I need a shorter stem though?

[walkerwek1958]

Thank you. Yeah with putting in the 2801 with no date complications I would not need to think about the date position on the crown. Would I need a shorter stem though?

Why are you considering swapping the movement? Sounds to me like your trying to solve a problem that doesn’t need solving, my advice is to leave well alone and if the watch develops a problem in the future send it to a competent repairer.

[Isildurs_bane]

I have a spare ETA 2801. Not planning to swap soon but when the day comes. I live out in the mountains and there is no one around here I could think of to send a watch to. In the mean time I would like to learn more about working on these. I used to build ASTER gauge one steam locomotives. Not the same I know but I like tinkering. Not about to mess with mine until it’s broken but I like to think about the steps when the time comes is all.

[walkerwek1958]

I wouldn’t advise ‘tinkering’ with it yourself unless you’ve developed your skills on other watches.

[Isildurs_bane]

Thanks for the advice. I’m not going to just blindly start tinkering. I am going to learn and practice though because I am passionate about mechanical watches because of wanting to learn to work on them. I have actually a few eta movements. one just to pull apart and practice with.


I’ll be taking a class this summer on the SW210 movement.

[Isildurs_bane]

One of the spare 2801 movements was missing the stop lever for seconds hacking. I bought one and installed tonight. All working well. Now I need to learn how to lube the movement which will be my next task.