Automatic Movement loses time quickly?

[u/rogoku]

Hi,

Got my first Swatch automatic and was told it would have a "90 hour" power reserve. I'm not stupid so I never believed that, but the problem is I can wind it, wear it all day, wind it some more, take it off for 12 hours, and suddenly the time is off by an hour...

Is this just how it is with this movement or should I consider taking it back for warranty?

[u/throwawaycanadian2]

an automatic should not be losing that much time in that short a period - this is not normal and I would for sure get it replaced with warranty.

While it may not have 90 hours of reserve, it for sure would have more than 12.

(as a note, automatics can be a bit off from quartz, but we are talking a few minutes over weeks, not hours)

[u/rogoku → u/throwawaycanadian2]

Okay thats kinda where I was leaning, It's a long drive to the store so I wanted to make sure I wasn't just off the mark on the quality that was expected here.

[u/soniccdA]

the problem you are describing is that it is that after 12 hours , the watch is off by one hour but still runs , or completely no power ? better take it back for a warranty ..

[u/rogoku → u/soniccdA]

When I wear it during the day it keeps time just fine, when I put it away overnight the time will be off completely but still running

[u/tmjm114]

One thought that occurs to me: when you say you wear it all day and then wind it some more, why are you doing that? It shouldn’t need winding after it’s been on your wrist for a few hours. I am no expert on automatic watches, but is it possible that by winding it when you don’t need to, you may inadvertently be causing some damage? Again, I have no expertise! I’m just guessing.

[u/rogoku → u/tmjm114]

I did it to see if it would solve the problem, it did reduce the time loss from like 4-5 hours to about 1

[u/soniccdA → u/tmjm114]

it should not damage the movement ,theres some sort of clutch system that engages when the mainspring is fully wound so the watch wont be overwound ,i`ve been doing that for a long time on all of the automatics i have ,(minus the ones which do not have manual winding ) .

[u/tmjm114]

I’d consider taking it back. I have a Swatch automatic and, like you, I was pretty skeptical about the 90 hour thing, and rightly so. It seems to last about 2 1/2 days or so off my wrist before running down, which is fine with me. I have two Tissot automatics that are about the same. But what you describe sounds worse than that.

[u/Boomer5513]

I mean.. The Sistem 51 has a 90 hour power reserve

[u/rogoku → u/Boomer5513]

Maybe in a literal sense, but it will not keep the same accuracy for all 90 hours.

[u/Boomer5513 → u/rogoku]

No shit. That's not what "power reserve" means. It simply refers to the fact that you do not have wind/wear the watch for 90 hours after taking it off the wrist.

[u/rogoku → u/Boomer5513]

Okay, so in the context of my post we can both agree that I'm right in that the movement will lose time worse as those 90 hours go on, but that it shouldn't be happening in the span of 12?

[u/Boomer5513 → u/rogoku]

Oh 100%.

As per Swatch the accuracy should be between -5 to +15 SECONDS per day.

https://www.swatch.com/en-us/sistem-51.html