greetings. I’m fairly new to the forum and just got back into mechanical watches. I have had a vintage Longines from the 50’s that was beautifully made but I got rid of it because it was small at 28mm. It looked more like a ladies watch. It kept very accurate time however. Wanting to get a more modern version I purchased a Used LIV automatic with a Sellita SW100-1 movement. I read a lot about this movement and concluded it would a solid workhorse with a great reliability record. From what I read these are accurate from +-5-30 seconds per day. Unfortunately I’m getting nowhere near this and recently noticed that mine is off by 15 minutes in less than a week. I’ve never had a self winding watch so I’m wondering does this need to be moved back and forth for a period of time each day or should normal wearing time and activity be enough to keep it running. Seems to me 15 minutes slow within less than a week is abysmal..
Most likely it needs a full service by a watchmaker, which is standard for mechanical watches every 5-10 years. However, you can do a bit of diagnosis first if you are interested, to determine where the main problem lies. Try hand winding it 40 turns to ensure that the mainspring is completely wound. Then track the timekeeping over the next 24 hours by comparing it to the time on your phone. The results of this may help determine whether the problem is in the watch movement itself vs the auto-winding mechanism. But either way, the solution is going to be a full service by an experienced watchmaker.
Thanks for the response Dan. I will try your suggestions and report back. I guess I didn't realize I needed to hadwind this watch. I gave it a good winding and we'll see. Thank you again.
Yeah, I think you are right about service being needed. I did as Dan said and it's already 1 minute and 15 seconds off today from winding and setting it to the second yesterday. Completely unacceptable in my view. So something is amiss.