Hello. Found some similar topics posted here from 2010, but it seems a sligtly different problem in my case.
The UN Maxi-Marine with Asia 23J movement, with secs and date at 6, working PR at 12, has a problem with the autowinding function. The rotor is moving, but seems jerky (both directions). Only way to gain PR is to wind manually (carefully!). The PR loose juice when I am wearing the watch.
After studying some pics of similar topic, I found that on my watch, I can see throuhg the caseback (sapphire see-thru), the spring lever on one side of the tooth wheel gear, is in odd position. It has slipped out of its normal position against the teeth of the tooth wheel, and sits atop the wheel, thereby obstructing the autowinding, and possibly also making the movement of the rotor look jerky. My idea is to open the caseback, then use a small tweezer and try to push the spring lever back in its opposed position. Is there any reason I should avoid trying this? What happens if I remove the rotor? Will parts fly around the room and all is ruined?
Here is the pic.The second pic is the actual watch. The Cr red arrow is the correct position. The Wr arrow shows where the spring lever sits on my watch.