Pictures would help..most likely it is a snap on back which you pry off.most likely the rotor is loose or severely worn. Others may know better, but you probably could just remove the rotor and use the watch as manual wind only. Other possibilities include a donor watch to swap movement or get parts.
Hi, I guess I’m a watch collector. My wife thinks I may have a problem. Anyway I want to learn how to do some minor repairs and maintenance. I just happened on this form and am excited about it. I’ll go over the rules and be a great member. I live in Bessemer Alabama and work as a registered nurse.