I’m not positive they make replacements, though they may, but since you will have to pull it all apart to get to it I’d consider opening it up to see what you have going on inside. Sounds like a stripped gear or something. Albeit, I don’t have any experience with those. Just the earlier electromechanical and the quartz conversions for them. And I don’t think the quartz conversion can be substituted in an original quartz clock. Again, could be wrong on that though.