@drhoo printer repair is a royal PITA because manuals are scarce and repair parts are hard to come by. Nobody wants to repair a printer since it is cheaper to buy a new one. Anyhow, you did not tell us which exact gears etc. It will help if you add lots of images etc. Whenever you run into issues like this. Here is a document that will be of interest to you. If nothing else it’s a start. [document|5569]
Here is a guide that will tell you how to post some images of what you are looking at [guide|21499]