Yutani 120 LC Swing Problem

I've got a Yutani 120 LC and after I greased the swing table I first experienced a lot more noise than usual and then it got jerky and doesn't seem to want to swing at all. I'm guessing that some of the bearings are worn or broken. MY QUESTION: How do I repair this and how big of a job is it? Also, is it something I can repair myself? Thanks for any, and all, information that you can provide. Jim