I have a 1990 XJ it had a slip yoke eliminator kit installed. Since I have been driving it the speedometer doesn't work. I checked to make sure that the geer is in place on the out put shaft. The speedometer does work if you turn it will a drill. Does any one have any other Ideas on what to check. I don't know much about speedometer but them seem simple is there some thing I am missing?

Thanks, Brian