Speedometer not Working

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

Man i don't know from what you have explained i would think it should be working. Sorry i can't give any direction on this. Hang in thier sometime's post's are a little slow on Sunday's. I know when 4.3xj and Bluexj or Mudderoyxj get to this thread they will have some good idea's...