From your desctiption, I'd say you've got more wrong with that unit than just a needle. Perhaps the idler wheel is also messed up, you have one or more leaky capacitors in the thing, or a ton of out-of-spec carbon comp resistors. Do you have a SAMS photofact for that unit?
http://www.antiqueradios.com/forums/viewtopic.php?f=1&t=204039wow! ceramic disc caps mostly, just a few papers, so that will be cheap to fix up!
Bad news though is your unit uses a static cart, those are a pain in the butt to find, so a lot of people will convert them over to magnetic and modify the pickup circuit to deal with the lower voltages that come off of it.
Get yourself a SAMS so you at least have part numbers to look up on that needle though, I do not have enough experience to tell you who made that changer for caphart though. Make an overview of it, and the problems it's experiencing and post it to youtube, there's a lot of good vintage radio/record player guys hanging around there who seem to help people!