I had never heard of the Archive 2150 before so I looked it up:
http://www.nessales.com/ebay/11737/Archive%202150S%20SCSI%20Tape%20Drive%20150250MB%20LR56637%20Half%20%281%29.JPGThere is a big drive belt visible in the picture above. My guess is that, if this has been sitting around for years, it has become stiff / cracked / stretched / broken.
I would check that immediately and replace it if possible (you can buy different length drive belts online). It might be possible to ressurect your drive.
If the drive belt is still intact and the belt has merely become stiff or shiny (won't grip metal capstans), you might be able to temporarily get some more use out of it by treating it with a plastic/rubber restoration product (like something that is used to tread automotive tires - usually found where car cleaning products are sold). That might work. Before that, I would try to rub the belt lightly with very fine grit sandpaper or steel wool, i.e. 400 - 1200 grit - (then clean the belt to remove any grit before re-installing).
