Have you tried just putting the turntable back on, plugging it in, and engaging the drive? It might just go ahead and turn.
First take the turntable and turn it by hand. It should move freely and easily, and it should not hang up and stop, even if it is in the pickup and shutoff cycle. You may have to apply a little pressure to get it to turn in shutoff cycle, but it should not take a lot of force.
Take a look at the surface of the idler wheel. It should be firm, yet pliable, and not hard or shiny. Rubber should not come off on your fingers when you feel it. If rubber comes off, idler needs to be replaced. If the surface is hard or shiny, the idler may not be able to transmit torque from the motor to the turntable. You can clean up a shiny surface by holding idler against the motor spindle and applying some 220 grit wet or dry sandpaper to it. DON'T GO CRAZY! A little is a lot here. Just sand it enough to expose a new surface. You can also soften the idler with a product called Rawn Re-Grip, which refurbishes idler wheels that have gone hard. It is available at http://www.parts-express.com
It may also be that the spring that pulls the idler wheel toward the motor is not adjusted properly. If you look at arm to which spring attaches, you will see a screw in the middle. This screw adjusts the spring tension. You should be able to loosen the screw and shift position of arm to tighten spring. Also idler carrier may be monkey-snotted up and not moving freely from side to side.
These are typical failures found on these idler drive jobs. If needed, you can get idler wheel refurbished for about $45.00 US from a number of companies such as Svalander Audio. But I would first check idler contact and carrier motion, and try sanding it and checking spring first.
And good luck from that pliable, but poorly surfaced old guy,