I just got my hands on an old Zenith Allegro HR596W, I'm assuming from the 70's. Seems to be in good shape generally but the turntable doesn't run. I took it apart and I can see the motor spinning but it's not activating anything. How should go about troubleshooting this?Also, this is the first turntable I've come across that doesn't spin freely when you manually push the wheel. It feels loose enough if I keep my finger on it and turn it around, but if I give it a good whirl and let go, it goes around at best one full turn. I don't see anything obstructing it underneath and I've applied some oil to it but that didn't do much. Is this a clue to something or are some turntables just like that?