Turntable won't spin-pls help!

I inherited an amazingly cool turntable/stereo from my Great Grandmother. It is a Zenith Stereophonic High Fidelity. Model MHT-15. I finally figured out how to get it up and running but the turntable will not spin! I took the back off of the unit and could see two discs spinning quite fast underneath the turntable but the turntable will not spin on it's own. Could this possibly be a problem with the belt? If so how can I even replace the belt-there is v. little room under there! I have not been able to find ANYONE in S. Florida who knows the slightest bit about these machines....ANY help would be GREATLY appreciated!!!

It probably has an idler wheel, rather than a belt. I never saw a Zenith with a belt.

Taking the turntable off usually reveals the drive parts.

If this is the variable speed 10 rpm to 100 rpm unit, those discs are the drive, and one of them is supposed to press against the underside of the turntable.

Other Zenith units have the drive above the plinth (chassis), so you can't see it from the bottom. You may be seeing parts of the motor. Usually the reason the turntable won't turn is that the rubber on the idler wheel is hard or missing.

Another possibility is that the record changer was turned off in the middle of a change cycle. Some turntable drives are unable to restart the turntable if it is stopped in this way.