Mtd yard machine starts but rear wheels wont move

[Car collector]

I have a Mtd yard machine lawn tractor. It starts but the rear wheels won't move. We lifted the back and the wheels moved. One moves clockwise and the other counterclockwise. Does anyone have a suggestion as to what the problem could be and how to fix it?

 

[ILENGINE]

The parking disc brake on the right side of the tranny is stuck in the on position. May need to lube with penetrating oil to get it to move freely and not hang up everytime you step on the brake pedal, as when starting the mower.

 

[declid]

did u check the drive belts///???