Can't get machine to move

[concretedoggie]

Was given an older machine as a project. Cleaned up the engine and got it running. Here's my question. When the shifter is in neutral, should I be able to spin the pulley on the rear end by hand? It seems to be stuck. Wondering if clutch is not engaging. It's jacked up and when I turn the tires, the pulley doesn't move. Could there be a pin that sheared? Thanks for your input ahead of time.