Ariens 1028 model#924116. Cleaning up the driveway this morning when machine stopped moving. It's happened a few times this winter but always seemed to move after a few minutes. I replaced the friction plate last fall and machine was working fine. I removed the belt cover and belt wasn't broken. Then i put it in service position and removed the bottom cover and the bottom pulley is loose. Has a lot of movement like a bad bearing. Is there a bearing or a bushing that maybe worn out? Easily replaced?