I have a yardmachine snowblower 31am63ef729 and cannot seem to get the auger to work the way it used to. I noticed that there seems to be some slack in the cable from the handle to the auger. When I pull on the cable the blower works much better. My question is what do I change the cable or the belt. The belt looks fine but there is slack in belt. Also how do you change the belt. Does the cable get worn ou after time?