I have an older Honda 3011 Riding Mower that keeps slinging the blade belt off. I replaced the belt but the new one also comes off. There appears to be no slop.
Thanks

Belt pulleys usually have some sort of keeper pin that redirects the belt back on if they try to slip off. Theses look like a 1/8" steeel shaft sticking up around the pulley but about a 1/4" out from the pulleys edge. Do you see them or a place where one broke off. Also check your spring loaded tensioner pulley, the one that moves when you engage the blades, to see if it has excessive wobble with the belt off.

Thanks ballengerb1, you were right. The keeper had come out. Also replaced the tensioner pully. Working well now.