Ok, here it goes. I have a Scag 52" Hydro older one, 1996 I think. The pulley on shaft of motor for the belt going to pumps keeps going bad. What do I mean by bad? The pulley keeps coming loose and will move on shaft(up,down & around). I have replaced it twice already but last time I cut the key in half for the pulleys. So when it come loose this time it moved the key back & forth and messed up the shaft. So I gotta replace motor. Oh well! My question is when placing new pulley on new motor how do I get this thing to stay put. There is 2 set screws on pulley but they seem to be coming loose.