Hello, I was trying to replace my deck drive belt on a 2012 Ariens 42'' Hydro Tractor, model 936048 and I noticed the top of one of the pulleys which actually is plastic is broken. The pulley itself looks fine, but the top half has a plastic cap is split. I attached a picture as I'm not certain I'm describing the part correctly. The picture is taken with me standing at the back of the tractor, the pulley furthest back is fine, its the next pulley shown which had the plastic part break. The belt that goes to both of those pulleys is fine. I called Ariens to see if I could order just the plastic top half as it screws into the pulley itself, however they indicated they don't have the parts because that is considered part of the transmission. I was able to track the part down, but was told I need to purchase the entire pulley for $65. I'm fine doing so, but wanted to see if anyone else has had a similar issue? The reason I was replacing my drive belt is because the belt kept falling off (esp if break was on). I'm not sure what the plastic is for as it doesn't look like the drive belt makes contact at all? Any insight anyone can provide is appreciated. Steve