Rear discharge normally discharge is larger clippings that a side cutter. Rough cut mowers are rear discharge and a friend who says problem with rear discharge finish mower is it will discharge much like rough cut, it cuts it and throws it out. What a side discharge does a certain amount of mulching as it cuts.
I have the Ventrac Model MC600 60-inch rear-discharge deck, to which my dealer attached the Ventrac No, 70.8088 mulching kit prior to delivery. This is my third year using this deck.
I have never run the deck without the mulching kit installed, and I have never used the comparably sized Ventrac side-discharge mower deck. So, I have had no way to compare the size of the clippings ejected by the side-discharge deck to the size of the clippings ejected by my rear-discharge deck.
That said, I can tell you that the clippings ejected by my rear-discharge deck are pretty small. I use the deck not only to cut grass during the growing season but also to shred leaves in the Fall. (Our property is heavily wooded, mostly with oaks, so we get a lot of leaves in the Fall.) The leaf shreds are much smaller than the original leaves themselves. The size of the shreds depends somewhat on the types of leaves and how dry they are.
I have not had a huge problem with material clogging up the particulate screen that sits behind the radiator. In fact, the bar-graph temperature display on the instrument cluster has never gone above the second bar. Most of the time, when I am mowing, only the first bar glows, and even that bar will extinguish pretty quickly after I disengage the PTO and idle the engine prior to shutting the engine off.
How much material will build up on the particulate screen seems to depend most heavily upon how dry the grass or leaves are when I am mowing or shredding.
