I dont think it hurts the machine much,if you are sucking water up in the deck,it would be wise to grease all the bearings/fittings when done.My dixie chopper cuts as good wet as dry,no clumps at all,but it will plug up like every few minutes,unless i can find a deep puddle or low spot,drive over it and itll suck the water right out of the puddle and clean the deck,it does make a mess in the puddle though.