What are the common methods to winterize a water pump such as on a pressure washer or Lesco sprayer? I might be purchasing a nice used sprayer soon but am concerned about freezing up the pump before next season. I was wondering if I put RV water line antifreeze in it, would that be the best bet? It's non-toxic and safe enough for the water lines in our camper so I figure it would be safe for the internal parts of a pump. Thanks.