The wand and the spray tip are left attached for this process to provide a back pressure that will help expel 90% of the unused material out of the unit. 2) Then circulate either soap and water or other recommended cleaning solution through the unit until it comes out clean and clear. NEVER USE STRAIGHT XYLENE. Soap and water or diesel are best. 3) Drain all liquid from the pump. Do NOT allow liquid to freeze in the pump. Failure to do this will result in damage to the internal components of the