Of course, the problem is the "mayonnaise emulsified oil" still in the hoses, filters, pump, and cylinders. You can dry out the tank with warm air flow, but as soon as the wet oil returns to the sump, you've got water again, but at a lower saturation level. Drain a couple times after using it so that the oil gets hot. Then you are somewhat dependent upon the hot oil eventually gassing off the water remaining in the system, but you just have to get the moisture level down low enough so that the moisture saturated oil does not affect the operating properties of the oil. Water and oil do not like to stay mixed, so as long as the entrained moisture is low enough and not emulsified to not cause any operational problems, the heat of the oil will eventually drive it out. For the oil that you pull out on a 2nd flush, if it's barely used, you can probably let it sit with a vent in the cap, and the water should eventually gas off if you leave the container in the sun for a awhile, and if you wanted to get fancy and have a vacuum pump on the farm, you could pull a vacuum on the oil which will cause the water to boil off and get pulled out of the oil as a vapor.