Originally Posted by tjbiker031
Im sorry. this statement is wrong.
When flush with the hose, you will leave that water in the block and in the system. When you go to put the new coolant in with that non distilled water you will develop scale in the system essentially corroding the system. May not happen immediately, but it will. i can promise you that.
IF you are in a senario where you must flush with a garden hose, you must cycle (run to operational temp) with distilled water 2-4 times to ensure you get most of the water diluted with distilled water.
Most people dont realize that anything but distilled water can essentially destroy part or all of your cooling system. Same thing goes with mixing different types of coolant or using the wrong coolant.
I guess your automotive school doesn't stress on reading everything fully. In my post I state to make sure all tap water is completely drained.