Coolant System Flush Question.

[Carder09]

Well I have completely drained the coolant, I think, flushed it twice, replaced some critical hoses, and filled her up, only thing is im not sure if I still left some regular water in the block or radiator, I blew out water from the system or water pump maybe, didn't open the plugs on the block though, so since it only took about a gallon in a half, needs 16.7 quarts, im guessing there is still regular water or more water in the system than coolant, so should I disconnect the lower rad hose and let the part water part coolant leak out and add continuously to completely flush system with coolant or what?

[Carder09]

Nevermind, I "flushed" the system once more but with coolant mix and everything is runnin perfect so I guess it worked for now lol

[AzDragonLord]

[Chevrolet1]

To help prevent straight water from staying in the system, I simply drain mine in all places possible (e.g. lower radiator hose, heater hoses, radiator drain cock, etc.). Then I use my shop vac on multiple hoses to extract whatever else I can and thoroughly clean the overflow bottle. Measure how much was removed in total so you know how much to put back in (and you won't be low). Mix distilled water and DexCool in your preferred ratio (e.g. 50/50 to 30/70, respectively) and pour it back in per the owner's manual. This way you never introduce water with hard minerals into your system. Any old coolant/water mixture still in the system will be very diluted and should pose no issue for the next 5 years or 150K miles. My $0.02.