Hi guys... For some time my car was running on water as it kept leaking coolant.. I got this leak sorted and four that the coolant tank had turned out to be brown and rusty colour. I then ran some water to flush the brown rusty water out of the car. After draining it I mixed g12 ++ 50/50 with water.. After running the car with a new coolant tank the coolant seems to have started to change brown rusty colour. Is the any mix that will flush the whole system to remove the rusty water... Also what is the best way to flush the rusty water completely out of the system.. Can anyone help?