I'm replacing the old antifreeze/coolant but without an engine drain plug wasn't sure how to get all the old mix out. According to the book the total cooling capacity is 7ltrs with recommended 50/50 ethylene glycol antifreeze/coolant. I remove the radiator drain plug but only
3.5ltrs comes out so I assume half of the old mix is still left in the engine block.To get the old stuff out do I drain the radiator and fill it up with plain water and let the engine run to circulate the old mix from the engine block into the radiator and then keep draining & filling up with plain water until I see no more old antifreeze mix entering the expansion tank?