System is meant to be drained via the red drain plug on the lower nearside (passenger) of the radiator. It only unscrews partway, does not remove completely. Draining can also be done by removing the bottom hose - much quicker!
Only about half the coolant drains by this method, the remainder still in the engine block, heater matrix etc, hence recommendation to refill with fresh water and drain a few times to dilute the mix to (virtually) plain water.
Yes, you can speed up the process by having a hosepipe feeding clean water into the header tank at the rate it drains from the rad drain tap. Done that a couple of times myself....
When wanting to put in the antifreeze, drain the water out the rad, refill with neat antifreeze quantity, then top up with water. Start the engine, expansion cap off, and 'burp' air out the large upper radiator hose as the engine warms. Make sure the heater control in the car is on maximum hot. Top up water level as required. Replace expansion cap, let it cool overnight, and recheck the level in the morning. Again, top up as required.
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Topic: Changing engine coolent (Read 581 times)