I watched 4 different youtube videos and I'm still not sure of how to flush a radiator. Some use a radiator flush chemical and some don't. Some use a pressure washer or garden hose to flush the block and some don't. Some use distilled water as a rinse of the chemical flush and some don't. And then there's the issue that unless you have a special machine you won't be able to drain the engine block which means you'll have to use concentrate to mix with the plain water in the engine block and then use a 50/50 mix to finish filling the cooling system. Most videos use only a 50/50 mix despite the engine block having close to a gallon (maybe more) of water in the engine block. My 02 Mustang GT has 14.1 quart capacity but when I drain the radiator I get less than 2 gallons in the drain pan. Obviously, there's still a lot of coolant left in the engine block and heater core. So, what is one to do?
I use compressed air at the thermostat mounting area to completely evacuate the block and heater core of all the plain water I flush the block with.
I'll probably have to do that. I can only drain 1.5 gallons out of the radiator which means I still have 2 gallons in the heater core and engine block (my car has 3.5 gallon capacity). But if I get all the old stuff out using distilled water, I would have to add 2 gallons of concentrate coolant to the radiator (which actually takes 1.5 gallons) to mix with the 2 gallons in the block and heater core to get a 50/50 mix (approximately) which means I won't need 50/50 coolant.. So, I won't follow the Chris Fix procedure exactly. If my procedure yields less than desirable results, I still have time to redo it before the cold weather hits.
So far, I rinsed my cooling system with 13 gallons of distilled water and it's still coming out muddy. Next time I'll just use tap water.