I have always used tap water, just convenient. If you think about the amount of minerals or whatever in just a gallon or two of water, it's really nothing compared to a faucet or appliance that sees flowing water regularly. Years ago I read an article that stated not to use distilled water in place of tap water in cooling systems. May have been a crazy author, and I have never found that article again or anything else supporting that. Wish I could remember the reason, been too long ago.
Can I use tap water for initial flushing???
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I've done this many times. I even used to have my Comet 289 V8 running, with a hose pouring water into the radiator and the drain draining, but I don't think I'd do that anymore. Too easy to get it wrong and overheat the engine - though it always worked out fine.
One tip - You don't know how much water is going to be left behind when you do your final drain, but there will be some. So, knowing the cooling system volume, pour in the required amount of pure antifreeze to get to a final 50:50 mix and top up with as much distilled water as needed. Then add distilled water over the first few days as the system burps itself.
One tip - You don't know how much water is going to be left behind when you do your final drain, but there will be some. So, knowing the cooling system volume, pour in the required amount of pure antifreeze to get to a final 50:50 mix and top up with as much distilled water as needed. Then add distilled water over the first few days as the system burps itself.
The tap water where i live is very high in quicklime, but have flushed my cars many times with no issues, just be sure to get the correct antifreeze/ water mix you want in the end.
Our taps are surface water...not too hard, but some nonetheless....coolant...some of ya'll are going to cringe when I way this, but probably go with Supertech....reason....face it, the truck is 17 years old. I'm looking at probably getting rid of it within the next 2 years. Starting to show signs of age and with that comes problems. But, the price difference between supertech and prestone isn't really that much, something like 50-ish cents or so when I was at wallyworld looking around....10.85 a gallon of undiluted Prestone. I'm going back with the "green"...that's what was in it. At that time, Ford hadn't switched over to the orange stuff yet for that particular model.
Some say flush with tap, then distilled. Even with the hardest water, have you ever thought about how thick of a layer of calcium would be deposited doing one fill with tap? I cannot imagine it would be more than maybe .001-.002" thick. Do you? There just is not THAT much minerals available to be that much. It's a none issue unless you are doing constant changes of coolant (which is an un-necessary waste of time and resources).
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Originally Posted By: philipp10
Some say flush with tap, then distilled. Even with the hardest water, have you ever thought about how thick of a layer of calcium would be deposited doing one fill with tap? I cannot imagine it would be more than maybe .001-.002" thick. Do you? There just is not THAT much minerals available to be that much. It's a none issue unless you are doing constant changes of coolant (which is an un-necessary waste of time and resources).
I am more concerned that the extremely hard water that some of us have would not play well with the chemistry of the coolant, which is designed to be mixed with distilled or deionized water. Maybe a chemist can chime in. How do hard water chemicals like calcium, magnesium, iron, etc. affect the ability of coolant solution to protect engine metals?
Some say flush with tap, then distilled. Even with the hardest water, have you ever thought about how thick of a layer of calcium would be deposited doing one fill with tap? I cannot imagine it would be more than maybe .001-.002" thick. Do you? There just is not THAT much minerals available to be that much. It's a none issue unless you are doing constant changes of coolant (which is an un-necessary waste of time and resources).
I am more concerned that the extremely hard water that some of us have would not play well with the chemistry of the coolant, which is designed to be mixed with distilled or deionized water. Maybe a chemist can chime in. How do hard water chemicals like calcium, magnesium, iron, etc. affect the ability of coolant solution to protect engine metals?
I always flush with running water similar to using one of the Tee's in the heater hose. I usually take a heater hose loose and connect the water hose to it, run the engine and let it flush out of the open side of the heater hose. It is best to remove the thermostat and on some systems the radiator may need to be flushed separately.
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