Some ya'll might remember that my truck started getting really hot coming back from a trip last month. Checked some things out like the mechanical fan, hoses, etc. etc. and everything seems fine. Truck sits a lot and has set a lot over the years so I'm going to do a Prestone radiator flush this weekend. However, that thing has a HUGE coolant reservoir. My question, truck is cool, and I drain the radiator, can I use plain ol' tap water to flush out the radiator a few times? Then add the Prestone stuff, fill it with tap again, run the truck like it says for a few hours, dump the radiator again. If it's still dirty, just keep doing a tap water fill, run, then dump until it gets clear....then add distilled water and antifreeze for the final fill? I know some of that tap water will be inside the block, and there is no way I can get to the block drain. Will or could that harm the system leaving some tap water in the block? I know years ago that's all we used, but things have changed.
Can I use tap water for initial flushing???
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Yeah it'll be fine, done that myself with my cars.
Can I use tap water for initial flushing???
Yes.
Yes.
Yes. Been using tap water for a long time with no problems.
Tap water should be fine as long as it's not super hard water. if you are using the Prestone flush kit don't you have to hook it up to a heater hose using the include T fitting and a garden hose anyway? On a side note my owners manual for the GTO states" ...50/50 mix of Dexcool and clear drinkable water"
Kestas
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Yes, that's how I do it... Give it a good flush with lots of tap water, then displace the tap water with distilled water before refilling.
My understanding is that regular tap water carries away contaminants much better than filtered water, when flushing. And a rinse with a good purified water(UF, DI, ROW, Distilled) prior to adding your coolant.
I know that some tap water contains various minerals and chlorine. However, in the 40 years I've been maintaining and racing cars and motorcycles, not once has a tap water flush caused any sort of problem.
I always use tap water, never had a problem. Distilled water is cheap these days ... newer filtration and purification technology helps there ... but it's never been a problem for me to not bother paying a couple of bucks and just go for the tap.
I suppose it depends on your local water quality; dissolved solids, especially irons and the salts used to treat home use water in some locations might take up some of a coolant's additive package prematurely. So there is that to consider, but if OK there I'd say have at 'er.
I suppose it depends on your local water quality; dissolved solids, especially irons and the salts used to treat home use water in some locations might take up some of a coolant's additive package prematurely. So there is that to consider, but if OK there I'd say have at 'er.
My shallow well's water is loaded with iron. I use for flushing AND mixing 50/50 with coolant. No issues.
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I use tap water in everything. Cars,iron,coffee maker,etc. Never had a single problem.
Originally Posted By: aquariuscsm
I use tap water in everything. Cars,iron,coffee maker,etc. Never had a single problem.
All tap water is not the same. When I lived in the City of Milwaukee the water from Lake Michigan had extremely low hardness, you could easily use it for all the uses you list above. There was virtually no reason to buy distilled water for anything.
But in the suburbs that use well water the hardness value is through the roof. If you use it to make coffee or in your iron it will clog up in short order. I delayed in putting in a water softener when we built our house and it took less than a year to ruin most of our faucets and appliances. I'd never use this water in an automotive cooling system under any circumstances.
I use tap water in everything. Cars,iron,coffee maker,etc. Never had a single problem.
All tap water is not the same. When I lived in the City of Milwaukee the water from Lake Michigan had extremely low hardness, you could easily use it for all the uses you list above. There was virtually no reason to buy distilled water for anything.
But in the suburbs that use well water the hardness value is through the roof. If you use it to make coffee or in your iron it will clog up in short order. I delayed in putting in a water softener when we built our house and it took less than a year to ruin most of our faucets and appliances. I'd never use this water in an automotive cooling system under any circumstances.
Keep in mind most municipal water supply's also have measurable amounts of antidepressants and tranquilizers. Your car should be chill and happy after the flush. 
Originally Posted By: Kawiguy454
Keep in mind most municipal water supply's also have measurable amounts of antidepressants and tranquilizers. Your car should be chill and happy after the flush.
Since Schmoe already has made a decision...if the municipal supply is from a river, his use of tap water might also cause some gender confusion for his vehicle:
https://fnfsr.org/hormone-lecture/
"Endocrine-disrupting chemicals have become common in rivers and streams and have been shown to affect fish as well as other aquatic life. (and vehicles) One such effect is “intersex,” the presence of both male and female characteristics within the same fish."
Keep in mind most municipal water supply's also have measurable amounts of antidepressants and tranquilizers. Your car should be chill and happy after the flush.
Since Schmoe already has made a decision...if the municipal supply is from a river, his use of tap water might also cause some gender confusion for his vehicle:
https://fnfsr.org/hormone-lecture/
I flush with tap water until the water comes out clean and clear. Then I do 2 fill / run / drains with distilled water. Then drain that and introduce my 50/50 Prestone and distilled water mix.
I use anything available from a garden hose then do 2 rinse outs with distilled.
My results are clear coolant.
My friends say it's not necessary. They're from municipalities and the country as well.
Their results are cloudy.
They say nothing is wrong. I say nothing.
I hope you're smarter than they are.
My results are clear coolant.
My friends say it's not necessary. They're from municipalities and the country as well.
Their results are cloudy.
They say nothing is wrong. I say nothing.
I hope you're smarter than they are.
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