Hello guys, I have a nit picky possibly over thinking question. First of all I live up in Northern usa where I see negative Temps in the winter and 95 degree Summer days. My concern and question is, when i am flushing my coolant system with water, and I drain all of the water I flushed my system with from the radiator to prepare my final stage of the process of adding my 50/50 mix of coolant, how do I know that I got all of the straight water out of the system in the first place ??? Something tells me I'll never be able to get all that straight water out of my coolant system... so this means my coolant mixture will inevitably be less than 50/50 mix, which is not good for me when it's -15 degrees outside... those of you who have done flushes, how the heck do you know you got all the water out? How do you compensate?
Coolant flush question
- Thread starter Pucks18
- Start date
I use concentrate. Then it’s ezpz.
I look up the specs on the volume of the system (available for all cars). If it’s, say, 10qts:
- I then multiply by my desired final ratio (I use 60%) - so 6qts.
- I add 6qts to the system
- top up with distilled water.
If you do not use concentrate, you will have to be content with less than 50/50, as you are going to have up to 20% of the system still with water in it (heater core, low pointes, etc) when you start adding the pre-mix.
My brother lived in Northern IL a while, and I’ve seen -30F there when visiting him. I would not run even 50/50 there myself - I’d mix it 60/40. it buys a LOT more protection - 20% more additives for one thing, plus freeze protection down to -55F.
I look up the specs on the volume of the system (available for all cars). If it’s, say, 10qts:
- I then multiply by my desired final ratio (I use 60%) - so 6qts.
- I add 6qts to the system
- top up with distilled water.
If you do not use concentrate, you will have to be content with less than 50/50, as you are going to have up to 20% of the system still with water in it (heater core, low pointes, etc) when you start adding the pre-mix.
My brother lived in Northern IL a while, and I’ve seen -30F there when visiting him. I would not run even 50/50 there myself - I’d mix it 60/40. it buys a LOT more protection - 20% more additives for one thing, plus freeze protection down to -55F.
What Oro-O said. Also, if you can't get a concentrate version of the coolant you want to use, then just stick with a drain and fill.
To get the maximum amount out of the system, pull the bottom house off the radiator and start the engine briefly. It may make a mess but the water pump will push more out than just draining it alone.
To get the maximum amount out of the system, pull the bottom house off the radiator and start the engine briefly. It may make a mess but the water pump will push more out than just draining it alone.
Get one of these and test your coolant freeze point. If it's too low drain some out of the radiator and top up with 100% concentrate.
https://store.autovalueparts.ca/en/p/prestone/70795/antifreeze-coolant-tester/100159681
https://store.autovalueparts.ca/en/p/prestone/70795/antifreeze-coolant-tester/100159681
Correct, you will not get all the water out. When you add the coolant, fill the entire rad with 100% coolant. Never add just a 50/50 mixture if you have water alone in the block. One other thing you can do if you are looking for a 50/50 final concentration is to sacrifice some fresh coolant by filling the rad with 50/50, circulating it though the engine and dumping it (you can save it in a jug if you like. Then, fill the rad with 100% coolant. This typically will get you there if your rad volume is is about a third of your block and hose volume. Use a refractometer or even a cheap anti freeze tester to check your concentration.
All correct except in a 10 quart system the rad will probably hold about 1/3 or 3.3 quarts, so folks scratch their heads on how are they going to load six quarts into the engine when the rad only holds 3.3 quarts. With mostly fresh water in the system, I’ll fill the rad with 100% coolant, drive the vehicle then drain the the rad of 3.3 gallons of diluted fluid that contains 6.3 water and 3.3 coolant again. Then, I’ll fill the rad with 3.3 gallons of 100% coolant again. None of this stuff requires measurement. Just completely fill the rad and coolant jug each time
In real life most people are not successful in getting all the original coolant out unless they buy a flush T kit that used to be common years ago.
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Fk. Well I have concentrated toyota red coolant. I can think of a easy and simple way to make a 60/40 percent mixture. 50/50 is so **** easy to do on a large scale, but 60/40 sounds like a pita
So how’s this?
1. Drain your rad.
2. Fill with distilled water.
3. Go for a drive.
4. Drain your rad a second time.
5. Fill with 50/50 water/antifreeze.
6. Go for a drive.
6. Drain your rad a third time.
7. Fill with 100% antifreeze. You are done.
There you go and Bob’s your Uncle.
1. Drain your rad.
2. Fill with distilled water.
3. Go for a drive.
4. Drain your rad a second time.
5. Fill with 50/50 water/antifreeze.
6. Go for a drive.
6. Drain your rad a third time.
7. Fill with 100% antifreeze. You are done.
There you go and Bob’s your Uncle.
Sounds like a terrible idea no offenseSo how’s this?
1. Drain your rad.
2. Fill with distilled water.
3. Go for a drive.
4. Drain your rad a second time.
5. Fill with 50/50 water/antifreeze.
6. Go for a drive.
6. Drain your rad a third time.
7. Fill with 100% antifreeze. You are done.
There you go and Bob’s your Uncle.
Instead of step 7, find the total coolant capacity in the owners manual. Then multiply to find the amount of coolant needed. For instance, if you want a 60% mixture and you car takes 9 quarts, it would be 9 x .6 = 5.4 quarts. So add 5.4 quarts and then top off the rest with additional water.
I'm reading online forums of dudes way up in Canada who say they all use 50/50 coolant mixture. It has been over -29 degrees real temp in the Chicago land area in 30 years, and 50/50 covers around -35 to -40. I'm just going to do drain and fills of 50/50
Ok, let’s hear your plan to load 5.4 quarts into and engine with a rad volume of 3.3 quarts. The block will be full of water. I think you mentioned in posting number 3 starting the engine with the lower hose off. That hose is the suction side of the pump. I’m not sure what would happen but if it worked for you great.
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Yup. Good enough for Chicago.
Just buy 100% concentrate antifreeze and a big bottle of distilled water and mix the to the ratio you want in a 5 gallon pail. It's cheaper to do it like this then buying 50/50. And just buy a cheap tester to see what your freezing point in about one week after you did the drain and fill.
You're right that not every car is the same. I find that if I start the engine for a few moments with the lower hose off I get more coolant out of the block. I can't remember ever not getting to 50/50 doing it that way. Don't forget you've also got another quart or two of capacity in the overflow bottle that is included in the total capacity listed in the manual.
This is by far the best and easiest way. You may waste a bit of antifreeze by draining off some, then refilling with 100% concentrate. But overall it's the easiest and least messy. And it will also allow to achieve the best concentration you're looking for.
You could always flush with new 50/50, otherwise, unless your block has drain plugs then you will not be able to get the distilled water out of the block. You can either flush with distilled water then fill the radiator with concentrate(and check/adjust the mix after a full warm up cycle), do a drain and fill with 50/50, or flush with 50/50.
Don't over think it. If it's really bothering you Just buy the concentrate, mix 55/45 or 60/40 yourself and call it a day.
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Have you pulled the drain plug(s) in the block? If not then you have not gotten all the water out from the flush. Also would need to disconnect the heater core hoses at both ends and use compressed air to remove the water in it.
And was your last round of flushes using garden hose water or distilled water?
Most people doing a complete flush will use concentrate and gallons of distilled water.
Unless you drain everything, mix at 60/40 and you will probably end up close to 50/50.
Check final mix with antifreeze tester.
