It I add the proper amount of 100% to a water-filled cooling system, will it mix quickly to 50/50 inside the engine?
1 Like
How did your car get to 100% water concentration in cooling system?
How are you going to add water to a âfilledâ cooling system?
1 Like
Do you mean that you will pour enough water to fill the cooling system to 50% and then top off with antifreeze?
Time for a test!
- Drain the coolant in the system completely. Remember to remove the engine plugs so that all the coolant is drained.
- Measure the amount of water you use to fill an empty cooling system to 50%. Did you remember to replace the engine plugs?
- Add the same amount of antifreeze concentrate to the cooling system.
- If the cooling system is not filled, add water and then antifreeze in equal amounts until you can use your hydrometer to test concentration. Run the truck for a few minutes, shut off the truck, and wait until the radiator is cool enough to take the radiator cap off.
- Measure coolant concentration. If itâs not 50% rerun the test until it is 50%, verified by getting two consecutive identical readings.
1 Like
Another âinterestingâ George question. No way to add anything to a water-filled system, as others have said. And putting it in the overflow wouldnât work, either. If you wanted to ask 'if I put in one gallon of water followed by one gallon of 100% antifreeze to a two-gallon system, will it mix quickly?", my answer is yes, run it a few minutes after warm up and youâll be mixed.
4 Likes
Working on the vehicle that had been sitting for 5 years, and that had blown the trans cooler and you installed a new rad and had to drain it a few times for various reasons while dealing with multiple issues including the trans that had coolant mixed in the ATF, didnât want to waste money on coolant until you new you werenât gonna junk it, so you put straight water in it and drive awhile to make sure everything is working as it should⊠Then when the temp drops down below freezing, you have to take the good car out of the garage and put the other one in so it doesnât freeze⊠
Short answer, it will mix eventually. I would drain as much water out as I could and measure the amount that drained. Compare that to the coolant capacity listed in the owners manual to get an idea of the amount of water left in the system.
Then Iâd take half (or slightly more than half) of the cooling system capacity and use that much antifreeze concentrate into empty containers. Then add the needed amount of water to fill the system. Mix that in the containers and then fill the cooling system. Little more work but I think worth it.
The engine has tro have already been flusher with with water. dain as much as you can. Fill with half i=of the capacity of coolant and fill with water. Put a 50/50 mix in the overflow tank and drive normally topping with water in the radiator until it wonât take any more. Donât do his in subzero weather unless you have a somewhat heated garafe.
But donât do it today: itâs the 13th.
1 Like
Say it holds 8 quarts of 50/50 mix, old coolant I want to remove and refill with a fresh 50/50 mix . I drain 5 quarts, b/c thatâs all thatâs possible to drain from the radiator. Then i flush the remaining 3 quarts of old coolant out by filling w/water, idle the engine for a while, then draining, repeat several times. Eventually I end up with 100% water. I want to end up with a 50/50 mix. So I again drain 5 quarts, leaving 3 quarts of water. I add 4 quarts of 100%, and 1 quart of water. How much driving will it take to mix throughly to 50/50? I donât want to have any pockets of plain water which might corrode the engine innards, or worse, freeze and burst the engine.
One podcast mechanic (pro) says this wonât work, at least on certain cars, it wonât mix.
Nonsense. Water mixes easily and quickly with coolant, it would have to be totally isolated from the cooling system not to mix after a few minutes with the thermostat open.
It will take about 60 seconds to mix the coolant inside the engine, about 4 miles to mix the coolant in the radiator and engine.
Start the engine with the heater hoses disconnected, you will see how effective the water pump moves coolant.
You have replaced the coolant in your truck 22 times in the past, now you are concerned about procedure?
1 Like
Should I simply ignore the claim by a pro mechanic that coolant and water donât mix properly inside the engine?
It it were me. Iâd just remove the drain plugs from both sides of engine block after draining the radiator.
And after closing things back up, refill the cooling system with a 50/50 mix of coolant.
Tester
Iâve tried to remove the Corollaâs drain plug. Easy to access, but very stubborn, refuses to budge with the typical amount of torque I use on ordinary fasteners. . If I apply too much force it might damage the block, a step in the wrong direction. . But you are right , that would do the job.
Thatâs probably right ⊠lol ⊠.
Did you try hitting it with your purse?
Tester
I donât think that would work. But Iâll give it a try next time Iâm under the car and have a purse nearby.
Absolutely-thatâs nonsense. Automobile water pumps put out tens of gallons per minute, plenty enough to mix thoroughly in a few minutes.
2 Likes
If the outdoor temperature is below zero you should premix the coolant as a precaution.