Coolant question

4.0TJOwner

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Hello, so I flushed my cooling system with thermocure for 3 days and then I have been running around 12 to 15 gallons of distilled water over several days, today I will take out the last of the water that is left in the system but I won't really open it the block bleed screw, can someone tell me how much pure coolant to add and how to mix it using the water that is already in my car so that the coolant mixture is not so bad.
 
Maybe this will help?

https://wranglertjforum.com/threads/jeep-wrangler-tj-cooling-system-overhaul-faq.3397/

If you're not pulling the block drain then I'd pull the radiator drain and pull out as much distilled water as you can...then I'd add a 75 antifreeze 25 percent distilled water mix in...get it warm enough to open the thermostat and circulate for a while...then test the coolant mix with a float gauge... possibly drain more or add pure antifreeze to fine tune the mix.

-Mac
 
Maybe this will help?

https://wranglertjforum.com/threads/jeep-wrangler-tj-cooling-system-overhaul-faq.3397/

If you're not pulling the block drain then I'd pull the radiator drain and pull out as much distilled water as you can...then I'd add a 75 antifreeze 25 percent distilled water mix in...get it warm enough to open the thermostat and circulate for a while...then test the coolant mix with a float gauge... possibly drain more or add pure antifreeze to fine tune the mix.

-Mac

I looked at this post a few months ago and I did everything indicated, I changed the thermostat and drilled 1/8 on it, I replaced the old radiator and did thermocure before putting in a new one so that all the garbage would remain in the old one, today I will drain the last batch of distilled water from the radiator and I will put in the mixture that you recommend. I hope today to get very clear water from that radiator before putting in the coolant and forgetting about it for a while.
 
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IIRC, the block holds just shy of 1 gal of coolant.

Total capacity is 10.5 quarts. So...math...to get 50/50 you'd need basically 5 quarts of coolant and 5 of distilled water. You've got 4 distilled in the block. So one quart of distilled water and 5 of coolant would be perfect...but I'd still check with a float gauge.

Basically 85 percent not 75.

-Mac
 
As said previously figure out total system capacity, add amount of coolant for 50/50 and fill the rest with DW. Mix 50/50 and fill overflow.
Ezy-Pezy.
 
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Total capacity is 10.5 quarts. So...math...to get 50/50 you'd need basically 5 quarts of coolant and 5 of distilled water. You've got 4 distilled in the block. So one quart of distilled water and 5 of coolant would be perfect...but I'd still check with a float gauge.

Basically 85 percent not 75.

-Mac

Is there a way to check if the mixture has too much coolant with the tester? or only if it lacks purity?
 
Total capacity is 10.5 quarts. So...math...to get 50/50 you'd need basically 5 quarts of coolant and 5 of distilled water. You've got 4 distilled in the block. So one quart of distilled water and 5 of coolant would be perfect...but I'd still check with a float gauge.

Basically 85 percent not 75.

-Mac
So I make a mixture of 85 percent coolant, pour it in and do the test? as simple as this? Yesterday when I drained the radiator I got a total of around 6 quarts or less if I'm not mistaken, today I may get a little more when I remove the water, because it is raised at the back a little to facilitate extraction through the radiator.
 
IMG20240607124923.webp
 
Don't overthink it. You live in Miami. Nothing is going to freeze if it's not exactly a 50/50 mixture. 🤫 I use a chemical flush and change my antifreeze every three years on my Jeeps. I fill it with a 50/50 mixture and don't worry about what's left in the block, unless it's rust.
 
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Don't overthink it. You live in Miami. Nothing is going to freeze if it's not exactly a 50/50 mixture. 🤫 I use a chemical flush and change my antifreeze every three years on my Jeeps. I fill it with a 50/50 mixture and don't worry about what's left in the block, unless it's rust.

I understand, I just thought that a correct mixture also increases the boiling point, It's hot as hell here these days.
 
50/50 mix is more to achieve better corrosion resistance than freeze protection.

Completely agree with @TheBoogieman but you never know when the North Atlantic current will collapse.

-Mac

At this time I made the mixture, tomorrow I will go to Walmart for a test to see how it goes, although I think I added more coolant than water lol
 
I also assume there's about 1 gallon of water left in the system, maybe less.
I buy 2 gallons of concentrated and 1 gallon of distilled water.
Pour 1 in the radiator.
Use the other one to make 2 more gallons of 50/50.
Filling the rest with this will make everything close enough. ;)
 
I also assume there's about 1 gallon of water left in the system, maybe less.
I buy 2 gallons of concentrated and 1 gallon of distilled water.
Pour 1 in the radiator.
Use the other one to make 2 more gallons of 50/50.
Filling the rest with this will make everything close enough. ;)

I think there was less than a gallon left in the block, either way I made a mixture of more coolant than water. I'll do a test tomorrow to see how it goes but it worked perfectly today after removing all the bubbles.