Coolant Boiling Question
#27
Not much experience with car engines, but I have had experience with water cooled computers and the exact same arguments come up and discussed at great length.
Ultimately, this is what I've taken away from the whole thing.
Pure water with a surfacent such as water wetter will give you the greatest thermal efficiency, but gives you no corrosion protection. This is especially bad in systems where you have different types of metal such as copper and aluminum in contact with the coolant. You might be better off at first, but when your radiator rots out, you're in for some trouble.
50/50 antifreeze water mix cannot transfer heat quite as quickly, but will keep dissimilar metals from reacting with each other and corroding. It also prevents the coolant from freezing.
Pure antifreeze = you fail at life.
I'm a bit hazy on boiling points for things, as computer coolant cant reach that temp, but if you are thinking about changing your coolant to improve performance, you'd be better off upgrading your radiator, as the difference between coolants is a few percent difference, but an upgraded radiator could get much larger gains in cooling efficiency.
Ultimately, this is what I've taken away from the whole thing.
Pure water with a surfacent such as water wetter will give you the greatest thermal efficiency, but gives you no corrosion protection. This is especially bad in systems where you have different types of metal such as copper and aluminum in contact with the coolant. You might be better off at first, but when your radiator rots out, you're in for some trouble.
50/50 antifreeze water mix cannot transfer heat quite as quickly, but will keep dissimilar metals from reacting with each other and corroding. It also prevents the coolant from freezing.
Pure antifreeze = you fail at life.
I'm a bit hazy on boiling points for things, as computer coolant cant reach that temp, but if you are thinking about changing your coolant to improve performance, you'd be better off upgrading your radiator, as the difference between coolants is a few percent difference, but an upgraded radiator could get much larger gains in cooling efficiency.
Last edited by Socket7; 08-21-2007 at 06:36 PM.
#28
are you high?
coolant/anti-freeze is designed to keep engine temps down, and to resist freezing. its an additive that raises the boiling point and lowers the freezing point...
#29
I'm a bit hazy on boiling points for things, as computer coolant cant reach that temp, but if you are thinking about changing your coolant to improve performance, you'd be better off upgrading your radiator, as the difference between coolants is a few percent difference, but an upgraded radiator could get much larger gains in cooling efficiency.
So we're not as worried about bugs and crap growing in there. But yeah, if you need more cooling, a radiator upgrade would also help.
You haven't been paying attention. Your radiator is pressurized, Why would you care that your coolant can reach 300F? Your car would already be destroyed before that point. As long as your car is operating normally, you'll be fine with straight water. It's boiling point is higher than you seem to think.
Last edited by mysql101; 08-21-2007 at 06:40 PM.
#32
That's it folks, I'm tired of repeating myself!
#33
I guess it doesn't make sense to you, because you have issues with reading comprehension.
Read my post again:
https://www.rx8club.com/showpost.php...86&postcount=2
Not only are the numbers you quoted different, but your conclusion is reversed.
They put a car on a dyno, ran it for 3 hours at 7,000 rpm, and calculated the resulting temp.
Regular 50/50 mix coolant came out to 228F. Water with water wetter came out to 202F (I consider the number with 100% just water invalid for real world use since you can't run your car that way).
Raising the boiling point of water is going to be useless for the most part. Your car shouldn't reach temps that high if it's functioning normally. Remember, the system is pressurized, so it's not like boiling a pot of water on the stove. 220F isn't going to boil it.
Read my post again:
https://www.rx8club.com/showpost.php...86&postcount=2
Not only are the numbers you quoted different, but your conclusion is reversed.
They put a car on a dyno, ran it for 3 hours at 7,000 rpm, and calculated the resulting temp.
Regular 50/50 mix coolant came out to 228F. Water with water wetter came out to 202F (I consider the number with 100% just water invalid for real world use since you can't run your car that way).
Raising the boiling point of water is going to be useless for the most part. Your car shouldn't reach temps that high if it's functioning normally. Remember, the system is pressurized, so it's not like boiling a pot of water on the stove. 220F isn't going to boil it.
#34
Has anyone here ever even taken a look at the back of an anti-freeze/coolant bottle? There have been some very valid points made here, but there is a reason why cars leave the factory with a water and antifreeze/coolant mix. It has been stated several times here that water mixed with antifreeze/coolant will provide a higher boiling point and lower freezing point than with water alone or antifreeze/coolant alone. I will also stand behind that. Antifreeze/coolant is not a substitute for water, only and additive that increases its maximum boiling point and loweres its freezing point. It isn't a hard thing to understand.
#35
You are wrong....pure water cools better than coolant.....look at the data...there is lots of it around.
EG is used to keep the coolant from freezing..and the additives protect the engine from corrosion and lubricate the water pump
If your "friends" think this is funny they are as malinformed as you.......
spout off on something that you actually know about.............
EG is used to keep the coolant from freezing..and the additives protect the engine from corrosion and lubricate the water pump
If your "friends" think this is funny they are as malinformed as you.......
spout off on something that you actually know about.............
First, malinformed isn't even a word - I believe you are looking for the word misinformed.
Secondly, not once did I ever say running pure coolant was the way to go. Antifreeze + Water changes the chemical properties of the liquid, and it's typically called "Engine Coolant". Why do you people refuse to see this?
Coolant absorbs heat from the block, flows through a radiator which blows outside air over cooling fins, which in turn take heat away from the coolant inside the radiator, which is pumped by a water pump, to keep a constant flow of new coolant going to your engine. This is not new technology.
#36
The devil made me do it
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And what is the efficiency of said device? As my engine temps climb does it instantly bring my coolant temp back down? And I could probably dig around and find all sorts of information but I am lazy...but doesn't normal thermostats open around 180? Why would I want to only give myself 20 degrees to work with before producing oxygen? I may never hit 265+, but I like my odds of getting close to 265 better than 202.
#37
Holy crap Batman we have a winner....
First, malinformed isn't even a word - I believe you are looking for the word misinformed.
Secondly, not once did I ever say running pure coolant was the way to go. Antifreeze + Water changes the chemical properties of the liquid, and it's typically called "Engine Coolant". Why do you people refuse to see this?
Coolant absorbs heat from the block, flows through a radiator which blows outside air over cooling fins, which in turn take heat away from the coolant inside the radiator, which is pumped by a water pump, to keep a constant flow of new coolant going to your engine. This is not new technology.
First, malinformed isn't even a word - I believe you are looking for the word misinformed.
Secondly, not once did I ever say running pure coolant was the way to go. Antifreeze + Water changes the chemical properties of the liquid, and it's typically called "Engine Coolant". Why do you people refuse to see this?
Coolant absorbs heat from the block, flows through a radiator which blows outside air over cooling fins, which in turn take heat away from the coolant inside the radiator, which is pumped by a water pump, to keep a constant flow of new coolant going to your engine. This is not new technology.
#41
All Mighty Wikipedia says, and I quote:
"The most common coolant is water. Its high heat capacity and low cost makes it a suitable heat-transfer medium. It is usually used with additives, like corrosion inhibitors and antifreezes. Antifreeze, a solution of a suitable organic chemical (most often ethylene glycol, diethylene glycol, or propylene glycol) in water, is used when the water-based coolant has to withstand temperatures below 0 °C, or when its boiling point has to be raised."
#42
The devil made me do it
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We are not saying that water can not be used Moe. What we have been trying to say is that lowering the boiling point is not a good idea. Water Wetter according to mysql's post drops the boiling point from 220 to 202 making it more prone to boiling and or inefficient cooling.
#43
John, read the bold text. I never said that you should only use water.
I'm all for engine coolant, I would never put just water in my car, and I definitely would never use any chemical that would lower my BP.
I need that extra protection, for when I race a grey Dodge Charger (wannabe Chrysler 300) on the highway when I leave work!
I'm all for engine coolant, I would never put just water in my car, and I definitely would never use any chemical that would lower my BP.
I need that extra protection, for when I race a grey Dodge Charger (wannabe Chrysler 300) on the highway when I leave work!
Last edited by Da1MoeD; 08-21-2007 at 07:25 PM.
#44
Coolant absorbs heat from the block, flows through a radiator which blows outside air over cooling fins, which in turn take heat away from the coolant inside the radiator, which is pumped by a water pump, to keep a constant flow of new coolant going to your engine. This is not new technology.
Are you still with me?
Okay so antifreeze is added to do two things. Most obvious is to lower the freezing point of the mixture. What it does in general is to expand the liquid range so in addition to the freezing point being lowered, the boiling point is raised. The second thing is to provide lubrication and corrosion protection to the cooling system.
Summarizing the above. Adding antifreeze:
Positive:
1) Lower freezing/higher boing point
2) Water pump lubrication and corrosion protection
Negative:
1) Lower heat capacity that pure water
Are you still with me?
Okay so now suppose you live somewhere where it never gets cold enough for freezing to be a problem. Then the lower freezing point is worthless.
Secondly the coolant system is sufficiantly pressurized to prevent boiling. Thus the higher boiling point of water/antifreeze mixture also becomes a non issue. So the only thing to be gained from adding antifreeze is the pump lubrication and corrosion protection. Both of these can be satisfied with a bottle of WaterWetter added to pure water.
#45
We are not saying that water can not be used Moe. What we have been trying to say is that lowering the boiling point is not a good idea. Water Wetter according to mysql's post drops the boiling point from 220 to 202 making it more prone to boiling and or inefficient cooling.
If you read my post, it never said anything about boiling point. Hell, logic says 50/50 coolant doesn't boil at 220, and pure water isn't going to boil in your radiator at 202.
What the test showed, was a comparison of 50/50 vs water + additive. The same car, the same drive (3 hours at 7000 rpm), and the coolant temp was almost 20F cooler. TEMP OF THE LIQUID, not it's boiling point.
As I said before, unless your radiator fans are broken, running with just water is fine since you're not going to hit the boiling point. Furthermore, because water is more efficient, your radiator will be able to extract the heat from the radiator far quicker than you would be able to with 50/50 of coolant. So that brings me back to what I said before - the higher boiling point of 50/50 doesn't mean squat since you're not going to be hitting it.
This is simple stuff people. What's so difficult to understand?
#49
They also showed that with a 15 PSI radiator cap, the 50/50 mix only had a 15F higher boiling temp.
So your choice is to either heat soak your engine, and have a higher boiling temp (only marginally so), or run with water where you can be almost 20F cooler to begin with, AND be able to pull the heat out of the radiator quicker ... so in stop and go traffic, your temps will drop faster.
It's a no brainer! (Assuming you live where it doesn't freeze - or you can change coolant with the seasons).
#50
The devil made me do it
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I wasn't going to post anymore here, but I can't leave this without an answer.
If you read my post, it never said anything about boiling point. Hell, logic says 50/50 coolant doesn't boil at 220, and pure water isn't going to boil in your radiator at 202.
What the test showed, was a comparison of 50/50 vs water + additive. The same car, the same drive (3 hours at 7000 rpm), and the coolant temp was almost 20F cooler. TEMP OF THE LIQUID, not it's boiling point.
If you read my post, it never said anything about boiling point. Hell, logic says 50/50 coolant doesn't boil at 220, and pure water isn't going to boil in your radiator at 202.
What the test showed, was a comparison of 50/50 vs water + additive. The same car, the same drive (3 hours at 7000 rpm), and the coolant temp was almost 20F cooler. TEMP OF THE LIQUID, not it's boiling point.
As I said before, unless your radiator fans are broken, running with just water is fine since you're not going to hit the boiling point. Furthermore, because water is more efficient, your radiator will be able to extract the heat from the radiator far quicker than you would be able to with 50/50 of coolant. So that brings me back to what I said before - the higher boiling point of 50/50 doesn't mean squat since you're not going to be hitting it.
This is simple stuff people. What's so difficult to understand?
This is simple stuff people. What's so difficult to understand?