Coolant Boiling Question
 

Okay, so as we all know water is more effective at removing heat from the engine than coolant or antifreeze. However, water also has a lower boiling point of 212 degrees and our thermostat opens in that temperature region. Since our cooling system is pressurized, I'm assuming the pressure is enough to keep the water liquid to a high enough temperature that if water does boil, the engine would be toast anyway. (Chemistry 101) Bubbles begin to form much earlier than the real boiling point though, so I'm wondering if there's an increased likelihood of small bubbles forming that will reduce cooling system efficiency when using pure water (plus an anti-corrosion agent) versus an actual coolant mix.

From the Water Wetter technical info PDF:

Dynomometer tests performed by Malcolm Garrett Racing Engines showed significant improvements in coolant temperatures using WaterWetter®. These tests were performed with a Chevrolet 350 V-8 with a cast iron block and aluminum cylinder heads. The thermostat temperature was 160°F. The engine oper- ated at 7200 rpm for three hours and the stabilized cooling system temperature was recorded and tabu- lated below:

50% Glycol / 50% water - 228F

50/50 with water wetter - 220F

Water - 220F

Water with water wetter - 202F




Red Line WaterWetter® does not significantly
increase the boiling point of water; however, increas-
ing pressure will raise the boiling point. The boiling
point of water treated with Red Line using a 15 psi
cap is 250°F compared to 265°F at 15 psi for 50%
glycol. Increasing the pressure by 50% to 23 psi will
increase the boiling point of water to 265°F. Because
of the doubling of the ability of the radiator to transfer
heat, boilover using Red Line treated water is not a
problem as long as the engine is circulating coolant
through the head and the fan is circulating air.
Sudden shutdown after very hard driving may cause
boilover.

We have a 9 bar radiator cap right? I calculated that at 9 bar the boiling point of straight water is 370 degrees F so real boilover isn't an issue. I'm more worried about localized areas where the coolant is starting to bubble.

i've been running around with distilled water + water wetter for a few weeks. No issues. I managed to get the coolant up to 210F a few times, but it cools down rapidly.

There's more to the story..

Except Evans coolant.

Dissolved air can effervesce from coolant, but to get steam bubbles you have to hit 212F.

Also note that nearly half or the rotary engine's cooling is done by the oil.

9 bar would explode the hoses & radiator.
You probably mean 9 PSI.

See Mysql101's post above..
-Bill

Yes I know about Evans. I considered running it for a little bit, but it's just too expensive for the perceived advantages for me.

I also thought 9 bar was a bit high since that's 8.8 atm or 130 psi, but 9 psi seems a bit low. I think the cap might be a 0.9 bar, which equates to around 13 psi. That seems more correct?

Are you people serious? Why don't you just throw some pasta in there too, and have a lovely dinner at the same time?

http://bioengr.ag.utk.edu/Extension/...es/engcool.htm

Read up about engine coolant.

Yeah, we're serious. Do you even know what coolant does? It doesn't cool.

edit: coolant above should read anti-freeze. Either way, coolant doesn't cool as well as water.

I hope you know that multiple car guys I work with are laughing at this thread.

So if coolant doesn't cool we are safe to run our cars without it then...yes? I mean...if it is just there too lube things like the water pump I can just save some cash and run pure air instead. Sounds like a plan! "Roger Roger...What's your vector Victor."

John, these people are experts in their field in Chemistry...look at their graduation picture:

http://upload.wikimedia.org/wikipedi...FoilHat002.jpg

The answer depends on where you live. If you're in an area where it might freeze, you'll need coolant, or your car can get messed up due to the water expanding when freezing. If you're in a location like FL where that rarely happens, you're going to be okay running pure distilled water.

The water pump needs lubrication though, which is why something like water wetter is good (in addition to breaking down the surface tension of the water).

Just so our terms are clearly defined - coolant generally means a mix of 50% water and 50% anti-freeze. The water part cools, the anti-freeze part prevents freezing of the water, and also expands the boiling temps - but at a cost. It doesn't cool as well as using pure water.

The lowered boiling point of using pure water with no anti-freeze generally isn't an issue. Your car isn't going to reach temps anywhere near that unless you're already having issues.

This is hilarious...what part of this doesn't make sense???????

Most of the antifreeze products on the market currently are ethylene glycol base material with additives to prevent corrosion, lubricate seals and water pumps and aid in heat transfer to the coolant from the metal of the engine. Antifreeze should be mixed with distilled water (tap water contains high amounts of minerals such as calcium and iron that can precipitate and coat internal parts) at the ratio of one part antifreeze to one part water. This gives freeze protection down to minus 34 degrees and boil-over protection up to +265 degrees. Never use pure antifreeze in a cooling system without using at least 30 percent water in the mixture. Most antifreeze products sold for the past several years have been the traditional "green" coolant. This type is good for two to three years and up to 30,000 miles. The green antifreeze contains silicates, phosphates and / or borates as corrosion inhibitors to keep the solution alkaline. As long as the solution remains alkaline, corrosion is controlled and the system is protected. Over time, the corrosion inhibitors will be depleted and the corrosion protection is lost. It is for this reason that green antifreeze should be changed every two years or so. Aluminum is especially vulnerable to corrosion and many vehicles have heads, radiators and other aluminum components in the cooling system. If the coolant in an engine cooling system is changed before corrosion inhibitors reach dangerously low levels, corrosion damage is prevented.

.9 bar

Lol, why cant you run only antifreeze?

The only thing hilarious about this is that you're spouting off to me about chemistry degrees, when you're the one who's in special ed.


Think about it. You can't use pure anti freeze without water. Care to guess why? Cause your car would overheat. So explain to me again about chemistry and how glycol magically helps cool better. Don't believe me? Look it up instead of posting silly photos.

Fact is, you don't know squat - and apparently either do your friends who are chuckling behind you. It takes twice as much ethylene glycol, and three times as much propylene glycol to cool compared to straight water.

As I said, antifreeze is useful to prevent your radiator and engine from cracking if you're in locations where freezing occurs. If you're not, then anti-freeze in your radiator is hindering far more than it will ever help.

You'll still need something to lubricate the water pump though. Water wetter to the rescue.

Antifreeze is an additive TO water which expands the max. boiling and freezing points...thats like asking why can't you just eat Kool-Aid powder??

So you're saying that anti-freeze cools better than water, and that anti-freeze is so concentrated that you need water to dilute it enough that it doesn't cool too much? I for one, am glad you're here to teach us about your magical dreamworld where facts and logic don't apply.

Just friggin' amazing.

Do you work for Redline or something?? Honest to God, I'm crying over here laughing at this....

It's not that complicated. As stated in the link I posted, as well as the last post I had, antifreeze is an additive TO water, and is used in conjunction with it to aid in the maximum boiling and cooling points of the liquid that is used to take heat away from your engine. Simple breakdown as in your second post:

Water - 220F

Water with water wetter - 202F

Water + Antifreeze = 265 + degrees

So where does anything your saying make any sense?

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.

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.............

hey, if you don't want water wetter, royal purple makes purple ice :)

Their numbers show similar results as redline's water wetter:

http://www.royalpurple.com/prodsa/prpice.html

A. Standard mix of water and glycol (antifreeze) - 228° F

B. 50 / 50 water / glycol mix with Purple Ice™ added - 222° F

C. Straight water (no corrosion protection) - 220° F

D. Water with Purple Ice™ added - 200° F


I feel for you, ProCharger GT. After spouting off like that, it's going to be hard to save face.

Wait, coolant actually comes as a powder? WOW!

MazdaManiac posted a link that showed that Royal Purple Ice did not prevent corrosion like WaterWetter did. For that reason, I'd stick with Redline WaterWetter as opposed to Royal Purple Ice.