I may be crazy but seems I also read that reverse flow systems work best with this stuff. Seems at $15 a gallon for 50/50 and most cars very happy with it there is no reason spend that kind of money. Steve (CTR)

It appears so based on my skimming the book chapter on Evans coolant. It says "... the Evans coolant system was based on a non-pressurized cooling system." Also from a description of an Evans-designed radiator for its system - "The filler cap is a screw-on, zero pressure cap, with the vent built into the neck."

One more: "Because the Evans NPG coolant works well as either a non-pressure coolant or a low-pressure coolant, it is ideal for antique and classic cars, as well as modern applications." I can see it being a clear win for old cars without pressurized cooling.

On the topic of expansion space, it doesn't say explicitly but it sounds like, while not necessary, it could be desirable. On a low/no pressure system, flow rate is all important. If pressure builds up in the radiator, it would mean impeded flow, so having somewhere to contain expansion and help maintain flow would be desirable. But it wouldn't seem to be actually necessary if the system won't get close to its pressure limit.

Further text describes how a cooling system should be designed for the Evans coolant, and this may be another reason OEM's don't use it - you really would design the system differently than a water based one, and so to use this stuff to proper advantage they'd be committing to it exclusively (assuming all claims are true.) Consumers probably wouldn't react well to such a choice, whether it was superior or not.

Still, a race team could commit to it. I'm not sure how many race teams use it, or if it's already standard for racing coolant designs (it's not very well publicized to me, if this is the case.)

well, everything that is heated expands, but as pointed out, this fluid will be far from its vapor point so the amount of expansion will be far less than it would have been with water in there, not sure if the difference would be enough to take advantage of, or just a curiosity

Good question. The primary reason (as far as I know) for a pressurized system is to raise the boiling point.
Another question: If it doesn't need a pressurized system would it still need expansion space in the rad, or alternatively and overflow catch system?

(I think I need to go lube my poly bushings )

Am I correct in thinking this stuff is used without a pressure cap? I have removed a charge from a race car and saved it maybe 10 years ago. I have never been tempted to try it. My 1360 Cooper S likes to run at 190/210 all the time blanking plate no thermostat. Super two core, tropical fan,  large pulley, 15 lb cap and MGB recovery tank. Steve (CTR) 

I actually do have a bit of information on the Evans coolant from a book called "Automotive Cooling System Basics" by Randy Rundle. It has a chapter on the product, and is enthusiastic about it. As far as I can tell he's not an Evans shill. That's where a GM report on the stuff is printed.

I didn't see a figure for thermal coefficient, but it did state that studies indicated, in theory, the flow rate of the coolant through a given system should be increased by 27% to compensate for the lower transfer properties of Evans NPG.

However, this is in theory. In practice, it says that lower tendencies to form vapor bubbles (by the Evans NPG), partly due to lower surface tension (think about "water wetter" products) and much higher vapor pressure compensate for its lower heat transfer properties.

Other points of interest is that Evans is meant to run at higher boiling temps - so it is not the intent to lower coolant temperatures. You want it to run at higher temperatures, because of its much higher boiling point. When running at these higher temperatures it is capable of transferring more heat, just as anti-freeze helps a water cooling medium carry more heat even though pure water transfers heat better (because anti-freeze raises the boiling point.)

If you can increase coolant flow, then the gains could be even higher.

So there appears (to my layman's eye) to be sound principles behind it, probably more so than polyurethane suspension bushings. But I still think (for me) that it's not worth the trouble and expense to convert, and I have to think OEM's feel the same way. But others may find the benefits worth it. Decide for yourself!

That's good to know. Restores my faith in OEM engineers. Your other points, especially your personal experience with waterless coolant has convinced me. Thanks.

To answer a couple of questions raised:  All manufacturers use distilled water when filling their cooling systems with coolant (only a fool, or a very inexperienced person would use anything but distilled water for the very good reasons already mentioned).

The problem with corrosion and cavitation with normal water based coolant isn't caused by impurities in tap water, it is caused by the nature of water used very near its boiling point and the difficulty with preventing cast iron from corroding.

Getting back to the original question:  I've now used Evans in a motor for two years (fresh rebuild with all new hoses, parts and newly rebuilt radiator and heater matrixes).  No problems found.  Also, no corrosion where there always was some before (at the base of the heater spigot, and inside of the thermostat housing).  Engine runs fine.  Temperature is fine.  

Probably OEMs don't use it because they don't build cast iron and copper engines/cooling systems any more!  They use all aluminum and the modern long life coolant chemistry takes care of them just fine.  Also, we all have to admit that water is the highest specific heat fluid out there, so it is more efficient to use (the cooling system can be made slightly smaller, saving slightly on mass to help meet modern MPG and emissions targets).

The benefit of a waterless coolant is in old, cast iron engines with only a few aluminum parts (water pump, etc.), where the normally best coolant is the old fashioned green stuff with the cast iron protecting phosphates which naturally are consumed over about 24 months and require flushing and refilling every 2 years, and still allows some corrosion to occur (stuck thermostat housings, corroded thermostat retaining studs, heater spigot bases, water pump inlet).

I'm sold on it because of those things.  The $40 is nothing when considering all of the rest of the cost involved with a rebuild, and being able to simply remove the thermostat housing after another 20 years is (to anyone who's struggled with that before) going to be priceless.

 
Norm

All good points. And I hadn't considered the polyurethane thing. Interesting. On the other hand, OEM's don't use distilled water in their cooling systems either—as far as I know. Go figure.

I'm always surprised that distilled water is seldom mentioned in these discussions. Not only does tap water contain dissolved minerals that are harmful to our cooling systems, it is highly conductive, which of course promotes electrolysis. Distilled water does not conduct electricity. The galvanic action between tap water and an aluminum radiator, iron block, various brass, copper and steel parts plus lead solder, not to mention the fact that our engine block is used as an anode in our car's electrical system make our cooling system a poster boy for electrolysis, so why would we ever put tap water into our radiators? 

The Evan's product sounds promising; I like it's anti-cavitation properties but I would also like to see the specs on it's thermal coefficient. Currently I'm running distilled water, 1 qt. of antifreeze (for lubrication) and 16 oz. of Water-Wetter for anti-corrosion and reduced surface tension. I've never stuck a garden hose in a radiator of any car I've owned.

The question I have with this stuff (like many "revolutionary" innovations) is this - why don't any OEM's use this stuff?

Some have studied it (like GM) but no one, not even Ferrari or McLaren, use it in their cars. If it is so superior, why not?

I think this may be a case like that of polyurethane suspension bushings, many thinking this is a vastly superior material - it is not. OEM's don't use it except in very specific and relatively rare circumstances for good reason.

OEM's (like McLaren and Ferrari) use either rubber or metal joints, not polyurethane. Polyurethane is a staple of the aftermarket because it is easier to manufacture in small quantities since you can make molds and pour the compound at room temperature, unlike rubber that requires expensive machinery. (Just a parallel to illustrate my thinking on this.)

It may be the advantages of Evans are outweighed by the disadvantages to the OEM's, and cost certainly isn't a factor when it comes to McLaren, Ferrari, top-end Porsches, etc.

Been using it in the mini for two years. The hard part is the prep. Flushing it at least twice with the prep fluid to try to get rid of as much water as possible. I think I still have more water than recommended as the system still has some pressure when hot. So I have had no problems with it and will continue to use it.

TTT

Its been awhile since this topic was created by Geo. 

Anyone had good or bad luck with this stuff?

I understand the concern for someone who is racing or running a 'hot' or unusual config.  BUT for the average user, having a way to protect from a temporary condition that might cause an overheat of conventional coolant seems worth considering.  Further the ability to not have to keep track of the coolant age sounds like a good thing. 
As mentioned, the majority of Mini owners aren't faced with severely limited finances or else we wouldn't own a car that is rust prone, cantankerous and just apt to break a key part at the wrong moment.

Has anyone used Evan's coolant for at least a year or more yet?  Reports back ?  I'm dragging my feet (due to an extended Honey Do list) replacing my radiator and now I'm giving some thought to the lightweight heater unit replacement as a way to avoid any future cooling system failures and get a more efficient heater.  (I like driving in cold weather but would rather not have a) Single speed Fan b) freeze for 15 minutes until real heat starts to flow)

 

If I am going to do a complete flush and replacement of just about all cooling system parts.... maybe switching to the Evans product now makes sense.  

Norm,

I agree with you on all points except one: I haven't been able to find any information on the thermal coefficient of this product. There is a brief mention in the video that it's not as efficient as water but there is no mention of how much lower it is. That is my only concern in a Mini.

For a relatively mild setup, I'm sure it would be fine. But for people who are pushing the envelop in terms of power (or plan to do so), it would be something to think about. It's not easy to significantly increase the size of the radiator to compensate for a less thermally efficient coolant.

Jean

Waterless coolant. When I first heard of it I was very skeptical.

Modern things are sometimes not well enough developed, even if they are a great idea. GM had a big class action suit against it because of failures in the chemistry of its first use of "long life" coolant, making it not long life if everything isn't just right. Later, the formulas were improved and that problem went away, but this is the sort of reason why I don't like to be an early adopter, to let the real world catch up with the great new ideas until they become a bit more foolproof.

Another reason why I was cautious, is because the modern "long life" coolants designed for use in aluminum systems are not chemically designed for protecting our iron/copper based systems.

But the more I look in to this waterless stuff, the more I am coming around. Here's the thing: the two problems above were both problems that had to do with the chemistry that was designed to deal with the shortcomings of using water as a coolant (water being a catalyst for galvanic reaction and corrosion means that it needs a bunch of clever chemistry applied to prevent those things). Waterless coolant eliminates that factor. So, if the new stuff has the proper thermal coefficient (the whole point of coolant is to transfer heat from its source to the radiator, this is why you don't cool with 100% ethelyne glycol, because it is not as good as water in transferring heat), and as long as the stuff has the needed working temperature range (the other reason why you don't use 100% ethelyne glycol, because it turns into sludge when cold and boils at too low a temperature, until water has been mixed with it). Then, you can eliminate the water (and its related corrosion issues that water brings with it). The third important thing with coolant is its ability to prevent cavitation (microscopic areas inside the engine where the coolant boils, becomes vapor and fails to transfer heat as well as it would have as a liquid, leading to erosion in the cast iron and hot spots/overheating). According to the literature, this waterless material has a higher resistance to it than water/ethelyne glycol mix does.

For a classic car, who cares what the coolant costs, if it will prevent all of the other issues that will occur over time whether your car is driven daily or sits in a museum for the next 10 years (erosion of the water pump housing where the hose connects to it, crud build up in the thermostat, fusing of the thermostat housing to the head so that you can't hardly get it off without cutting it off, corrosion of the thermostat housing studs, crudding up of the radiator and heater cores). All of that happens whether you change the coolant religiously every 24 months or not, because of the water in it.

I am now thinking that $40 is a bargain, if it does all of those good things, better than water and prevents all of those other negative things because it doesn't have any water.

From what I have read about the stuff, it seems to do all of those things.

The next time I am going to use this stuff and see!

Norm

On a Mini with good cooling capacity one can still get boil over after shutting off the engine.  Apparently the waterless coolant doesn't do this.  I would rather not have to add a catch tank in an already crowded engine bay, and some folks (like me) are trying to keep the aftermarket stuff off their cars.

 

But the product sure costs a lot.

But you don't use ethylene glycol without adding the same amount of water to it. At least it's not recommended by anyone.

Ethelyne glycol is not water either.

First let me say that I have no experience with this product. And there has been some discussions about this product not that long ago.

However, while having a coolant that won't boil over might seem interesting you also have to think about the reason why you would have this boiling over problem. If the reason you have this problem is that you don't have enough cooling capacity, do you think that using a coolant with less heat capacity than water or regular coolant will help the situation? It might not boil over but it won't run cooler. Would you feel comfortable running your engine at 250 degrees?

I'm not saying that this is what will happen but it is certainly something to think about. And you'll also notice they don't give the information about the heat capacity of their product anywhere on their web site.