My YRV Turbo hit 100 degrees C today


Well I know it was a hot day today, but on the way home from work I noticed the water temp gauge on my Scangauge was in the low 90s but once on the get go the temps could rise to 100 degrees c. I can only put this down to the Evans waterless coolant as this is the first time my temps have hit this magic figure. Plus I have a race radiator on the car.
The only thing that doesn't help is that the water and radiator is also cooling not just the engine but also the turbo and auto box. What was weird is that turbo still wanted to over boost and give max power, so can only put this down to the Evans and the fact it doesn't boil at the high temps Smile

probably wont boil till about

probably wont boil till about 115c anyway as its a pressurised system and not of water content.

Full of ideas but no time to do them!!
youtube: Redfourtrack

Evans Waterless Coolant

I see Evans waterless Coolant has popped up as a topic again and I got thinking about this stuff once more. It interests me a lot but only from an academic and curiosity point of view. I know some on this forum do use it and I don’t wish upset anyone – if it works for you, go for it. Personally I am staying away from it.

The www is full of praise for the product and it is very difficult to find any views against it, which makes me worry I am really out of step with the whole world. I gotta say I just don’t understand this product and maybe I am missing something. By all means please tell me.

Firstly plain old water is the best fluid for transferring heat and it transfers heat more effectively than any other fluid, which is why it is used as a coolant, and indeed as a baseline to measure other fluids heat transfer properties. The problem with water though is that it freezes, and causes corrosion and subsequently it is always used in conjunction with additives, ethylene glycol and anti-corrosion chemicals, but the biggest proportion remains water because it is the best heat transfer fluid. The glycol and anti-corrosion additives are basically modifying the perfect coolant to suit real world use.

From what I read Evans is 100% glycol of some sorts, and glycol is only 2/3rds efficient as water at taking heat away, so my basic thought is if it does not transfer heat away as efficiently as water why is it rated so highly as a coolant. Evans, for me, falls down on its most fundamental purpose, which is transferring heat away. And this is the thrust of my basic doubts about it.

I understand Evans has a higher boiling point than water and it would need to have, because it is holding on to more of the heat, and that in turn will raise engine temperature, which can’t be good for an engine designed to run within a certain parameter. Off the top of my head I can think of many bad things happening from raised engine temperatures.

The electric fan will probably be running permanently because the ECU is designed to switch it on at a temperature based on a water/glycol cooling system and not one that is holding on to the heat more and raising temperatures. Cylinder head temperatures are going to climb and this can cause all manner of issues, many of them terminal. The engine oil is going to get hotter as well and be under more stress. There is too much detail to set down on this overheat issue, and none of it is good, so I will leave it at that.

Furthermore Evans being 100% glycol of some sorts it is subsequently thicker than water and this raised viscosity has to have a negative effect. For one the water pump is working harder to shift the same equivalent volume so the engine must be working harder with more heat being generated. It is interesting Evans sells high flow water pumps for some vehicles. There are more issues on this theme, but you get my drift.

The other downside for me is the cooling system has to be all but completely dry (97% is required but preferably 100%) of water before priming with Evans and if it isn’t it loses any supposed benefits. I defy anyone to completely dry out a coolant system without a complete tear down and blowing it with a hair drier for a week. For me this is way too much hard work.

I would like to hear some thoughts on this topic because I am darned if it makes sense to me to swap ordinary engine coolant for something that to my mind is unsuitable.

What do you reckon?



Can of worms !!

Your sure opening a can of worms here Phil.

I use Evans in my Rally 4 engine.
I use it because it is more thermally efficient, it picks up the heat more efficiently from the engine and then loses it more efficiently at the radiator.
My radiator fan is NOT continually running.
It does not boil like water so there is no vapour / steam around the cylinder head so there are no hotspots. There is very little pressure in the whole system (Around 0.7 psi)
A normal system is more like 13 psi or more which puts far more strain on all the components it is trying to cool and eventually will blow the head and Water Pump Seal.

No water - No rust..

You never have to change it.
You can drain it - Run it through a sieve if you want and put it straight back in.
It is slightly thicker, but I defy you to be able to see the difference, I have seen or felt no detriment to my car at all and I have been running it for 2 years now. I have blasted my car around Cadwell Park on Track Days and it ran perfectly and the gauge never moved. It runs around 92c all day every day no matter the weather.
It now has 95,000 miles on it and 30,000 of them have been with the Evans in it.
When I changed to Evans you use another chemical water soak up first to get all the water out. When mine was tested it still had 1% water in it. When the car is hot you take off the cap and whats left of the water evaporates out. You do this for a couple off weeks and then the next test was completely 100% Evans.

You can take the cap of as well when very hot as I have done (Carefully of course) and it just give s a little puff like noise and puts a bit of the Evans in the Overflow tank. Try to take the top off a water system when hot - Er No dont !! You know what will happen and you live too far away for me to visit you in hospital and say "I told you so"

I love the stuff - and when my second engine which I am trying to sort out parts for now is ready I will be putting Evans into it. - Without Question. Smile

Racing Drivers use this stuff because they can use smaller Radiators in tighter spaces and still get good cooling and lighter cars. So in a standard car the cooling is even better and many vintage car people use it because of the pressure advantage. Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.

Oh gawd!


I thought long and hard about posting on this subject so firstly, I am not looking for argument, and I know you aren’t. I am just putting it out there that I have doubts. Like I said I feel as if I am the only one that thinks this way.

You are correct that many people use it in many applications and they swear by it. My thoughts are based on what I know about the laws of physics and I keep coming up with the same answer.

Now, I will disagree with you about it being more thermally efficient than water based systems – picking up heat and then losing it at the radiator. I believe the product information is sort of correct, but crucially only when a system becomes so over-heated a water based one would boil off to vapour, and the Evans would continue to function because it boils higher. And that is how Evans gets away with that statement of thermal efficiency – it is a bit ingenuous.

So the product information is a bit weasel – it lets it be believed it is more efficient at transferring heat, and it is not. It is only more efficient beyond the boiling point of a water based coolant, it is not a better fluid transfer medium than water.

Evans absolutely does allow an engine to run hotter without boiling off the coolant. So under normal use for a normal car engine system I see no real benefit and I still believe there is a downside by actually causing over-heating as I stated in my earlier post. When used in a system designed to function at temperatures beyond a water coolant system I agree Evans is the way to go.

It is an extreme coolant for extreme conditions and systems, which most of us will never see.

Oh gawd, what have I done?


Nothing !!

Youve done nothing except what other people have done. Which is to question a product that you have never used.
I did exactly the same. Smile
I talked to the company for a long time and decided to give it a try.
I do not regret it.

I do not get paid by them and I have no shares in their company. I just use it.

Also dont forget - No anti freeze required either, down to -40C.

Why do Vintage Car owners use it Unknw If anything their Cooling Systems were not very good at all. So they use Evans for better protection. Be it cooling or little pressure and no rust and scale.

Maybe we should ask them.

I use it.
It is a personal Choice.
I am not looking at a bit of paper or using the laws of Physics or anything else.
I have never had to top it up or change any Pipework that is leaking after 13 years of hard use at the high pressures that a Water system has !
(Except for the last two years of course, because there is little pressure with Evans)
Many on here have had and still have doubts - People have called it snake oil and all kinds of things. So why are other people around the world using it -
Its not cheap.
It works. Thats it. Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.

This has been Used on Wheeler Dealers


Just to add to your comments. I too was sceptical about this product since you harked on about it a couple of years ago Smile
But owning something like a YRV Turbo where the engine, turbo and autobox is being hit hard and therefore requires very frequent service intervals which = Costs a plenty over a normally apsirated car Sad
So from my point of view I chose to use the product to see how it would help my situation as the YRV turbo radiator and water/coolant supply is doing more than cooling the engine, but also the Turbo and the AutoBox (People do forget this on this model). Also to help save on the cost of replacing the coolant every so many years. I also use this product in my other car (Subaru Impreza STI) which again there has been no issues.
Just to add that the last season? of Wheeler Dealers (Shown on Sky/Virgin TV (Discovery Channel)), the mechanic on the show (Edd China) actual used this product in one of the cars they were doing up. So there must be some merit if an accomplished mechanic with years of experience had no hesitation about using this product. As many will say it's down to personal experience, and at the moment I have been using Evans in both my cars for close to a year now. The only downside is if you have a radiator leak and you need to refil, then thats where it gets tricky if you dont have any spare Sad So not all good Smile

'12' Plate Mazda MX-5 2.0 litre NC 3.5 Venture Roadster 160BHP
'15' Plate SEAT LEON 184 FR TDI. 240BHP/500nm Torque.
Past: '53' Plate Yellow YRV Turbo Approx. 150BHP

I am still not convinced.


It was your original post here that got me putting pen to paper because it appeared to support what I have always thought about Evans Waterless Coolants.

You say ‘I know it was a hot day today, but on the way home from work I noticed the water temp gauge on my Scangauge was in the low 90s but once on the get go the temps could rise to 100 degrees C’. From that statement I take it that you are expressing some surprise at having those temperatures and it is a good thing to be running near a 100 deg C.

You then state ‘I can only put this down to the Evans waterless coolant as this is the first time my temps have hit this magic figure’. From that it appears these temperatures have never been this high until changing to Evans, and once again you seem pleased your motor is getting up near the high end of hot.

Once again I am not looking for an argument or trying to be picky. Statements have been made and I am looking for some proper facts that support the use of Evans. I stand by what I have written because the laws of physics can’t be denied.


You say that your motor runs at 92 deg C. Now I reckon that is on the high end for that engine because the fan is set to come on at 96 deg C and go off at 94.5 deg C. So you are within limits but up near the top end, which doesn’t sound correct for how a designer would have it. The thermostat opens at 80 deg C so something isn’t right if you are making 92 deg C as normal.

I am sure you both love the stuff and that is fine by me, but I just don’t see why it is lauded so much. Neither of you has made a compelling case for its use and indeed you have made cases for actually not using it – both of you report high coolant temperatures. The statements from both of you supports what I have been saying about Evans – it makes engines actually run hotter. In which case it plainly is not a very good coolant.

Correct me if I am wrong. Sorry guys I am not won over. What am I missing?



Fair Comment

I do appear to be pleased about the hot temps as it's how I have written it, but in reality it has got me worried in some way. In the past whilst using the standard water/coolant mixture and doing smaller journeys to work, the temps would hit around 94 degrees etc.. on a warm/hot day but now I am doing higher mileage on both a mixture of Motorway and Dual carriageway it makes me think that I maybe having higher temperatures than normal. With the Scangauge this gives me an accurate picture of actual temps rather than trusting the standard needle gauge, which pretty much only tells you when the engine water temp has normalised. I can only put the higher temps down to the way I also drive my car as well (As mentioned the YRV TUrbo cooling system is deigned to provide cooling to the engine, Gearbox and the turbo), so doing a hell of a lot for a 1.3 engine which is being driven hard. But I have the comfort of knowing at the moment, that A).. this stuff doesn't boil and B).. It's the life of the engine.

'12' Plate Mazda MX-5 2.0 litre NC 3.5 Venture Roadster 160BHP
'15' Plate SEAT LEON 184 FR TDI. 240BHP/500nm Torque.
Past: '53' Plate Yellow YRV Turbo Approx. 150BHP

Its interesting !

I use it for its protection properties such as no rust or scale. and no pressure in the engine. The lack of pressure and no hots spots in the cylinders is the main thing in many ways. These two things cause more engine damage than anything else put together.
My Thermostat opens at 80, so it then goes to the radiator and Heater matrix of course to warm us up on a cold day. My car warms up more quickly with the evans and thank goodness it did this winter. I know what the physics says but it definitely warms up more quickly than when I had water in it. I have had a proper temp gauge fitted for some time now. My car ran around 92/96 with water in it. Sometimes my car got up into the 100s when given a bit of hammer.
It has never done so with the Evans. I hardly ever hear the radiator fan go off although I do hear it when the A/C is on. It does not surprise me that the Turbo gets much hotter then mine as there is much more cooling to do.
I suppose its all a question of perpective in the end and what you beleive you want and what you beleive you are protecting in your engine.
I am no expert in Physics at all. I can only tell you that my car runs better with the Evans than when it had water in it. I do not have to convince myself or anyone else for that matter. I researched it I liked the ideas it put out. I talked to them I tried it - I think it is extremely good and will continue using it- Only time will tell. We all have out points of view. You have mine. You have Jons, and we have yours Phil. Thats it. Smile

One day maybe we will find out one way or the other - Who Knows. Enough for now. Iv'e gone through this all before. I am not here to convince anyone. These are my thought - And we have Phils thoughts and Jons. Lets leave it at that. Cos we certainly aint going to agree are we. LOL.

PS Yes Jon sorry. I actually saw the Wheeler Dealer show you talked about (In fact I watch it avidly as I find some of the stuff they do on there useful to know)

He did indeed use Evans in a Car because it had a poor Cooling system and he wanted less pressure on the Cylinder head as they were prone to warping. It will be on again one day. I will have to take note of the car it was on - I cant bloody remember. My age of course. LOL.

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.



Reading the detail of what is here you have both implied your engines run hotter with Evans, which is what I assumed Evans would do to an engine and was the original thrust of my initial post.

I have, since we started, found other car forums on the www that have their members stating that running hotter is a usual consequence of using Evans. So I now find I am not alone in my thinking.

I am not attacking anyone here and I have gotten the confirmation of my supposition. Thankyou for the input.



Interesting again !!

My car definitey does NOT run hotter.
Make of it what you will.
But it certainly doesn't Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.

Phil, You are not daft at


You are not daft at all. High glycol content waterless coolants are snake oil.

They serve no improved function, they have a lower specific heat capacity than a typical mix of oats/dexcool/hoats antifreeze.

After running a snake oil product similar to Evans in a high performance application, it was changed back to a typical antifreeze which saw better on load radiator coolant return temperatures, and cylinder head temperatures.

From my testing the snake oil did a far worse job of carrying heat away from the cylinder head and to the radiator for displacement.

It does resist boiling better though, which is a problem I have when high performance turbo cars are brought to tick over straight after prolonged high boost. An auxiliary water pump could resolve this though.

Just because some mechanic guy on wheeler dealers uses it won't sway me, they get alot of products given to them for product placement anyway. Alot of what i've seen on that program has to be taken with salt.

For Hijet manuals and information

Interesting !!

I used Evans coolant long before it was ever on wheeler dealers - I have been using it for the last 4 years now. I have NEVER had to top it up. My engine cools just as well as when it had water in it. My engine isn't rusting inside. My engine has no pressure in the water system so no burst pipes or leaks or pressure on the seals of the water pump or head gasket.My engine is lubed by the evans. My engine has no hot spots and no cavitation. My Fan is not continously on (Sorry if I spelt that wrong - before someone has a go at me)
My engine runs as sweet as a nut is quiet with no rattles inside or out.
That's my personal experience from running Evans over the last 4 years.
I will continue to use it and will also put it in any other vehicle I own.

You pays your money and you takes your choice. I choose to use Evans coolant. It is the best product I have ever used. Smile

You say you used a product "Similar" to Evans ??? Clearly it wasn't Evans. Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.

"My engine has no pressure in

"My engine has no pressure in the water system so no burst pipes or leaks or pressure on the seals of the water pump or head gasket."

Then there is something wrong with your coolant system.

Unless its a canal boat, every coolant system ends up pressurised due to the thermal expansion coefficient of the fluid. Radiator caps are pressure rated for a reason. If you are not pressurising then I suggest you do some pressure testing and inspect your rad cap.

On the website I love how they say:-

"Q. Will Evans Waterless Coolant cause my engine to run at a higher temperature?
A. No. The operating temperature of the coolant may increase slightly, however the temperature inside the engine will be more consistent."

Well a dashboard temperature gauge reads the coolant temperature. How can anybody measure "the temperature inside the engine" - where exactly?! The coolant should always stay the same temperature while there is air coming though the radiator, as that is what your thermostat is there for.

Their whole product literature skates round all the important details of a thermal transfer fluid - e.g. Specific heat capacity.

But if you email them, they will tell you that their Non-aquous Propylene Glycol coolant is made from:-

Ethylene Glycol 66–70 %wt
Propylene Glycol %wt not specified
Water %wt not specified but from Evans webpage info it should be <3 %wt
Proprietary Corrosion Inhibitor Package <2 %wt

And they will tell you:-
Evans Coolant specific heat capacity of 0.66 btu/lb/f

So would you not be better off using either:-
Pure Ethylene Glycol specific heat capacity of 0.71 btu/lb/f

or that over rated boring old common fluid:-
Water specific heat capacity 0.998 to 1.005 btu/lb/f

Basically, they are selling you 100% antifreeze.

For Hijet manuals and information

Wow! Holy Thread Resurection Batman!

Didn't think I'd see this post come back from the dead Wink
Just for the record, my YRV Turbo still has the Evans and I even had my last Subaru Impreza STi's radiator water replaced with it. Must say I noticed no fluctuation in higher temperature with the Subaru when I had it.
I can only conclude that smaller engine cars with smaller radiators and that the water is also not just cooling the engine here but also the Turbo and the Auto box on the YRV Turbo must be the cause for my overheating issue.
Interesting to read that someone else is having a go at this product. The only reason I am using it was to cut costs at not having to have the radiator drained and refilled every 3 years. So will be interesting to see what other comments are on this subject again Smile

'12' Plate Mazda MX-5 2.0 litre NC 3.5 Venture Roadster 160BHP
'15' Plate SEAT LEON 184 FR TDI. 240BHP/500nm Torque.
Past: '53' Plate Yellow YRV Turbo Approx. 150BHP

The very highly strung wide

The very highly strung wide body Subaru STi I had in the workshop would go into an overheating spiral with a waterless coolant fluid while being driven continuously on boost, until it would end up with the needle nearing the max.

This vehicle is running around 28 psi of boost on forged low compression internals, with a custom radiator and intercooler, along with aftermarket management etc. As you can imagine it packs a serious punch, almost fearful to drive on a public highway. As such its tests its coolant system to the max.

After much research on coolant mixtures, and their specific heat capacity I opted to change it to a very low glycol content mixture, and now it now it keeps a temperature equilibrium when driven on continuous boost.

Although Bob will disagree, even waterless coolant expands as its heated, that is physics/chemistry in action. The coolant pipe work should be quite firm to squeeze when at operating temperature, approximately 0.5 to 0.8 bar above atmosphere at around 80 degrees. If his system is not ending up pressurised at its operating system then I would suggest it does need close inspection, if it isn't loosing any coolant then I would look at the radiator cap as this is the pressure control device. I use alot of radiator caps as I repair lots of hijets which have 2 radiator caps, and many on the copy parts market simply do not work - they love me at the motor factors!

I am not a chemist, so I will keep my possibly flawed maths to myself with my assumptions on exact ratio of Ethylene Glycol (stated 66%) which expands greater than water and Propylene Glycol, but from my calculations when working on the Subaru, the waterless coolant expands at almost exactly the same rate from 20 degrees to 95 degrees as water.

The only advantages to waterless are it does not boil as early, and it has better anti corrosion properties.

I am not here to change your ways, but only to voice my opinion! Wink

Likewise if someone could offer me engineering evidence of the improved coolant capability of a waterless coolant then I am all ears. I think it is strange the Evans themselves do not publish the factual specifications of their magical super heat transfer fluid.

For Hijet manuals and information


I did not say it does not pressurise at all. I said it just does a gentle puff when you take the top off. It doesn't pressurise enough to over expand into the tank.
Because there is no steam at all the coolant gets into every nook and cranny as a liquid and cools the spots that steam obviously cant.

That's all I'm saying. No more no less.

And for the last time. My car has run as sweet as a nut on this stuff for nearly 4 years without the slightest problem.

I cant really say any more can I ?? Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.

Pressure !!

There is no pressure because the product does not boil. It is the boiling of water that produces the pressure as steam. No water no steam. Yes it gets hot, it does not pressurise, it goes around the system very nicely thank you and keeps my engine running nicely and it does not over heat in any shape or form.

If I take the cap off when the engine is hot there is no explosion of water and steam. It occasionally just very gently "Puffs" a little. (Sorry - that's the best way to describe it) So there must be a tiny bit of expansion but not enough to make the Radiator cap release anything !.
I am stating facts here from 4 years of use in my high compression Sirion Rally 4.

And this car has been taken around Cadwell park race circuit ! Some of the lads there were very skeptical there as well.
They were not by the end of the day !

You can say and discuss all you like - but until you have properly used it Unknw

Oh the 3% water you mention. That is what they would like your engine to be at or less, when you drain out your water antifreeze mix before putting in the Evans.
They also suggest that for the first few weeks you take the Radiator Cap off after getting the Evans Hot - This is so any water that may be left in the engine can naturally leach out to atmosphere as steam.

That is what I have found. After 4 years of using Evans, I should have just a little knowledge of the product and its effects - Wouldn't you agree UnknwSmile

Oh and by the way. I am not getting paid by anyone or by Evans Coolants for saying any of this. I would say it to anyone for free.
I use Evans -
Personally I think it is Superb. Smile

2003 Sirion Rally 4. And I love it.
Don't like the new shape Sirion much.Sorry.