Radiator Coolant, any better than others?

[ol' boy]

While i'm in the mood, think i'll flush and refill my Coolant System.

Anyone in the game recommend a Coolant these days?
Seems so many, Red, Green, etc etc

Just need to lower my boiling point and have enough for this Snow Season

Thanks

[ol' boy]

Nulon Green it is

[Bigfella237]

Did I miss a post in between or something?

You have to be wary that some coolants don't play well with others too, so just make sure you give the system a really good flush if changing types/brands. And remember to open the heater circuit beforehand too so as to flush that as well (doesn't hurt to give the heater core a reverse flush occasionally either).

[Tiny]

The colour is not necessarily important.
The best one is the type recommended by your engine manufacturer. It's all to do with the additives compatibility with your cooling system seals & engine metal make-up.
The major motor stores usually have a little book or chart to tell you what goes with which engine/car manufacturer.

Other than that a small amount of Ethylene Glycol can kill cats & dogs & Propylene glycol does not.

[gordon_s1942]

There is one coolant on the market that claims to meet all specifications and NEVER needs changing.
h

Sent from my GT-P5210 using Tapatalk

[Rick]

The most important question is, what type of car?

[bob_m_54]

The colour is not necessarily important.
The best one is the type recommended by your engine manufacturer. It's all to do with the additives compatibility with your cooling system seals & engine metal make-up.
The major motor stores usually have a little book or chart to tell you what goes with which engine/car manufacturer.

Other than that a small amount of Ethylene Glycol can kill cats & dogs & Propylene glycol does not.

Ditto... And sometimes even they get it wrong, like they did with my old 92 Forerunner. Apparently the head gaskets and coolant weren't compatible, which resulted in a huge recall. My, at the time, 10 year old Forerunner was recalled by Toyota and had the heads removed to inspect the gaskets and heads for corrosion, caused by galvanic reaction between the gasket metal material and heads. If there was too much corrosion, they said they would replace either just the heads, or heads and engine block. As it turned out, they said all that was required was a head skim and new gaskets. Unfortunately they wouldn't cover the radiator, which had a series of pin hole corrosion leaks in the top tank, right on the surface level of the coolant.

[ol' boy]

Thanks fellas

Its in an older Toyota 2RZ-E engine, 2.4i Petrol
I hadn't checked what the Manufacturer recommended.
The Nulon said is was "Guaranteed to suit every vehicle".


When using the Nulon Vehicle Selection Chart, i get either of these 2 Coolants





Currently there is NO Coolant in the system, it is just water, until i got a replacement Radiator Cap.
Vehicle runs around 10 degrees warmer with no Coolant is my estimation.
(or perhaps that is the radiator cap leaking slightly)


It has been a long time since i've flushed a Coolant System

Is there i recommended procedure?
Just dump it? Or run the engine with a hose feeding in fresh water? Or try and squirt a hose in the system reverse to normal flow direction?

[jamie_s]

go for the genuine toyota red coolant

[ol' boy]

go for the genuine toyota red coolant

I suppose there is an actual Toyota Coolant also
Found this, interesting:

Just to prove a pont, the local Toyota parts guy, Mal, put a nail in a bottle of green coolant, and another nail in a bottle of Toyota Red. Six months down the track, the nail in the green stuff was really corroded. However the nail in the Toyota Red, had not deteriorated.

One problem in an engine cooling system is the potential difference (Electrical) between the metals in the system. Some coolants will work as a more effective electrolyte than others. The Toyota coolant seems be be more neutral.

The other consideration, is to avoid mixing the 2 types of coolant. Without a pressure flush, the dregs of one coolant type mixing with another, can and will cause coolant systems to block.

Have a bit of a look at the old forums, there are some shocking pictures, provided by one of the forum users. The guy worked in/ ran a radiator shop in Qld.

Jesus!

[Rick]

go for the genuine toyota red coolant

+1 for genuine coolant, its all I use in my Toyota

[ol' boy]

Dam, i got 5 Litres of Nulon Green Concentrate for free.

I must admit, for the passed 15 years, no much interest or care has gone into what went into the Coolant System

[Tiny]

Currently there is NO Coolant in the system, it is just water, until i got a replacement Radiator Cap.
Vehicle runs around 10 degrees warmer with no Coolant is my estimation.

That's unlikely as water on it's own is the best heat transfer coolant, however it has no lubrication ability of cooling system components or anti corrosion, anti boil or anti freeze properties.

It has been a long time since i've flushed a Coolant System

Is there i recommended procedure?
Just dump it? Or run the engine with a hose feeding in fresh water? Or try and squirt a hose in the system reverse to normal flow direction?

This is going to be very subjective & opinionated in the responses you will get to this question.

My 2 cents, Recommended would be to flush top to bottom with demineralised water until no colour, then introduce the new coolant.

I wouldn't worry if I had to flush with tap water using the hose until clear, then introduce a 4 litre bottle of demineralised water, wait a few seconds, let the whole lot drain out. Plug every drain, Then refill will with the recommended coolant.

EDIT: FFS it's only got water in it now, just drain it and put the coolant in, in the correct ratio.

[jamie_s]

drop the current water out the radiator
refiill with water again run it for a day or so and drop that again
then put toyota red CONCENTRATE in it also as the block still has a couple litres of water in it dont use the premix

[Jazo116]

For a coolant change:

I usually pop both the block drain (if it has one) and the radiator plug. If I can get to the heater core lines, i pop those off and blow compressed air through to flush it out.

If you can't get to or there is no block drain, sometimes pulling out the waterpump is easy if its serpentine belt driven. that will drain a good portion of the block. On a Toyota, however, it probably timing belt driven pump (a bit more involved). Usually the Toyos have a block drain, though.

Top it off with premix, run it with the heater on at 3000 RPM or so until the heat starts blowing from the vents and you're usually in good shape after that.

Having a funnel like makes the bleeding of the air much easier and less messy.

The only cars I've ever had to "flush out" like with the hose, are cars that have some type of foreign substance in there, like rust in the coolant from lack of maintenance, or that "stopleak" junk that never works. Otherwise, I just empty and fill.

I try to stick to the same coolant the OEMs use - due to the varying factors of the silicates added. BMW and MB use blue, Porsche Pink, GM uses DEXCool, Jag has an Orange colored one, etc.

I add some to my own premix for better cooling performance in my vehicles.

Good Luck.

[ol' boy]

Interesting

[Tiny]

yes I've heard of the Evans stuff before, but never looked into it.
Interesting video. Thanks.

After watching that I looked at a couple more.
If you are going to use this stuff then, you need to follow the procedure in the the following videos.
Wonder how much the Evans Prep Fluid costs? Not cheap at all - see supercheapauto link below.





here's a couple links that may be helpful for those that want to use this stuff.

[ol' boy]

Yes, i remember the Thread here about Waterless Coolants
I didn't take too much notice at the time.

Jesus, i've learned a lot about Coolants in the passed 24hours!

I now realise how Old School i've been.
I've come from a different era

[lsemmens]

Isn't water a coolant? 'sall I ever use.

[Tiny]

Isn't water a coolant? 'sall I ever use.

yes absolutely; water is the best coolant you can get as it has the best heat transfer, however it is corrosive, it freezes & boils too easily, & does not lubricate the water pump seals, so early cooling system failures will occur without some sort of additive.

Personally I'll still stick with the engine manufacturers recommendations & change what coolant I have when it passes it's expiry date.
I think it still works out cheaper.

Now I did a bit more research on this Evans waterless coolant today & found that it is basically Propylene Glycol with additives at 100% concentrated mix, no water involved.

On the plus side; it is eco friendly, long life, no corrosion & excellent lubrication.
On the minus side it is expensive & it has a lower heat transfer than just water or Ethylene Glycol + ~50% water or Propylene glycol + ~50% water coolants.
The fact that it has a lower heat transfer means that if your vehicles cooling system has a fair margin on top for heat transfer it will run your engine at the correct temp, however if your cooling system is already at it's limits, your engine will run hotter without additional cooling system improvements.
Is this bad that your engine will run hotter? Not necessarily, however you need to know what your engine can handle at it's upper limits.

I found this interesting post on the subject & so I'll defer to this fellows better understanding.

Here is the theory with Evans (or any coolant for that matter)
First of all, discard everything you think you know about coolant temperatures. Coolant is the bucket in which heat gets carried away from the engine and dissipated in the radiator. The actual temperature of the coolant is only a factor in situations where the coolant boils. What happens with traditional EG and water is that it can boil at lower temperatures than straight coolant. People experience nucleate boiling at 230 degrees of indicated temperature, they blow a head gasket and get a warped head. From there on out, it is forever legend that and proof that 230 degrees can warp heads. This is far from the truth.
What happens is that the coolant mixture might be averaging 230 degrees at the sensor, but above the chambers it is beginning to boil. Everywhere its boiling, it doesn't have contact with water... which makes things hotter... which makes more boiling... which makes less contact. Then of course you have areas of extreme heat and areas that are still in contact with water. That is what causes the warping and head gasket failure.
The thought behind NPG is that when you remove the water, you remove the possibility of that nucleate boiling. At that point, the actual temperature of the coolant has very little to do with how effectively it transports heat. We're programmed to think that 220 degrees is too hot, but its only too hot because of the water in the coolant.
As long as heat out = heat in, the temperature will remain constant at or near thermostat temp.
One of the downfalls of NPG coolant is that it is not only less capable of carrying heat, it is slower to absorb and shed it. Its specific heat capacity is less than that of water, so depending on your vehicle, you may need increased airflow or a more efficient radiator to make sure that heat out is greater than heat in.
However, one of the points to NPG is that you can temporarily have greater heat in than heat out (increase in temperature) without much consequence. As long as your oil temps stay in check, (250 or less for conventional, 280-300 for synthetic), let the temperature rise. 300+ was a common thing to see in my Caddy 500 with Evans NPG on a long hill climb while towing.
Benefits: No pressure cap, so it has a greatly reduced chance of leaks or blown hoses. Increased lubricity for water pump. obvious benefits to rust reduction in the iron castings. No boiling. Hotter engines also tend to be healthier. Its so programmed into us to keep engines cool. We run cooler stats. The thing is, engines like to be hot (within reason of course). Without nucleate boiling, there are is less chance of detonation. That might be a nice benefit in a boosted application. When your car overheats and starts detonating, its not because 230 degrees is too hot. Those flame fronts are seeing 2000 degrees F. 10 more degrees of coolant temp isn't what is causing the detonation, its because the chambers have boiling coolant on the jacket. Its not the temperature of the chamber or the coolant, its because the timing advance is tuned assuming that the chambers and coolant are adequately moving heat away from combustion. When you get boiling, it can't pull that energy away and you get detonation. Put it this way... if you get detonation at 230 degrees with 50/50, that does not mean you'll get detonation with NPG at 230 degrees. The point is, without water to boil, Evans maintains constant contact and heat transfer regardless of its temperature
Drawbacks: When not running a pressure cap, you can experience a constant sweet smell of coolant. Without water, there is reduced heat capacity in the coolant so it may require increased efficiency elsewhere. Its expensive stuff.
It does have the nice benefit of not requiring an anti-cavitation additive in diesel applications. Diesel engines also tend to be much more thermally stable - larger capacity for coolant and oil, larger radiators, much more cast iron, etc. That is one of the reasons why its targeted at fleet applications. As you can imagine, a 3000-lb Detroit engine assembly that holds 19 gallons of coolant means that temperature rises would be gradual, but imagine a 1.5L aluminum 4-banger with a coolant capacity of 2 gallons. Temperature changes can be much more abrupt in the smaller engine.
As long as you understand that heat and temperature are linked but not equal, it makes sense. I liked Evans in my Caddy 500, but it wasn't really a big benefit. I can imagine it would be great in larger applications, but not a benefit in smaller applications.
You originally said, "So on one hand, it's got a much higher boiling point so there will be less chance of hot spots. But on the other, it apparently has 30% worse heat transfer than water, so while I may not be boiling it, it may not be cooling enough either..."
As long as its not boiling, and as long as it is not increasing temperature, it is cooling adequately. It doesn't really matter if its 180 degrees or 280. As long as you keep oil temps in check, it should be fine.