Lets solve the TD5 coolant riddles for good.

[dobbo]

Just out of interest has anyone ever tried mixing coolants in a testube or another type of vessel and heating it too the engine running temperature? I have heard that apparently a gel or sludge forms in the radiator and blocks it thus cooks the engine, another story is through a chemical reaction an acidic is formed that eats the cooling system slowly.

With all these stories circulating about mixing cheap readily available coolants with OAT (red) for the TD5. I think it may be worthwhile for someone to do a bit of mythbusting and report back.


What other stories have you heard in regards to coolants in TD5's, please post so they can be tested as well.

So now the question


Does anyone have access to a lab or have a few basic pieces of lab equipment to test these theories.


Things needed

Beakers or test tubes
Bunson burner
thermometers
litmus paper
coolants in OAT (red) and any other colour, cheap coolant.
part of a radiator core (small enough to fit into beaker)
pieces of hose (small enough to fit into beaker)

[ddkemp]

Afyer many enquiries over the past week, ith L/R specialist from Brisbane to Sunshine Coast and Direct to Land Rover, They have indoicated the following

1/ Completely flush the cooling system
2/Use a Preferred Land Rover brand or select alternative
3/ Colour means nothing
4/Refill using either tank water or demineralized water
5/Dont use tap water, particularly with the dams low and the minerals in the water
6/once filled , bleed the system
7/ top and drive normally.
8/ DONT MIX COOLANTS OF ANY TYPE

I have decided to use Valvoline GO5 which I hhave sourced from MR Automotive, which is recommended by Land Rover and other specialists.
Thats my slant on it all
I hope that is of help
David Kemp
S11 TD5 Disco
S1 V8 Disco SE
S111 SWB

[dmdigital]

Mixing coolants can lead to reactions and changes in pH of the solution. Also when its time to change the coolant it has lost some of its properties and so is best flushed right out and replaced.

That said, like anything there is a dilution point that the coolant left is of negligible quantity when mixed with the new stuff.

Have a look at my findings on this thread: O.A.T. Coolant Replacement for Td5 (http://www.aulro.com/afvb/showthread.php't=35098)

Rather surprising what you find out!

[dmdigital]

Also looking at the make up of the Valvoline G-05 from the MSDS it is not the same as recommended by LR. Also the G-05 on the Australian Valvoline site does not appear to be an OAT coolant whilst the Valvoline Zerex G-05 in the USA is an HOAT (Hybride OAT). Their make up - and the Valvoline ELC coolant as well - is different to the Caltex ELC.

[Graeme]

The operating temperature of my TD5 at the temp sender is 100-101 deg C when not doing any work and can quickly get to 105 going up a hill on the freeway and the ecu doesn't go into reduced-power mode until 121 deg. Therefore a pressurised container would be required to do any testing.

[dobbo]

Mixing coolants can lead to reactions and changes in pH of the solution.


How much is the PH changed by? Is it changed to an alkaline or acidic state, if acidic is it enough to corrode alloy heads or eat through gaskets?

Are pre mixed coolants neutral in PH balance? If not what is the correct level to use.

All these questions


And all the public is told is use LR brand OAT coolant.

[dobbo]

The operating temperature of my TD5 at the temp sender is 100-101 deg C when not doing any work and can quickly get to 105 going up a hill on the freeway and the ecu doesn't go into reduced-power mode until 121 deg. Therefore a pressurised container would be required to do any testing.



Well thats me out for the testing then. Unless some has an Autoclave or something they can loan to me.

[dmdigital]

Correct. You would need to do a pressurized test at varying temperatures and also look at static state and flowing coolant.

How much is the PH changed by? Is it changed to an alkaline or acidic state, if acidic is it enough to corrode alloy heads or eat through gaskets?

The O.A.T. coolant is around pH 8-8.7 by design. As the coolant is consumed this would change with time, also I don't know what effect the temperature has on the pH of the operating coolant. The other thing that will affect mixing coolant is the additional additives, these may react and also change the coolant makeup.

Are pre mixed coolants neutral in PH balance? If not what is the correct level to use.

No O.A. T. coolants are alkline prior to dilution. the LR recommended Caltex ELC is pH 8.3 at 50% dilution with demineralized water. (I'll confirm this with a sample of the CAT ELC I have, if I get the chance)

And all the public is told is use LR brand OAT coolant.
And Holden drivers are told to use Holden coolant, Toyota to use Toyota Coolant, Ford - ford etc. Interestingly not all seem to be told to use an OAT coolant, just the "red stuff" (to quote a Toyota Dealer's parts person).

[abaddonxi]

Well thats me out for the testing then. Unless some has an Autoclave or something they can loan to me.


Perhaps something like a pressure cooker - runs at about 16psi - and an aluminium can and two types of coolant, and another run with some copper.

I'd suggest a stainless steel pressure cooker.








And if you ruin it it'll set you back about $250 for a new one.:D

Cheers
Simon

[dmdigital]

If I get a chance I'll run it all past a few Chemical specialists at work and see what they make of it all.

I know I haven't got access to a pressurized heated fluid system because I was discussing this with a colleague last week for some work trials. I'll try and check the pH next week and will post what I find. I'll also be able to see what effect a simple mix of the new and old coolants does (old coolant is 4y.o. LR original).

[GrahamH]

I'd like to expand the discussion a little if I may and ask what thoughts people have about the use of de-ionised (de-mineralised) water as opposed to distilled water as well as the additives.

I notice that several posts quoting manufacturers' recommendations have referred to de-ionised water and none to distilled water.

I have been told that de-ionised water is corrosive in aluminium block engines and the comment below about avoiding immersing electronic pH meter probes in the water lends this some credence. I do, in fact use de-ionised water with a Castrol additive (I can't find the bottle right now) in the Disco's V8 engine and in my Rangie's before that.

There's quite a bit of argument on the Net about this if you Google the subject (to use one of those horrible new American verbs obviously invented by a J**p-owner). Is there an argument about which is best amongst Land Rover owenrs as well, I wonder?

A good summary of the properties of de-ionised water comes from the web-site answers.com (slightly edited to remove irrelevant references and US spellings)....

“Deionised water … is water that lacks ions, such as cations from sodium, calcium, iron, copper and anions such as chloride and bromide. This means it has been purified from all other ions except H3O+ and OH−, but it may still contain other non-ionic types of impurities such as organic compounds. This type of water is produced using an ion exchange process. Deionised water is similar to distilled water, in that it is useful for scientific experiments where the presence of impurities may be undesirable.

Properties
The lack of ions causes the water's resistivity to increase. Ultra-pure deionised water can have a theoretical maximum resistivity up to 18.31 MΩ•cm, compared to around 15 kΩ•cm for common tap water. Deionized water's high resistivity allows it, in some very highly specialised instances, to be used as a coolant in direct contact with high-voltage electrical equipment. …

pH values
In theory, deionised water doesn't have a pH value, but in practice, it is usually considered by convention to be pH 7.0. pH is a logarithmic measurement of relative ion presence. Since there are no ions, there is nothing to measure. In practice, both chemical pH measuring systems and electronic pH meters will indicate a pH value. The indication from chemical indicators can give a value of usually between pH 5.0 and pH 9.0 depending on the indicator used (the indication being the ions introduced by the indicator itself, its solvent and its impurities). Electronic pH meters will indicate a random value since there is no conductance path to the electrode, but they should not be immersed in deionised water as the lack of any ions 'sucks' them out of the electrode degrading its performance.
Deionised water will quickly acquire a pH while in storage. Carbon dioxide, present in the atmosphere, will dissolve into the water, introducing ions and giving an acidic pH of around 5.0. The limited buffering capacity of DI water will not inhibit the formation of carbonic acid H2CO3. Boiling the water will remove the carbon dioxide to restore the absence of a pH value.”

So – is de-ionised water corrosive or not? I happen to have a small de-ionising water treatment machine made surplus when we de-commissioned a 50KW radio transmitter in the Territory. I’m relying on your opinions now, to tell me if it’s of any real use to me!

[DEFENDERZOOK]

The operating temperature of my TD5 at the temp sender is 100-101 deg C when not doing any work and can quickly get to 105 going up a hill on the freeway and the ecu doesn't go into reduced-power mode until 121 deg. Therefore a pressurised container would be required to do any testing.




isnt the coolant an antifreeze/ANTIBOIL.......?
it should raise the boiling point beyond 100 degrees.......so a simple open container should suffice.......

methinks......

[dobbo]

isnt the coolant an antifreeze/ANTIBOIL.......?
it should raise the boiling point beyond 100 degrees.......so a simple open container should suffice.......

methinks......


Doesn't de-ionised water have a higher boiling point due to the lack of impurities in it?

[dmdigital]

Isn't 100C the boiling point of pure water?

Also as you increase pressure you change the boiling point.

[dobbo]

Isn't 100C the boiling point of pure water?

Also as you increase pressure you change the boiling point.


yes this is correct, I meant when mixed with the antifreeze compared to a tap water and antifreeze mix.

What pressure is the cooling system working at and what is the boiling point in the radiator.

[dmdigital]

What pressure is the cooling system working at and what is the boiling point in the radiator.

2 very good questions :ohyes:

I was thinking that when I did the last post. I've never really measured a radiators running temperature. Now I have RCL I can actually capture the coolant temperature so I might run a little test when time permits.

As for pressure it can't be too severe. I don't suppose there's a pressure rating on the coolant reservoir cap?

[byron]

As for pressure it can't be too severe. I don't suppose there's a pressure rating on the coolant reservoir cap?

It's always been 14 or 16 psi;) [except on the earliest Series, as I recall;) ].....marked on caps;) ......might be in ATM.s or k.Pascals now:( , I suppose:(

[Graeme]

It's always been 14 or 16 psi;) [except on the earliest Series, as I recall;) ].....marked on caps;) ......might be in ATM.s or k.Pascals now:( , I suppose:(

Mine's 1.4Bar - approx 20psi, but I can't remember the formula for what the boiling point is at that pressure.

[Captain_Rightfoot]

Mine's 1.4Bar - approx 20psi, but I can't remember the formula for what the boiling point is at that pressure.
Here (http://www.engineeringtoolbox.com/boiling-point-water-d_926.html) you go... 14psi gives you 120 degrees boiling point on it's own :)

[JDNSW]

........

I'd suggest a stainless steel pressure cooker.


An aluminium one would be OK provided you put the coolant in a separate container (cut off aluminium drink can for example) supported above the bottom on the rack (and don't forget to put water in the bottom). A typical pressure cooker could have about three or for test samples in separate containers.
You should be able to find an aluminium one at any second hand or OP shop for a few dollars, just make sure the seals are in reasonable condition.

John

[ak]

Afyer many enquiries over the past week, ith L/R specialist from Brisbane to Sunshine Coast and Direct to Land Rover, They have indoicated the following

1/ Completely flush the cooling system
2/Use a Preferred Land Rover brand or select alternative
3/ Colour means nothing
4/Refill using either tank water or demineralized water
5/Dont use tap water, particularly with the dams low and the minerals in the water
6/once filled , bleed the system
7/ top and drive normally.
8/ DONT MIX COOLANTS OF ANY TYPE

I have decided to use Valvoline GO5 which I hhave sourced from MR Automotive, which is recommended by Land Rover and other specialists.
Thats my slant on it all
I hope that is of help
David Kemp
S11 TD5 Disco
S1 V8 Disco SE
S111 SWB

Graeme Coopers pretty much said the same thing. They use the penrite green stuff and they said to me everyone reckons you can only use the OAT red stuff-not true. They service a sh*t load of TD5's and not had any problems. They were more concerned about competely changing the coolant every 12 months or 20,000 k's.

[Lionel]

I can't see that the TD5 should be greatly different to any other modern engine with aluminium head and cast iron block. All these engines will be quickly ruined if corrosion inhibitors are not used in the coolant.

I have always used Castrol Antifreeze Antiboil with previous cars, and never had any problem with corrosion. Most of these had aluminium/cast iron engines.

The important thing is to change it every 2 years max., and to flush everything out very carefully when you change it.

I am sure the Penrite, Castrol or any brand supplied by reputable oil companies (:D) would be OK.

Cheers,

Lionel

[chazza]

"The important thing is to change it every 2 years max., and to flush everything out very carefully when you change it."

Not sure about the TD5 engined cars, but on my 3.9 Disco, the manual says that flushing the heater is undesirable. I suspect that this might be because of difficulty getting the air out later; therefore, LR say to refill with the same coolant they use, so as not to mix types.
cheers Chazza

[DEFENDERZOOK]

"The important thing is to change it every 2 years max., and to flush everything out very carefully when you change it."

Not sure about the TD5 engined cars, but on my 3.9 Disco, the manual says that flushing the heater is undesirable. I suspect that this might be because of difficulty getting the air out later; therefore, LR say to refill with the same coolant they use, so as not to mix types.
cheers Chazza

when i flush out my cooling system....thats where i stick the hose......
i remove one of the heater hoses....turn the heater on......and stick the garden hose into the heater hose......
and flush..........

[George130]

when i flush out my cooling system....thats where i stick the hose......
i remove one of the heater hoses....turn the heater on......and stick the garden hose into the heater hose......
and flush..........


Thats what I do.

[shaunp]

I put Valvoline GO5 in everything 50% mix, works fine, alloy looks like new when you pull the engines a part. I think that's all M.R use

[feraldisco]

just resurrecting this thread re ph value of coolant. The doc in the below link reckons min ph of 8.3. I've just checked the coolant ph on vehicles with relatively new 50/50 glycol and one with no glycol but corrosion inhibitor and water wetter - both are close to neutural - surely neutral ph can't be any more corrosive than alkaline?

http://www.eutechinst.com/tips/general/05.pdf

[Milton477]

Summer must be around the corner, just not in Brissy this week.

[feraldisco]

this article sheds a bit more light on the matter and it looks like I better replace my coolant...

ARE Cooling (Aluminium Radiators & Engineering P/L) (http://www.are.com.au/feat/techtalk/coolants.htm)

[Ferret]

Maybe the rest of the info in that article is correct but that first item on the wind chill factor is crap.

"As you can see from this chart, if a vehicle was parked in an area where the surrounding air temperature was 0 Celsius and a wind of say 24 km/h came up, blowing directly through the radiator, the propensity for the cooling fluid to freeze quickly is drastically accelerated.

Wind chill needs to be considered in colder areas of Australia."

Wind alone can't lower the temperature of the radiator below the ambient air temperature.

[scott oz]

Having no technical knowledge :oI did some research two/three years ago and there was a raging debate on one of the Landrover UK forums on coolants; including a couple of researcher & academic types.

One comment that seems to be often misquoted is Antifreeze raises the boiling point or contains inhibitors or aids in cooling.

It seems to me that a property of a COOLANTs is (1) anti freeze (2) corrosion inhibitors (3) water wetters.

The most fundamental purpose of coolant is aiding in the heat transfer process. That is getting heat out of the system primarily via the radiator.

One of the most common anti freeze additives “glycol” in actual fact inhibits the coolants ability to absorb heat in this process. Something about the glycol molecules. But it does lower the freezing temperature. That’s what it’s there for.

Inhibitors are there to neutralise corrosive reactions within the coolant system.

“Water wetters” are there (my interpretation) to break down the molecular bonds in water which aids in heat absorption.

The conclusion of the thread was the best coolant “cocktail” was a “water wetter” with inhibitors. This was chemically the most efficient heat transfer coolant mix.

“If” you live/visit etc a place where water will freeze then you need to add in an anti freeze product to the coolant like “glycol”.

One of the most common water wetter’s around is the products made by Red Line. They make one with inhibitors and one without.

The comments on making sure the coolant system is property pressurised is a major factor in raising the boiling point of coolant. I think the pressurising of the system is the primary ingredient in raising the boiling point, as opposed to any of the other additives/components of the “coolant”.

For what its worth that’s my plain English non tech reading of the issues.:)

[Ace]

After the kids finish Year 10 School Certificate exams they have finished their work for the year. As a result a couple of years ago i was looking for pracs to do with the kids in science to keep the motivated and occupied for the remainder of term 4. I had a similar thought to dobbo and I thought i'd test if changing the concentration of the coolant in the water would affect the boiling point.

Now its been a while since i did it but with 50:50 coolant to water the mixture boiled at about 108 degrees celcius. This boiling temp would be increased again in a pressurised container such as an engine cooling system.

Im doing a bit of casual teaching at the moment so next time im out at school i'll do another one in the science lab. it wont be in a pressurised container but i might even be able to test a couple of different brands aswell.

Matt

[feraldisco]

Scott's post pretty much sums up what I've been told. It makes you wonder how much better vehicles would run, reduced corrosion problems (through degraded/acid by-product of glycol breakdown) and reduced overheating problems there would be if everyone just ran water and Redline waterwetter (with the corrosion inhibitor package). Given that Natrad in Canberra don't reckon antifreeze is necessary (unless going to the snow), why the heck would anyone in Nth Qld, or most of Oz for that matter, use antifreeze with all its associated problems (reduced cooling, corrosion from acidification, toxic waste etc). Seems to me that antifreeze is a North American/European invention that is best left to such climates... All the discussion on this forum about OAT vs HOAT vs conventional glycol seems to be missing the point - best to get rid of all of them!