Thread: Demineralised or distilled for radiator

disco gazza: The coolant you are using is 1 of 2, i can't say for certain which one it is without seeing it, so i'll give you a run down on both. They are:

• Corrosion Inhibitor Concentrate which comes in 200ml bottles. This is as the name says, a corrosion inhibitor only. It contains virtually no anti-freeze/anti-boil properties, and is only designed to prevent the cooling components from corroding away (it is designed to be added to your cooling system in addition to another coolant). I would not recommend using this on its own.
• Anti-Freeze/Anti-Boil Concentrate, which comes in 1L bottles and up. This also contains corrosion inhibitors. This is a Anti-Freeze/Anti-Boil Ethylene Glycol based coolant, it contains no silicates and is safe for alloy components. This coolant needs to be used at 50% dilution in turbo diesel engines. It is a reasonably good value for money coolant, it isn't the best coolant on the market but still more than suitable for the job.

My recommendations would be either Repco Organic Long Life or Nulon Red Long Life. Both of these are OAT (Organic Acid Technology), they are both Ethylene Glycol based, and are both free of harmful additives making them suitable for all modern engines including all alloy and rubber components. These must be used at 50% dilution in TDi's, and i would also recommend it in the V8's to help keep them cooler. I make both of these coolants. I have done Laboratory testing on almost all coolants available in Australia, and these come in very high on the list.

As a general rule of thumb Red coolants are OAT (which is for modern engines) and Green coolants are designed for older cast iron engines. Please only use this as a guide as it is not always the case.

superquag: As you can see above i have given my recommendations of 2 of the better coolants suitable. I use the Repco in my own TDi Discovery, and i have a good mate that uses it in his V8 Rangie. Any further questions feel free to reply or send me a PM.

I run distilled water mixed with glycol free Nulon Ultracool and a bottle of Redline water wetter in the V8.

Originally Posted by par10

disco gazza: The coolant you are using is 1 of 2, i can't say for certain which one it is without seeing it, so i'll give you a run down on both. They are:

• Corrosion Inhibitor Concentrate which comes in 200ml bottles. This is as the name says, a corrosion inhibitor only. It contains virtually no anti-freeze/anti-boil properties, and is only designed to prevent the cooling components from corroding away (it is designed to be added to your cooling system in addition to another coolant). I would not recommend using this on its own.
• Anti-Freeze/Anti-Boil Concentrate, which comes in 1L bottles and up. This also contains corrosion inhibitors. This is a Anti-Freeze/Anti-Boil Ethylene Glycol based coolant, it contains no silicates and is safe for alloy components. This coolant needs to be used at 50% dilution in turbo diesel engines. It is a reasonably good value for money coolant, it isn't the best coolant on the market but still more than suitable for the job.

My recommendations would be either Repco Organic Long Life or Nulon Red Long Life. Both of these are OAT (Organic Acid Technology), they are both Ethylene Glycol based, and are both free of harmful additives making them suitable for all modern engines including all alloy and rubber components. These must be used at 50% dilution in TDi's, and i would also recommend it in the V8's to help keep them cooler. I make both of these coolants. I have done Laboratory testing on almost all coolants available in Australia, and these come in very high on the list.

As a general rule of thumb Red coolants are OAT (which is for modern engines) and Green coolants are designed for older cast iron engines. Please only use this as a guide as it is not always the case.

superquag: As you can see above i have given my recommendations of 2 of the better coolants suitable. I use the Repco in my own TDi Discovery, and i have a good mate that uses it in his V8 Rangie. Any further questions feel free to reply or send me a PM.

The Tdi has a cast iron block so I would stick with ethylene glycol, I tend to use tank water rather than tap water. My '95 Defender is on it's original radiator and has never been rodded. coolant is replaced at the correct intervals.

I'm a bit confused by the comments regarding OAT coolants, I was under the impression that OAT and ethylene glycol coolants were completely different formulations but you're suggesting that there are ethylene glycol based OAT coolants. Once we get to HOAT's I'm really confused and then there are coolants that seem to be able to replace all of the above !

There have been a lot of problems reported using OAT coolants in older vehicles not designed for it. The main advantages of OAT seem to be the longer life but you clearly need to check it's suitable for your vehicle. If in doubt I would be using a traditional ethylene glycol based coolant and change it at the correct interval.

Colin

Par10,

Thanks for your input,much appreciated.
Time to go buy some Repco or Nulon and do the radiator.

cheers

Thanks for the info.

Does the Repco/Nulon Red Magic OAT fluoresce as nicely as the Green Stuff (glycol)

I use a UV torch at night to check over the hoses etc....green Nulon really jumps out at you

Any issues in changing from green to red ? - flushing with any particular cleaners etc of value,? Or damaging? - or just endless water changes?

Seems to be a little bit of confusion. All coolants are made up with a base of either Ethylene Glycol, Propylene Glycol or Demineralised Water, regardless of whether it is a IAT (Inorganic Acid Technology), OAT (Organic Acid Technology), HOAT (Hybrid Organic Acid Technology) or UFF (Universally Fully Formulated). For example, my company makes both Ethylene Glycol and Water-Based OAT's, Ethylene and Propylene Glycol IAT's, Ethylene Glycol HOAT's and Ethylene Glycol UFF's.

The style of coolant all comes down to the raw materials (additives) that are put into them, not the base on which they are made. Most OAT's contain no silicates, nitrates, phosphates etc, which is what makes them safe for modern engines. IAT's contain the above materials which are fine for cast iron components, which is why they are suited for older engines. HOAT's are a combination of both, and are generally safe for a majority of engines both new and old. UFF's contain very little in harmful additives, but are generally only designed for Heavy Vehicle use.

Never combine different coolants under ANY circumstances. While there is a very small number of coolants that are compatible, most of them are not, and can cause catastrophic failures. Flushing is easy regardless of what style coolant it is, the best way is just to use water, although there is radiator flushes available.

Both Ethylene and Propylene Glycol are used as a base for probably about 80% of all coolants made. This is because they offer excellent heat transfer properties, and when diluted to 50% they raise the boiling point to approx 108°C (up to 135°C when pressurised in a cooling system) and drop the freeze-point to approx -37°C.

Water is the most important component. Poor quality water is the cause of more than 90% of all cooling system issues worldwide. Rain water is okay to use, although Demineralised water is still the best option. NEVER use tap or bore water.

The reason most green coolants are so flourescent is because they actually contain flouroscein in the dye, while no other colours do.

Traco: The Nulon Ultracool you are using is a Water-Based OAT, which is made by us. It is a very good coolant, although because it is doesn't contain Glycol it doesn't have any Anti-Freeze/Anti-Boil properties.

I have used Nulon Longlife ( green) at 50% for the last 12 years with 2 year changes and distilled water.
I have NIL corrosion on any pipe stub or internal waterway or waterpump and after 11 years the radiator core was clean on rodding.

So although it may be best in older engines it certainly has been great in my alloy V8 .
I don't think I would go to the trouble of flushing and refilling with red with that result as IMHO it is a lottery whether I would get all of the old coolant out.

Regards Philip A

FWIW: In the P38, I use the long life stuff sold by Holden Dealers for LS1 V8. Demineralised water from the supermarket in 10L containers. Use a 50% mix. Replace every 4 years. Excellent results.