Thread: Coolant for 300tdi, non glycol type??

I tried this stuff in my RRC with a p76 V8, on dual fuel and with an alloy radiator and thermo fans. Never overheated, never had a problem. Race cars use it because it evaporates on the track if you have an off moment. I guess with a landrover it would evaporate when it leaks out of the P gasket too!

I suppose on newer vehicles which run higher cooling system pressures (and therefore temperatures for efficiency and emissions) you would need the anti-boil characteristics of glycol. Or if you venture to the snow/cold climates. But on a 300TDI which doesn't see those climates.. I guess you could run it?

Don't stuff with the cooling system,overheating is the standout number one killer of LR engines,Only use Glycol coolant,Nulon is good,I use Texaco extra cool gold and none other.Don't experiment with the cooling system. Pat

With aluminium alloy components, the anti corrosion aspect of coolant is very important. However, from what I gather, if you don't need anti freeze, don't use it. Apparently ethylene glycol is less efficient for transferring heat than straight water. I think it is the component of some coolants that leaves a film of low conductivity on surfaces inside the radiator, block, head etc which also reduces efficiency of heat transfer.


Note how recommendations of what proportion of anti freeze to use is often for conditions in countries with much colder winter temperatures than ours. eg I recall that 33% ethylene glycol will protect down to minus 18 degrees. Also a comment from a machinery operating contractor in a Victorian Alpine area where it snows in winter that you don't need much. Probably very rarely gets down to minus 9 and usually temps are warmer during the day. In Australia, best to find what straight anti corrosion coolant is compatible with coolant / anti freeze solution used. Another reason for not using more anti freeze than necessary is that it is expensive.

I'm pretty sure it's the glycol that increases the boiling point too isn't it? What is the boiling point of the other stuff? I would guess it has something in it too and that's important. A TDI can run at coolant temp over 100*C and still be considered normal and safe.

The temperature at which water - and other liquids boil depend on the air pressure. At sea level this is about 15 psi and water boils at 100degrees Celsius. At high altitudes is lower than this. \The purpose of having pressurised cooling systems, eg with radiator caps which blow at 10 or 13 psi is to allow the motor to run a bit hotter without losing water. If you release pressure, water boils away until temperature of that remaining drops to 100 degrees. Producing steam or water vapour, which air at under 100% humidity will hold takes about 5.4 times the amount of heat required to heat the same amount of water from just above freezing point to just below boiling point. ie Latent Heat of Vaporisation.

A disadvantage of ethylene glycol solution compared with straight water is that it has lower Specific Heat, which makes it less efficient for heat transfer. ie It takes more heat to raise the temperature of water than it does to raise that of the same weight or volume of ethylene glycol.

It seems you have a good point. I thought the increased boiling point was a combination of an anti-boil additive and pressure, but I just looked it up and water @ 15psi boils at 121*C. More than enough and is roughly what I thought the boiling point of coolant is.

x2 on ethylene glycol has lower Specific Heat.

I was thinking as Mox, pressure system allows higher boiling. The alcohol stops freezing at zero. TV program (Muscle Car?) they used demineralised water with alloy head (and block?) - although they said it was just in case of spillage at the race track, no green residues under foot - no comment about long term use. I have seen arguments about merits of anti-corrosion additives, some swearing by it and others going demineralised only.