I just KNOW I'm going to get in bother from Slob for this .. I just know it!
But what the Hell?
The problem with antifreeze is not so much the freezing.
It is because antifreeze (ethylene glycol - the real stuff) is not nearly as good as WATER for carrying HEAT energy. Alcohol (meths, methanol etc) too.
For instance,
to raise the temperature of a litre (or kilogram) or water by one degree C requires you to add 4,200 Joules of heat ebergy to the water. Just think 4,200.
To do the same to a kilo of alcohol needs only 2,500 Joules.
Glycol I can't find the figures for but I think it will be about HALF that of plain water. So .... if the engine heats up a lot, it will heat up about twice as fast on alochol or neat glycol as it will using plain water, AND it will take the coolant twice as long to carry the heat away as it would using plain water.
Plain water has an exceptionally high specific heat capacity. It is in a class of its own, which is very handy for us who use internal combustion engines that are liquid-cooled.
In the arctic, and in piston engine planes that go to high altitudes, they can use neat glycol coolants because it is so cold outside (-40C/F) that the glycol will cool the thing fine, as in arctic vehicles.
You might be surprised that the Specific heat capacity of metals is very low compared to water, weight for weight about one tenth! A kilo of lead needs 140 Joules compared to 4,200 for water, copper is about 380, and steel or cast iron in the same league. It's why air-cooled engines heat up so very quickly, but a liquid cooled one takes so long.
Sorry Slob .....
CharlesY
