Originally Posted by djerickd
Well water boils at 100 ºC/212 ºF and methanol boils at 64.5 ºC/148 ºF, I wonder if you were smelling it cooking!
I was still seeing the same pressure and performance from the system which leads me to believe that it was not close to saturation temperature (temperature a given liquid will boil at a given pressure). If it was starting to actually boil there is good chance it would flash instantly in the pump suction (lower dynamic pressure) and the pump would not pump. Yes I know that methanol will boil at 148F (at sea level) but I also am aware of the fact that it takes EXTRA energy to convert a liquid to vapor than just what you can read on a thermometer. Can you have water at 212F at sea level? Of couse if you only apply enough energy to heat it to that point (it will of course cool off) but not enough to cause a phase change. Also under atmospheric conditions and under normal real world conditions it would take much more thermal energy to raise 1lb of water to 1lb of water vapor than one would think considering the btu's definition. This is due to the fact that some of the water will evaporate, converting specific heat to latent heat during the phase change. I was less worried about it "cooking" than I was it just evaporating. Even if a liquid is not boiling it can still evaporate (cooling towers as an example), methanol evaporating and filling the engine bay is bad. Even if you mix methanol with water it will still reach saturation temperature at the same point, you haven't changed the chemical properties by adding water. Although water has a much higher specific heat than methanol as well as taking much more latent heat to phase change.