rad and coolant, TPEFI related

[Terry Martin]

George M. Dailey wrote:
> 
> I think you mised the reason why he had to use straight ethylene glycole. As
> I understood it, this was the only liquid (reasonable) that had a vapor
> pressure low enough at the required operating temperature to permitt normal
> engine gaskets to hold. I don't know the actual conditions. But, unique
> applications require unique solutions. Did you know that some nuclear
> reactor are cooled with molten elemental sodium!
> 
> GMD
> 
> At 01:42 AM 10/22/97 -0400, you wrote:
> >George M. Dailey wrote:
> >
> >> engine temp of 250 or 300F, I think. The main problem was he had to use 100%
> >> pure ethylene glycole with no water what so ever. Water would flash to steam
> >> and create abnormally high radiator pressures.
> >
> >The problem I see with that is the the water/coolant mix is much more
> >efficient at transferring heat than just coolant alone. Another option
> >is to build a good, strong cooling system that can take 25 lb pressures
> >like the race cars, and use the optimum coolant/water mix...

Hmm, I'll have to check my chemistry, but I understood it was the
addition of water to the coolant that lowered the vapour pressure. The
water does not remain simply H2O, but combines with the coolant to form
a different chemistry, lowering the vapour pressure. It also lowers the
freezing point, something that any good rad man will confirm. Straight
anti-freeze gels at low temps unless it's combined with water at
whatever spec the specific product requires.

Terry