At 05:26 PM 4/5/2012, Austin wrote:
>What about just running a very light 0, 5 ? weight mineral or motor
>oil or transmission fluid ???

It would be a real mess, maybe find leaks that are too small for
water to go through, likely rot the hoses, water pump seal, head
sealing gasket and such.

That being said, here's a "heat transfer fluid" that's meant to
replace glycol solutions.  It might or might not require a
higher-capacity water pump, as its specific heat is less than either
the 50% glycol or Evans' glycol solution.  And without asking the
company I couldn't promise it would be compatible with the rubber
components.  But it's food grade!  May cost a fortune, of course.
http://www.paratherm.com/Paratherm-LR/Paratherm_LR_Ethylene_Glycol_Propylene_Glycol.asp

Yours,
David