Reply To: Waterless Coolant

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Hi Richard,

You are referring to Evans waterless coolant, which is nothing more than pure ethylene glycol antifreeze (with no water in it). The anti-corrosion and anti-boiling properties are excellent and beyond reproach, but the cooling leaves something to be desired, in my opinion.

Ethylene glycol has only 70% of the heat-carrying capacity of water. So your engine will run about 20-30% hotter than with water. This can have several effects:

(1) With the higher volatility of today’s gasoline, and the already present propensity toward vapor lock, the car will vapor lock at slighter provocations – ambient temperature over 70*, altitude over a thousand feet, hill climbing, etc.

(2) You will be anxious seeing your temp gauge liquid at the top of its range all the time.

(3) If your engine has valve seat inserts, the higher operating temperature could shorten their life – they may start loosening up prematurely due to wider temperature cycling range.

I try to run my cars at the lowest practical temp – heat is the enemy.

Water is THE best cooling liquid. You can add additives for corrosion protection (Nalcool, Pencool, etc.) and drain the block for storage times.

Running a 50-50 antifreeze/water mixture will cool better than pure Evans (but worse than pure water) and have some corrosion protection, but may foam in your Pierce.

The one area that pure ethylene glycol will cool better is in areas in the block that tend to have low flow rates, and the coolant lingers in a hot spot until it boils at that spot (even though the average block temp is OK). These mini-boiling areas then get even hotter since there is only steam contact, and can damage valves and seats, etc. The Evans coolant will not boil at these spots.

Evans would be ideal if the water pump and radiator were designed for it – with a 30% greater flow rate and radiating surface – so the engine would operate in the temp range it was designed for.

(There is an argument that engines operate more efficiently at higher temps, but I haven’t researched it.)

That being said, I know Restoration Supply (Escondido, CA) sells it for $35 a gallon. (I tried some in my ’38 Buick.) You can order some and try it for yourself. I bought a higher flow radiator core for my ’33 and when I install it I may try Evans again.

Regards,

Bob