Flathead Coolant

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Just curious as what most run in their flatheads for coolant/water pump lube. Distilled water with 50% antifreeze or distilled water and some brand of water pump lube or just water?
 
I did a search and read all that but am interested to see if everyone is still thinking the same way.
 
I run 50/50 with distilled water. The water pump builder I use (Skip Haney) recommends water wetter but I hadn't found it necessary for either of my cars to run within acceptable boundaries.
 
One additional note that's related but not what you asked about.

My car's cooling systems will hold 5 gallons. My note... Be prepared with adequate storage for the fluid you will be draining.

I have a 35 and a 36. Both cars engine replaced with 1937 block using water pump block off plates with pumps in the (original-ish) 35 and 36 heads, the radiators are appropriate for the cars. My 35 has the small-top rad, and the '36 has the huge expansion area at the top.
 
I am "another fan" of distilled water with propylene glycol. That is what I have in my '34 pickup and '37 dump truck.
 
I just ordered No-Rosion and they recommend the use of purified water if using straight water as a coolant, not distilled. Here is what they say.

Should I use distilled water as coolant?

A. Yes. But only in a 50/50 mix. Distilled water should not be used as straight water coolant, because it can cause damage to system metals. The reason has to do with how distilled water is created.

During the distillation process, water is vaporized into its gaseous phase, so all impurities are left behind. These impurities include a number of minerals, including calcium and magnesium, the two components of hardness. The water is then condensed back into its liquid phase, so the resulting liquid is pure water. In fact, some of the purest water on earth. The problem is that distillation strips impurities from water, resulting in water molecules that are electrochemically imbalanced. So distilled water will actually strip electrons from the metals in a cooling system as it attempts to rebalance itself electrochemically. This can result in damage to metals in a cooling system.

Using distilled water in combination with 50% antifreeze effectively cuts the amount of distilled water in half. By compounding with glycol, it will not cause damage to metals in a cooling system. For this reason, it is safe to use distilled water in a 50/50 mix.

Q. What type of water is best to use as straight water coolant?

A. Reverse osmosis (RO) water. Rather than stripping impurities from water, RO filters them through a membrane. The resulting water is electrochemically stable, and not harmful to metals in a cooling system. RO water is every bit as pure as distilled water, but without the risk of electrochemical stripping of electrons from system metals.

Q. Where can I find reverse osmosis (RO) water?

A. At the local supermarket. Look for DRINKING WATER, which is available in gallon bottles. But do not confuse it with SPRING WATER, which is often high in mineral content. We have performed extensive testing of major brands and generic brands of bottled drinking water, and found that it is almost always composed of RO water.

Q. What are the benefits of using purified water, such as distilled or RO?

A. It lacks the impurities of tap water. Without impurities, its ability to function as an electrolyte is greatly diminished, thereby minimizing damage from electrolysis. It contains no hardness, meaning it will not form scales and deposits that can cause overheating. It does not contain other damaging contaminants, such as chloride or sulfate. And importantly, it enhances the overall performance of No-Rosion, allowing it to more effectively function and provide the full range of benefits that it has been engineered to provide.
 
33/67 mix antifreeze/summer coolant and water. It doesn't get too cold here. I just use tap water but the water here is nice "soft" water from Wales. Nothing else. I just use what millions of everyday motorists use.
 
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Thanks to all and especially Tim for his education on the different types of water. Very interesting and good to know.
 
I have been running a mix of 60% ethylene glycol and 40% water In mine since 1985 after restoration and replace every 7 years . No issues.
A few year ago , I even removed the intake manifold and looked around. Still looks great.
Vic
 
I learned with Paul Garigan aka Rumbleseat that only destilated water plus an anticorrosive like Wynns is the way to keep away from overheating. Etylene glicol based products will retard the heat transfer in a flathead. I did it and never had any issue again, and got 180° stats.
 
every set up is different these days with the use of alloy rads alloy heads stainless or alloy piping that all changes what is required of your cooling system also your water supply can vary from what could be call liquid rocks[ very high mineral content] to near perfect rain water and even that can vary from acidic to alkaline personally i just go for a quality premix
 
51er said:
I learned with Paul Garigan aka Rumbleseat that only destilated water plus an anticorrosive like Wynns is the way to keep away from overheating. Etylene glicol based products will retard the heat transfer in a flathead. I did it and never had any issue again, and got 180° stats.
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For those of us with engines that are prone to overheating, the 17% difference in heat carrying capacity between water and ethylene glycol make the difference. Replacing the pretty Champion aluminum radiator with a truck radiator (it fits) in my '41 coupe made a big difference; dropping from 50/50 to 20/80 antifreeze/water mix got me through the really hot days in traffic. 20/80 only protects to 16F, but that is fine for my area and a car that is always garaged with a little heat.
 
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