By Randy Rundle

   Those of you who own and drive antique and classic cars (especially in parades) are aware of the potential of the cooling system to overheat. This is often caused by a number of things including poor air circulation, poor coolant circulation and high temperatures on high-humidity days. Regardless of the cause, you would think that, after so many years, someone would do something to improve the situation.

   Well, somebody finally has! While doing research for my new book, Cooling System Basics  (due out in the spring of 1999 from Old Cars publications) I discovered a company called Evans Cooling. They have developed an engine coolant that is not mixed with water.  It has a boiling point of 370 degrees and gives freeze protection to minus 80 degrees.  The best part is that is designed to work in a non-pressurized cooling system.

   I immediately thought of all the antique vehicles built before 1950 with non-pressurized cooling systems and wondered if this new coolant would work in them.  Could the boiling point really be that high without a pressurized cap?

   From my research I knew that water – while one of the best dispersents of heat (the molecules in water are spaced far apart) – is one of the most corrosive things you can put into a cooling system.  Conventional, ethylene-glycol-based antifreeze, contain additives to correct the pH-balance of the water, so that it does not turn acidic and allow corrosion to form inside the cooling system (lime and mineral deposits for example).

   Antifreeze also contains additives to help prevent “electrolysis,” which occurs when a conductive solution such as water, passes over the dissimilar metals that make up a cooling system.  Electrolysis can attack rubber cooling system hoses, as well as destroy metal surfaces (like the core of the radiator) and cause a leak that makes the cooling system fail.

   Through the mid ‘70s, most antifreeze contained silicate additives which were abrasives that kept the mineral deposits, in the water, from building up in the cooling systems.  Because the silicate additives were abrasive, they also destroyed water pump seals.  A water-soluble oil was added to the antifreeze solution to protect the water pump seals.  This oil was called water-pump lubricant.

   If you used straight water in your cooling system during the summer months (distilled water worked best) you also had to add a pint of rust inhibitor/water pump pump lubricant to the water.  Now you know why.

   Of course, if there was a way to eliminate the water in the coolant, all of the problems associated with water would disappear as well.

   In conventional antifreeze, as the additives wear out, the pH of the water begins to turn acidic.  This is why it is necessary to flush and replace your antifreeze-coolant at least every three years, even if your car is in storage.  Like the additives in engine oil, the antifreeze additives wear out just being in the water, whether or not you drive the car.

   To replace water, you need something that is able to transfer heat as efficiently as water.  Antifreeze solutions provide almost no cooling benefits, since the molecules in ethelyene-glycol antifreeze solutions are very close together.  The solution only carries the additives that correct the pH, and the water soluble oil.  Together, these do provide freeze protection, so be sure your old car is protected in the winter months.

   Knowing what anitfreeze and water based coolants are supposed to do, and knowing what properties a replacement solution has to have, the last step is the addition of pressure.  Prior to 1955, most automobile cooling systems were of the non-pressurized type, which meant that the coolant would boil at or before 212 degrees F. (Water boils at 212 degrees F. at sea level.)  The higher the altitude, the sooner the water boils.

   When water begins to boil, steam forms.  This tells you that water is saturated with heat and cannot accept any more.  When steam pockets form in a cooling system, they can also build up a barrier and block the flow of fresh coolant through the system.

   Finally, the water pump – if the engine has one – will begin to pump air, causing the coolant to foam.  This causes the coolant to accept more air, and reduces the cooling ability of the coolant even further.

   Modern cars, like many of those built after 1955, started using pressurized cooling systems.  The benefit was that, for every pound of pressure created in the cooling system, the boiling point of the water was raised by three degrees.  By sealing up the cooling system, and adding pressure, the boiling point of the water was raised.  Then, the engine could be operated at a higher temperature and operated more efficiently.  Today, most modern cars use a 16-lb. cap to raise the boiling point 48 degrees higher than the normal 212 degree boiling point.

   All of this is well and fine for newer collector cars, but the older cars of the ‘20s and ‘30s didn’t even have water pumps.  They depended strictly upon the expansion of the coolant itself to force coolant to circulate through the system.  What are the owners of such cars supposed to do today?

   After reading and studying the information about the Evans coolant I determined that it would probably be ideal for vintage-and-classic-automobile cooling systems.  Its biggest advantage seemed to be getting rid of water, which caused all sorts of problems with corrosion and electrolysis.  No water meant no changing antifreeze every two or three years.  It also meant no more electrolysis attacking rubber cooling hoses.  And because the boiling point was 370 degrees, the chance of losing coolant was greatly reduced.

   I figured if a coolant didn’t boil, less vapor pockets would be formed, improving heat-transfer efficiency.

   Since this seemed too good to be true, I called Evans and talked to Steve Pressley.  He provided tons of data and tests proving this coolant worked in the real world (it had been around since 1983).  I said I wanted to know how much experience Evans had with ‘20s vintage cars.  One thing led to another, and I was able to get Evans to sponsor a car in The History Channel Great American Race.

   Rex Gardener and Gary Kuck drove a ’17 Hudson Indy Speedster in the 1998 race.  The race route is about 4,000 miles long.  The cars run in all types of weather, at all different, in all kinds of temperature and humidity conditions.  If Evans coolant survived in the Hudson’s cooling system, I would be convinced.

   The coolant worked well.  To prevent loss of coolant, the Hudson’s cooling system was pressurized using a 5-pound cap.  This created enough vacuum to draw the coolant back into the engine after it cooled, in case any expanded into the overflow tank.

   Amazingly, the Hudson never had a drop of coolant in the radiator overflow during the entire race, even in the mountains, at altitudes above 10,000 feet.  Higher altitudes make engines work harder, because the air is thinner and makes an engine’s compression pressure much lower.  This situation creates more heat.  At the same time, the coolant will have a lower boiling point, because of the higher altitude.  The Hudson tested the 370 degree boiling point of the coolant to the extreme.

   Rex Gardner and Gary Kuck won the Great American Race, taking both the Championship Class and the World Class for cars 1920 and older.  Gardner and Kuck worked hard, driving in snow, hail, and pouring rain for days on end.  It was an outstanding testament to their driving and mechanical skills to win the race driving a car that is over 80 years old.

   While it was originally designed for modern racing applications, it seems the Evans’ coolant can be of great benefit to all antique and classic car owners, especially those with vehicles having older, thermo-siphon cooling systems.  Even modern muscle cars may benefit from the added boil-over protection.  For more information contact:  Evans Cooling Systems at 255 Route 41 North, Sharon, CT  06069.