Evans Waterless Coolant

May 05, 2013 View Comments by

Evans Waterless Coolant“Waterless coolant? I knew it! Lamishaw has gone completely mental, totally around the bend, bonkers, off his bean. What are you supposed to put in the radiator, sand?” Calm down, relax, take a breath… it’s not as crazy as it sounds.

Evans waterless coolant is a liquid, but without any water. Why would you want a liquid coolant without water? I’m glad you asked. Water in coolant offers one very positive feature; it is a very efficient conductor of heat. However, water-based coolants also have a number of disadvantages: water has a fairly low boiling point (100-degrees Celsius or 212-degrees Fahrenheit) at sea level; water promotes rust; and water freezes at a fairly high temp (zero-degrees Celsius or 32-degrees Fahrenheit). To overcome some of these limitations, we use pressurized caps to increase the boiling point; add anti-freeze to lower the freezing temperature; manufacturers add rust inhibitors and other chemicals to help lubricate the water pump and prevent rust. All of these chemicals lose effectiveness over time, and so water-based coolants should be drained and replaced every couple of years.  In short, companies spend a lot of money coming up with ways to deal with all the shortcomings of water-based coolants. A company called Evans Waterless Engine Cooling took a different approach and developed a coolant that overcomes all these problems by eliminating the water.

Of all water’s limitations, the most serious, for motorbike riders, is its low boiling point.  Coolant is only efficient when it is in a liquid state. As a gas water vapor lacks thermal mass and thus is extremely inefficient as a coolant. The reason your cold-weather jacket keeps you warm is that the air pockets created by the insulation trap body heat. That is a good thing if you want to stay warm, but not if you need to take heat away. So, bubbles in your coolant are bad. Increasing pressure raises the boiling point, which is why radiator caps are pressurized. Think of a bottle of soda, when the cap is on, it’s a liquid; take the cap off, thus reducing the pressure, and the gas (CO2 in the case of soda, or steam in the case of coolant) comes out of the solution, forming bubbles. In our engines these bubbles form little pockets where heat from the engine, especially around the cylinders, can’t escape. This bubble formation is called cavitation and is very bad for your engine. Put another way, the goal of any cooling system is to keep the internal metal temperatures under control. This can only happen if the liquid is in contact with the metal to carry the heat away. The bubbles of a boiling coolant act as insulation, holding in heat and preventing the coolant from doing its job. When you combine the limitations of water-based coolants with the fact that high performance motorcycle engines run at very high temperatures, and often have limited radiator size and air movement capacity, you have a recipe for very high internal temperatures and engine damage. The advantage of Evans is that since it won’t boil until a much higher temperature (over 375-degrees Fahrenheit), there is more efficient heat transfer, largely because it remains in a liquid state and thus in contact with the hot metal of your engine. Some of the features of Evans Heavy Duty Coolant are:

  • Boiling point: 190.6° C (375° F), at zero psi
  • Freezing point: Below -40° C (-40° F)
  • Specially formulated for high-performance engines, like those found on multi-cylinder, water-cooled motorcycles.
  • Stops cylinder liner cavitation erosion (pitting of the cylinder liner wall).
  • Lasts the lifetime of the engine, if uncontaminated by water (you never have to replace the coolant).
  • Ends a condition known as “after boil.”
  • The cooling system develops less pressure because there is no vapor component, thus avoiding “boiling over,” or pushing coolant out of the overflow reservoir.

Converting from your current water-based system to Evans Waterless Coolant is not terribly complex, but you do need their prep fluid, as it is very important to get all the water out of the system. Basically, you drain the existing coolant, put in the prep fluid, run the engine for a few moments, drain the prep fluid, and repeat. Once you’ve done this you simply put the waterless coolant in, and that’s it. On some motorbikes, like my F 650 GS twin, one has to “bleed” the coolant lines to get all the air out of the top of the engine, but it’s not difficult though it is a bit tedious. Still, not having to ever change the fluid, not having overflow problems as the coolant expands, and seeing that the coolant doesn’t get as hot, even in stop-and-go traffic on hot days, is, in my opinion, well worth the effort.

It is also noteworthy that in tests on rats, none died after eating the ethylene glycol/inhibitor combination used in Evans Waterless Coolants, indicating a very low toxicity; and this coolant is not treated as a hazardous material, as are most water-based products.

Evans Waterless Coolant is widely used in diesel engines (which generate very high internal temperatures), by the military in both land vehicles and aircraft, and in race cars and off-road race bikes. For several months I’ve been using it in my F 650 GS and it has worked well. While the fan still comes on when the temperature gets up high enough, the heat doesn’t continue to rise. I have had no problems with overheating or losing coolant, and have become a real believer. I highly recommend you give it a try. Evans has authorized service centers if you don’t want to do this by yourself, but it’s not difficult.

Check out Evans at: www.evanscooling.com

Text by Robert Lamishaw

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