Since the 1930s, hot rodders and performance car enthusiasts have relied primarily on engine coolants made from a mix of ethylene glycol, water, and corrosion inhibitors. While these water-based coolants have done an admirable job of cooling, history shows they can be prone to overheating, boil-over, and after-boil conditions at high operating temperatures.
In other words, traditional water-based coolants are susceptible to traditional cooling system problems.
According to Evans Cooling, there’s a better, more effective way to cool your engine — and it doesn’t include water. The company has developed a line of waterless coolants that consist of a propriety, water-free base fluid that doesn’t have the physical and chemical limitations of water.
Evans Cooling Waterless Solution
By eliminating water from its coolant formula, Evans Cooling says its waterless coolant offers three main advantages over traditional water-based coolant:
What’s worse than that plume of steam coming from your hood? How about seeing the coolant actually boil over and overflow from your radiator? If you’ve ever owned an old car with a non-pressurized cooling system, you may have enjoyed the experience once or twice.
Evans Cooling says it has eliminated the overheating problem altogether by removing water from its coolant formula. While water begins to boil at 212 degrees F — very close to the operating temperature of an engine — Evans uses a propriety liquid that it claims has a boiling point of over 375 degrees F.
Here’s why that’s important:
When water reaches its relatively low boiling point, it begins to vaporize. Since vapor is about 97 percent less effective than liquid at conducting heat, it reduces the coolant’s overall ability to do its job. This vapor is most likely to occur around the hottest parts of the cylinder head — right where the cooling is needed most. What’s more, localized vapor pockets can build up around these hot spots and actually create a barrier between the hot surface and the coolant, preventing the necessary heat transfer. This makes the metal even hotter, worsens the overheating, and can potentially lead to cylinder head warping and detonation.
This overheating and thermal stress on metal parts can lead to:
- Reduced combustion efficiency (loss of power)
- Erosion caused by pitting on the cylinder heads, pump, and other areas
- Cavitation when combined with pressure drops in the water pump
- Leaks due to cylinder head surface warping
The higher boiling point of Evans waterless coolant ensures the coolant remains a liquid at all times, maintaining effective cooling. And since the 375-degree boiling point is considerably higher than the operating temperature of most engines, any localized vapor is absorbed back into nearby coolant, which remains way below its boiling point.
Oh yeah — and since there’s no water in the coolant, you never have to worry about boil-over or after-boil, either.
When coolant vaporizes, it creates added pressure within the cooling system. This puts stress on hoses, connections, and other components within the cooling system. Because Evans Cooling Waterless Coolant is much less likely to vaporize, it reduces this stress and can eliminate the expense of replacing ruptured hoses or damaged components.
It’s simple — water causes corrosion.
Although corrosion inhibitors have evolved over the years, current water-based antifreeze formulations regularly fail to prevent cavitation, oxidation, and galvanic action that can damage pumps, radiators, and other metal components. Corrosion build-up, inhibitor drop-out, and lime-scale precipitation significantly reduce heat transfer efficiency and accelerate overheating.
Evans waterless coolants prevent corrosion in a cooling system.
How to Convert to Waterless Coolant
Once you’ve decided the switch to waterless coolant is the right choice, there are some very specific steps you must follow for a seamless transition. First and foremost, all existing water-based coolant must be drained from the system. The water content of your Evans Cooling coolant should not exceed more than 3 percent to be effective, so the company recommends the use of its Prep Fluid to absorb any residual water or coolant. Also, the system should undergo a chemical flush if any contamination is observed.
Below is Evans Cooling’s basic process for converting to waterless coolant. Unlike traditional coolants, which should be changed periodically, Evans Cooling Waterless Coolant lasts the life of the engine and requires no topping as long as the cooling system is leak-free. That means once the conversion is made, you’re good to go.
Drain the System
- Once the engine has cooled, remove the pressure cap and open all drain valves and plugs, along with bleeder or petcock vents, if present.
- Drain all parts of the system, including radiator, coolant reservoir, engine block, and heater. Draining the system only from the bottom of the radiator removes less than half of the system capacity. You should use high-volume/low pressure air to gently blow out various parts of the system. If accessible, blow out the heater circuit, blowing only in the direction from the hot coolant source (generally, the cylinder head) toward the coolant return (generally, the inlet to the coolant pump). Ensure that the heater control valve is open before applying the air.
- Block drains are frequently inaccessible, ineffective, or non-existent, and considerable amounts of coolant can remain in the block. Removal of the thermostat provides an opening to the engine where high volume air can be blown through the head and block, pushing old coolant past the coolant pump and out through the bottom radiator hose or radiator drain. For V6 and V8 engines with inaccessible block drains or no block drains, refer to www.evanscoolant.com for special procedures to achieve a proper conversion.
- Engines having an “inlet side” thermostat and a good block drain does not require removal of the thermostat. With the block drain open, air blown toward the engine through the top radiator hose will purge the residual coolant in the block.
- Empty the overflow bottle completely, if the vehicle is equipped with one. If the system has a pressurized expansion tank, blow air into it to make sure it is empty.
Purge the System
- Close all drain valves, plugs, and vents and reconnect circuits. If the engine is equipped with a coolant filter (heavy duty systems), replace the filter with one that does not introduce coolant additives.
- Fill the system with Prep Fluid to flush parts of the cooling system suspected of harboring residual coolant or water. Vent as needed to ensure a complete fill.
- Replace the pressure cap and run the engine with the heater on (at the highest temperature) for 10 minutes after reaching operating temperature (thermostat open).
- Repeat the sequence given in step 1 to drain the used Prep Fluid.
Refill the System
- Close all drain valves, plugs and vents, and reconnect all circuits.
- Fill the system completely with the appropriate Evans Cooling Waterless Coolant, and start engine. Add coolant as needed to keep system full. If system is equipped with a vented overflow bottle, leave it empty for now.
- Replace the pressure cap and run engine with the heater on (at the highest temperature) for 10 minutes after reaching operating temperature (thermostat open). Shut off the engine and allow the system to cool.
Test the Coolant
- Draw a sample of well-circulated coolant from the radiator or pressurized overflow reservoir. Check the water content using a refractometer or test strips once the coolant reaches room temperature. Be careful to minimize exposure of the coolant to air during testing.
- If the above procedure has been rigorously followed, the water content of the coolant should be within specification (below 3 percent). If the water content exceeds 3 percent, run the system again to operating temperature and allow sufficient time for the thermostat to open and fluid to circulate through the radiator. Repeat sampling and water content test. If the water content still exceeds the limit, you can see the remediation procedure here.
- If the water content is 3 percent or less, the equipment is ready for use. Ensure the overflow bottle or expansion tank is filled to the “cold” mark with Evans Waterless Coolant. Place Evans warning stickers in strategic locations (radiator cap, radiator shroud, overflow bottle, expansion tank) to warn against adding water or water-based coolant to the system.
- Upon cool-down and for a few days after, you may need to add small amounts of Evans Waterless Coolant. Whether the system has a pressurized expansion tank or an overflow bottle, the coolant level should be at the cold line when the engine is cold.