Operation

Does Evans coolant require periodic maintenance?

No periodic addition of supplemental coolant additives is required, nor should any ever be added. Evans recommends inspecting the cooling system at least once a year to ensure that no contamination of the coolant has occurred.

If I have a leak or other event where I need to top off or refill my coolant and Evans is not immediately available, what can I safely add to the cooling system?

With Evans waterless coolant, the likelihood of coolant loss and the need for topping up are greatly reduced. In the event that there is significant coolant loss from the system during operation and no Evans waterless coolant is available to fill the system, water or water-based coolant may be used. However, repairs should be made as soon as possible, and the system should be drained, purged and re-filled with Evans waterless coolant.

What if I am using Evans waterless coolant and I get a leak?

Leaks should be repaired. Stop-leak type products are not intended to be permanent repairs, but they may be used as a temporary measure. Carefully follow the instructions on the stop leak product label. Overuse may clog radiator and heater core passageways.

What effect will mixing Evans coolant with water or water-based coolant have on my cooling system?

In the short term, no performance issues should result from mixing a small amount of conventional coolant or straight water with Evans waterless coolant. However, the high boiling point and corrosion protection of Evans waterless coolant will be reduced, and the coolant should be replaced as soon as possible.

How do Evans waterless coolants control engine metal temperatures as compared to water-based coolants under stressed conditions?

Water-based coolant boils at a temperature only slightly higher than the operating temperature of the coolant. The boiling point of water-based coolant is somewhat above the boiling point of water for the pressure of the system. Localized boiling releases water vapor that can only condense into coolant that is colder than the boiling point of water. Any vapor that doesn’t condense occupies a volume that displaces liquid coolant. Water vapor is a very poor conductor of heat. Hot engine metal, insulated by water vapor, becomes an engine “hot spot” that can cause pre ignition and detonation. In contrast, the boiling point of Evans waterless coolant is much higher than the bulk coolant temperature and any locally generated vapor condenses immediately into the surrounding bulk coolant. There is no persistent vapor to insulate between hot metal and the liquid coolant. Liquid coolant is in contact with all of the coolant jacket at all times, providing a path of excellent heat transfer away from the hot metal.

How does Evans coolant prevent after-boil?

After-boil occurs in an automotive engine after engine shutdown when the heat in the system cannot be rejected to the air because the coolant is no longer being circulated to the radiator. A coolant near its boiling point will not be able to absorb additional heat without boiling and being forced out through the pressure cap. Conversely, the huge separation between the operating temperature and the boiling point of Evans waterless coolant enables the coolant to act as a heat sink into which heat from hot metal parts of the system can be readily dissipated. Boiling is avoided and there is no build-up of pressure to force coolant out of the system. Stresses on cooling system components are avoided because metal temperatures are kept under control. Learn more about how Evans waterless coolants prevent overheating.

How does Evans coolant prevent water pump cavitation?

Evans waterless coolant inhibits vapor development in the pump over a broad range of temperatures. With Evans waterless coolant, the suction side of the coolant pump is never at a low enough pressure to flash vaporize the coolant. So, the pump never gets vapor-bound and has the ability to pump coolant over broad range of temperatures. No vapor bubbles are formed to collapse against the metal and cause cavitation erosion damage to the pump. Learn more about how Evans waterless coolants prevent erosion.

Will Evans coolant lower the operating temperature of my engine?

The effect of Evans waterless coolant on cooling system temperatures will depend on the engine and cooling system configuration, as well as driving conditions. Vehicles running under normal operating conditions should show either no change or a slight increase in temperature. In high horsepower applications, the temperature effect of running Evans waterless coolant will depend on the engine and cooling system components.

Is Evans advocating operating engines at higher temperatures?

Not really. With Evans waterless coolant, operating temperatures may be modestly higher than those of water-based coolant, depending on driving conditions and whether the vehicle is stock or configured as high-performance. When the engine is stressed, the coolant absorbs more heat and temperatures rise. This is not a concern when using Evans waterless coolant. The combination of the high boiling point of Evans waterless coolant and a correctly-sized cooling system means that an increase in temperature can be accommodated without cooling system failure.

If I increase my engine horsepower and want additional cooling capacity, what suggestions do you have for radiators?

In general, Evans recommends single-pass radiators as they have less flow resistance than multi-pass radiators.  The following are minimum radiator core suggestions:

  • 300HP or less without AC........................4 rows: ½” tube copper/brass
  • 300HP to 400HP with AC........................2 rows: 1” tube aluminum
  • 400HP to 600HP.......................................2 rows: 1.25” tube, aluminum
  • 600HP and above.....................................3 rows: 1” tube aluminum
                                                          OR     2 rows: 1.5” tube aluminum