extreme conditions for long periods of time, replace the
plastic parts with metal ones.
Hot spots. When you get vapor in the cyl-inder-head passages, the vapor pushes the
liquid away from the metal in that spot, which
raises the metal’s temperature by hundreds of
degrees. This is what causes detonation, warped heads
and blown head gaskets. These hot spots don’t develop
with waterless coolant, because the waterless liquid will
always be in contact with the metal to cool it down.
Conversion. To ensure you get the full
benefits of waterless coolant, the cooling
system must be completely drained or
have a maximum of 3-percent water. The
best way to ensure this is to remove the drain bolt, then
pull the hose off at the pump. Now, blow compressed air
in at the top of the radiator. Put the hose and drain bolt
back in (finger-tight) and pour one or two cups of either
the waterless coolant or prep fluid (the prep fluid is the
cheaper route) in the radiator. Then, drain and blow it out
again before the final assembly and coolant fill. ❏
Waterless coolant. Let’s state the obvious:
waterless coolant is different from regular coolant because there is no water in it. Waterless
coolant is made up of the same basic glycols
as regular coolant but operates much differently without
the water. There are a few waterless coolant companies on
the market, but only one markets worldwide and is highly
involved in the motocross industry. That company is Evans
waterless coolant. They let us in on some secrets, good and
bad, on the effects of waterless coolant.
Temperature. The boiling point of water-
less coolant is 375 degrees Fahrenheit and it
freezes at - 40 degrees Fahrenheit. Instead of
expanding when frozen, like water does, with-
out the water, the coolant actually decreases in volume.
Stability. Waterless coolant additives do not
fall out of solution as with regular coolant.
Stable additives are added to the waterless
coolant so the coolant never goes bad, whether
it is used or still sitting in the container, so it never has to
Vapor pressure. Waterless coolant doesn’t
build vapor pressure in the system. There is
moderate pressure build-up from a 7-percent
fluid expansion, so if you open the radiator cap
when the coolant is hot, it may spill out a few tablespoons,
but it doesn’t have the vapor pressure that can blow up in
your face like regular coolant. It must be said that if there
is residual water still in the system (over 3 to 5 percent),
vapor pressure will build.
Mixing. If you have waterless coolant in your
system and it is low and you didn’t bring extra
waterless coolant to the track, don’t worry.
You can add water or regular coolant to the
system with no issues. With water added, it will behave
just like regular coolant and lose the waterless-coolant
ASTM. The ASTM, the organization that sets
the bar in over 12,000 technical standards
worldwide, has a waterless-coolant standard.
So before making a purchase of waterless coolant, make sure it meets the ASTM standards to ensure you
are investing in a high-performance product.
Corrosion. Many waterless coolants, includ-
ing Evans’ old formula, would corrode with an
addition of only 3-percent water. A waterless
coolant that meets the ASTM standards can
have up to 10-percent water and still retain its anti-corro-
sion properties. Evans Coolant will still protect with up to
60 percent water. It can’t, however, retain its lifetime use
with water added and will go bad within a few years.
High temperatures. In long, hard races
where the terrain is muddy, it is possible that
mud can get packed into the radiators and
restrict airflow and engine cooling. Regular
coolant is going to boil out. If you don’t let the engine
cool down or refill it, you will damage the engine. With
waterless coolant, the engine will continue to run fine with
restricted airflow, although it is possible that the plastic
parts in the cooling system, such as the pump impeller or
fittings holding the radiator hoses together, can melt. If
these parts are plastic on your machine and you ride in
YOU NEED TO KNOW ABOUT WATERLESS COOLANT