Many racers overlook cooling system upkeep "the technichal side"
Since my company, C&R Racing, builds a lot of racing radiators and race
season is in the dog days of summer, I felt it's time to talk about proper cooling system maintenance.
It's really not hard to keep your cooling system in proper working condition. It is
surprising that many racers, even on the professional level, overlook the basic steps to maintain
the system in their race cars.
First of all, it's very important that the proper components are being used.
Horsepower and heat walk hand in hand. Having a radiator big enough and with the
correct tube and fin design for the application is imperative. Along with the radiator, it's
equally important to use an adequate water pump that is turning the right speed, a proper working
fan, and the plumbing must be sized correctly.
Consulting with the manufacturers of these components is very important when putting
your cooling system package together.
In many race-car designs, it's difficult to fit a large enough radiator to cool the
heat generated by a high-horsepower engine. Race-car designers love very small rad inlets for
aerodynamic reasons.
Considering all the components in the system are specked correctly let's look at the
most likely causes of over-heating.
One of the biggest culprits is not getting the air out of the system. It can be very
difficult to purge all the air out of an engine. There are many places to trap air, like the
cylinder heads, and the water jackets in the block, etc.
Developing a through bleeding routine, during filling, to remove air is important.
Cracking fittings loose while filling helps.
you feel your cooling system is full, put pressure in the system by using a cooling
system pressure checker.
This will allow you to check for leaks, and while under pressure, it's a good time to
crack open fittings and bleed out any remaining air.
Keeping the cooling system clean is also an important practice.
Very good race-car mechanic and engine builder pays the utmost attention to keeping the
inside of an engine sanitary on the oil side. Many times, the same attention doesn't get paid to the
water side.
Tap water is full of minerals. When water is heated and cooled it separates these
minerals out of the water, and they form on metal surfaces. This puts an insulating barrier on the
aluminum surfaces of the radiator tubes as well as in the combustion-chamber area of the cylinder
head, the hottest spot in the engine.
I recommend using a water conditioning additive that has anti-corrosive agents.
There are many to choose from. We use a NEO product called KEEP COOL.
If your situation is right, use distilled water. This is really the very best when used
with the conditioning products.
A proper cooling fan is also vital.
Typical open-wheel cars that run on Methanol don't use fans, but the rest of the racing
world does. Electric fans from companies like Spal have come a long way.
They are getting CFM ratings that match mechanical fans and are much more sanitary to
use for racing. On the airflow side of things, having well-designed duct work to make sure the
radiator gets good air flow and volume is important. Grill screens to help keep debri out of the
core are necessary.
Using a pleated design much like shape of an air or oil filter is very effective. This allows the
debri to get trapped in pleats and air can still get in through the leading edges. Never forget
that air is what makes your radiator work. Keep the core clean.
Use low-volume air and/or water to get the dirt and rubber out of the core. Be
very careful because the air fins are delicate and will deform easily.
Following these tips will keep your race car running cool and save many headaches. Not to
mention getting your car to the end of the race.
Article by: Chris Paulsen published in "National Speed Sport News" 6/21/07
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