Common Cooling Myths

["R. Cummings" <cumm@flash.net>]

>Folks- Thought I would share a minority opinion. I have experienced situations
>where having too much flow thru the radiator will actually cause the engine to
>run hotter. If the flow is too fast thru the core, the coolant can not
>experience sufficient heat transfer. For those doubting Thomas out there, try
>removing the thermostat completely and see what happens. I should add, I
>learned this on a 1939 Ford, so the data may be somewhat dated.
>Frank Santoro
>
This is a common myth shared by a lot of people including a number of
engineers I have met who should have known better. Having been in the heat
exchanger, engine cooling, heating and A/C engineering business for more
decades than I like to remember, I have often sat at the consoles of heat
exchanger calorimeters which measure the heat transfer performance of
radiators, oil coolers, evaporators, etc. If for example, the air side flow
and inlet temperature is held constant along with the water inlet
temperature and the water flow varied from low to high, the heat transfer in
btu/hr will ALWAYS increase with increasing flow and asymptotically approach
some maximum value.

Now I am not old enough to know anything about 1939 Fords (thank goodness!)
but my guess would be that the thermostat not only opened the path to the
radiator but also closed the bypass in the engine. Operating without a stat
allows the water to take the easiest path and circulate in the engine and
not the radiator.

Bob Cummings 87 Coupe GT