Re: Minor point on thermostats

[Jay Mackro <jmackro@xxxxxxxxxxxxx>]

At 12:57 PM 9/24/98 -0400, Scott Fisher wrote:

>Subject: Thermostats and Temperature Control Systems
>Graham Hilder mentions that he's owned several cars that *did* run
>colder when he removed the thermostat...

Keep in mind that when you say "run colder" what you really are
saying is: "that one area in the engine / manifold where the
temperature sensor is located was recording a lower temperature".
This is different from" "the entire engine, including the critical
areas around the valves, ran cooler".  

My understanding of the problem with removing the thermostat is
that while you are reducing the resistance to coolant flow, and
thereby increasing the rate of flow, you are also decreasing the 
coolant pressure upstream of the thermostat, since it isn't
getting restricted by the thermostat. At a lower pressure, the 
coolant will boil at a lower temperature, and since a gas conducts 
heat a whole lot less effectively than a liquid, a lot of BTU's
are getting left behind.  So, sure, your temperature gauge may
suggest that everything is OK, but your valves could still be
getting cooked.

Jay Mackro

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