> Date: Wed, 22 Sep 93 11:13:36 PDT
> From: megatest!bldg2fs1!sfisher@uu2.psi.com (Scott Fisher)
> To: british-cars@autox.team.net
> Subject: Light and Heat (was Re: Problem Solving)
> Cc: bldg2fs1!sfisher@hoosier.cs.utah.edu
>
>
> Let me repeat: the reason your car runs hotter with the thermostat OUT
> than with it IN is most likely because the thermostat is there as a
> flow-direction device, moving coolant through passages in the head as
> well as through the radiator. For Jim's Mini in particular, I can
I'm loathe to prolong this discussion but I have a somewhat related
question. Years ago I had a Dodge Aspen with a slant 6. At one point
after several years of ownership I noticed that the temperature gauge
never seemed to get up to the normal level no matter how warm the
weather was or how long the engine had been running. Even turning on
the A/C didn't seem to have an effect. My initial reaction to this was
who cares: too hot is bad; too cool is okay. But then I got to
thinking about those engineers in Detroit with slide rules and computers
calculating the tolerances between all those moving pieces inside my
engine. There must have been a reason for designing the cooling system
so the engine ran at a temperature higher than what mine seemed to. So
I decided to look into the matter. Maybe the thicker core radiator I'd
installed a couple of years early just made the car run cooler. But
that didn't seem right. What was the point of a thermostat if it
couldn't control the temperature. Besides, I didn't recall the car
running any cooler when I'd first put it in.
Maybe the gauge was off. That seemed more likely and besides, it was
easy to check. I got the engine stabilized at its operating temperature
and removed the radiator cap. The cap didn't seem that hot. I even
stuck a finger in for a tentative check. The coolant didn't seem near
hot enough to me. Next came the real test. I stuck in a candy
thermometer. The reading was about 20 degrees less than what the manual
said was normal. So my gauge wasn't lying (actually the only marks on
the gauge were C, N and H). Well, maybe the top of the radiator was
supposed to be 20 degrees cooler. But the coolant just didn't seem as
hot to me as I'd recalled it being in the past.
Since there was only one thing to try that was relatively easy and
cheap, I bought a new thermostat and pull the water pump. Hmm, the old
thermostat was badly corroded and frozen in the fully open position. I
put the new one in, reinstalled the water pump and voila, normal running
temperature from then on.
So, is this the secret to making your race car run cooler?
Roland
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