More thermostats dead horse

[graham.hilder@xxxxxxxxxxxxx (Graham Hilder)]

Are we sure it's dead yet?  I thought it was, but now not so sure.
Fred originally said (in No. 52) that 
".....any engine depending on a radiator to cool its coolant will
overheat very badly with thermostat removed."  (Because the
coolant flows too fast through the radiator to lose enough heat).

I was thinking of challenging this, going by a few old tenth-hand
cars I've bought in years past which came with either removed or
stuck-open thermostats when I acquired them (most thermostats
seem to jam in the Open position, when they fail from old age).
Until the thermostat fault was rectified these cars would never
warm up properly, let alone overheat. These would include diverse
types such as a BMC Mini or 1100, at least one Alfasud, and at
least one Alfa Romeo (a 116 Giulietta). 
Anyway I didn't feel too confident about challenging Fred, so I
held my tongue, and in no.52 or 53 Rodney said more or less what
I was thinking, i.e. gave several practical examples of
thermostat-less cars not warming up properly, and also
challenging the theory that faster-flowing engine coolant would
run hotter.
And again in no.54, Tom also said some of the things I had in
mind, noting (amongst other things) that one should not run
without a t/stat becuase that would make the engine have an
UNDER-heating problem (i.e. not an overheating problem).

So it seemed to be all wrapped up: No thermostat (or stuck-open
t/stst) = too cold engine, not an overheating engine.  But then, in
Digest no.58, Skybeaver6 wrote:
> Running a Vehicle Without a Thermostat:
> Fred Di Matteo is correct that a thermostat 'delays' coolant 
> so that it can be cooled in the radiator.  

Well I can't agree. My three or four examples of cars which ran
stone cold with open or removed thermostats won't let me agree.
(Of course 3 or 4 bad thermostats is hardly a lot of experience
compared with people such as Fred or Skybeaver, but those
results have been 100 percent consistent). 

I don't know what the theoretical explanation is, but practically
speaking, it seems that Fred's and Sybeaver's contention would
not stand to reason......  for if a stuck-open or a removed
thermostat would make an engine overheat, then surely
thermostats would be designed to CLOSE as they got hotter,  to
counter this overheating?  But they don't do that.....

And another thought on this water flow question (ref  Skybeaver:
"a  thermostat 'delays' coolant so that it can be cooled in the
radiator): it seems to me that if flow is reduced, the water hanging
around in contact with the heat-producing engine isn't being
exposed as much to the radiator dissipaton.... so surely there is
less heat being taken out of the system, simply because there is
less newly-heated water reaching the radiator where the heat can
exit the system. So, this indicates, Restricted Flow = higher
equilibrium temp, or conversley, More Flow (due to no or open
thermostat) should mean lower equilibrium  temp.

Oh well..... all I know is that my paper-reckoning fits what's
actually happened in practice in my cars....... open or missing t/stat
= cold running. 

Interesting stuff.
Regards,
Graham H,
N.Z. 

------------------------------