The other thing, and the real reason why hotter and cooler thermostats are
recommended for extremes of climate (well, extremes when compared to the UK)
is that there is always some cooling via the engine surfaces. Small engines
in very cold weather may never get up to temperature when cruising, which is
why people blank off the radiator in winter. They are not really blanking
off the radiator of course because the thermostat is closed anyway, what
they are doing is reducing the icy blast through the engine bay and hence
the block cooling.
When an engine is run in a relatively hot climate there is relatively less
block cooling for a given load, so more heat has to travel through the
radiator to get cooled, and heat is retained in the engine for longer,
raising the internal temperature of the engine above what is ideal. A
cooler stat helps to compensate for this reduction in block cooling.
Indeed, at one time the cooler stat was fitted as standard in order to
increase (or rather restore) oil pressure. This works by reducing the
internal temperature of the engine, so running with a cooler stat really
does allow the engine to run cooler. Likewise a hotter stat in cooler
climes helps to compensate for the *increased* block cooling and resulting
lower internal temperatures.
PaulH.
----- Original Message -----
From: Bruce Burrows <bburrows@webtv.net>
To: <mgs@autox.team.net>
Sent: Wednesday, April 19, 2000 4:39 PM
Subject: Re: (Paul) Shroud Question
>
> --WebTV-Mail-8772-525
>
> Your reply (which appears below) was a good one, Paul, and much
> appreciated. I have to say you forced my mind to work just a bit! Here
> is my best take:
...
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