[Healeys] thermostat discussion - Part 1

[BJ8 Healeys]

Kees, I understand how cooling systems work, but your reply doesn't address
the point that "going to a 160 thermostat will allow the coolant to flow too
fast through the radiator to cool it."  That is what I was responding to.  
 
Your arguments about the thermostat seem to be based on modern automotive
cooling systems that have the capability overcool the engine, and thereby
(with the influence of the thermostat) regulate the coolant temperature to a
more or less constant stabilized value.  Thus, the temp gauge on a modern
car seems unaffected by ambient conditions -- heat of the day, level of
traffic, quantity of traffic lights, use of air conditioner, etc.
My experience with my Healey is that the temperature of the coolant (as
displayed on the gauge) depends very closely on ambient conditions.  It has
been that way in the 25 years I've owned the car, even after a complete
engine rebuild and a new radiator.
I have a 180-deg. thermostat.  I can leave home pre-dawn on a long cruise
and the gauge will hold steady at 180 - 190 until the sun comes up.  The
gauge will show a rise to somewhere above 190 until the heat of the day,
when on a really hot day it can approach 200 at cruise.  During our return
across the California desert last summer (ambient temps 115 - 118), the car
ran at 212 on the gauge.  I can drop the temperatures on my gauge 10 degrees
temporarily just by coasting down a long hill.  With a 180 (or any other)
thermostat, once the coolant temperature goes above that due to ambient
conditions, the thermostat has no further ability to affect the coolant
temperature.
 
Part 2 to follow.
 
Steve Byers
HBJ8L/36666
BJ8 Registry
Havelock, NC  USA
 
-----Original Message-----
From: Oudesluys [mailto:coudesluijs at chello.nl]
Sent: Thursday, July 16, 2009 2:11 AM
To: BJ8 Healeys
Cc: 'Healey List'
Subject: Re: [Healeys] thermostat discussion
 
Steve,
The total flow of coolant is more or less the same at a given engine speed.
At all times all the coolant is passed through the engine.When the engine is
cold most coolant will be circulated through the by-pass and only a trickle
through the radiator....