TeriAnn Wakeman wrote:
> At 8:32 PM 2/22/97 -0700, Jane Burdekin wrote:
> >I used to run with out the thermostat in the summer. It helped keep
> >it a bit cooler. Otherwise I use a summer therm. usually as I have a
> >problem with running too hot. I think it would be similar with a TR3.
> A TR3 has a radiator bypass. ... If you have the wrong thermostat
> or no thermostat in place close to half of the coolant will bypass
> the radiator and stay in the engine (guessed quantity based upon
> size of bypass hose and radiator rods).
The above is a *very* important reason for always having a thermostat
in a TR3, as the following:
> If you have no thermostat, the coolant takes longer to get up to
> temperature. On cool days where the engine is not working hard, the engine
> may never come up to optimum operating temperature. An engine that runs
> too cool emits more SMOG, is not as efficient as a warm engine, may collect
> water vapour in the oil and reduce engine life.
However, is the next piece of information is correct?
> On hot days or when the engine is working hard the car may overheat without
> a thermostat. The water pump pumps water through the radiator at a rate
> corresponding to the engine speed. The longer the water is in contact with
> the radiator surface, the more heat can be transfered. Without the
> restriction of the thermostat slowing down the coolent flow the coolent
> just may not have enough contact time to transfer much heat.
Are there any thermodynamics instructors out there? I had thought that
it *IS* important to run with a thermostat for the above
reasons, but running the water through the cooling system
more quickly *does* cause the engine to run more cool.
For, even though each individual molecule of water spends less
time in the engine (and radiator), transferring less heat
on each trip, each individual molecule also makes more
trips through the system. The resultant effect is that the
engine and radiator are kept at more uniform temperatures
(difference in entry/exit temperature of the water is not
as high) and the radiator is thus able to extract more heat
from the engine.
Then again, I'm no thermodynamics expert, either...
--ken
'74 TR6, Daily Driver for 6 months each year...
--
Kenneth B. Streeter | EMAIL: streeter@sanders.com
Sanders, PTP2-A001 |
PO Box 868 | Voice: (603) 885-9604
Nashua, NH 03061 | Fax: (603) 885-0631
|