At 07:30 AM 2/23/97 -0800, TeriAnn Wakeman wrote:
>At 8:32 PM 2/22/97 -0700, Jane Burdekin wrote:
>>Jay, 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.
>>
>>Jane
>>'67 GT6
>
>
>A TR3 has a radiator bipass. This allows water to circulate within the
>engine while the thermostat is closed. This eliminates hot spots in the
>head that can lead to head cracks. The thermostat has a skirt that acts as
>a valve for the radiator bipass. When the thermostat opens, the skirt
>closes off the bipass. If you have the wrong thermostat or no thermostat
>in place close to half of the coolent will bipass the radiator and stay in
>the engine (guessed quantity based upon size of bipass hose and radiator
>rods).
>
>If you have no thermostat, the coolent 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 termerature. An engine that runs
>too cool emits more SMOG, is not as effecent as a warm engine, may collect
>water vapour in the oil and reduce engine life.
>
>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.
>
>
>TeriAnn Wakeman "Large format photographers look
>Santa Cruz California at the world upside down and
>twakeman@scruznet.com backwards"
>
>
>We have had this thread several times the past couple of years. Do to the
turn it has taken I felt I must jump in . The paramount reason for
overheating in a TR2,3,4 is a non stock thermostat or no thermostat.
TeriAnn"s description of it is exactly correct. However I must disagree with
her statement "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 coolant flow , the coolent just may not have enough contact
time to transfer much heat." This statement conveys the mistaken idea that
by restricting the flow the engine will run cooler. What actually happens
is, if the flow is slowed in passing through the radiator, the flow through
the engine is slowed, the longer the water stays in the engine, the hotter
it gets.
Sam Haynes 59 TR3 Original Owner
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