How could a car without a thermostat overheat? Lets assume the rad waterpump etc are in good shape. Isn't the purpose of a thermostat to allow the water to come UP in temperature before opening and allowing it to cool in the rad? So if there was no thermostat present, logically that would mean the water is circulating from the get go thus taking a lot longer to get into operating temperature.
That is my understanding of it.
However its a good idea to have one as engines operate best within a certain temp range and the thermostat controls that.
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