Low temperature thermostat

[Starter986]

Originally Posted by JFP in PA

OK, that's easy, your wrong. The thermostat in the engine functions just like the thermostat in your house; it throttles coolant flow to maintain proximity to its rated temperature. If your cooling system did not have the excess heat transfer capacity in the radiators to shed sufficient heat, it would never cool back down running after getting stuck in traffic; but that is not what happens, it does cool back down until the thermostat takes over flow control again. The internet "old wives tale" about thermostats not controlling steady state temperatures has been needlessly confusing people for millennia. One of the easiest ways to prove my conjecture is to totally leave out the thermostat; if your idea was correct, the engine would still get up to 210-220 F; but that is not what happens. Instead, it struggles to get above 120-140 F under the same operating conditions because coolant is circulating too fast and the radiators are pulling out the heat faster than the engine can produce it.

Thermostats in your engine serve a vital function, just like the one on the wall in your home, without them things would get rather uncomfortable.

If I have a LTT in, and it fully is open at ~160 degrees... water will circulate sooner... and will sooner reach operating temperature ~210 degrees. Assuming no city driving... the temperature should remain at ~210 degrees.

If I have in a stock thermostat... and it fully is open at ~210 degrees... water will circulate later... and will later reach operating temperature ~210 degrees. Assuming no city driving... the temperature should remain at ~210 degrees.

By later I mean like around 5 minutes.

Under what conditions would the/either thermostat, while the car is running/driven, open and close according to the temperature? If the car, with either thermo, is at ~210 degrees... the thermo will remain in the open position. Highly it is unlikely, while driving, that the coolant temperature will hit the ~160 degree mark.

Is that correct? Believe me... I want it to "click".

Would it be prudent to install a coolant temperature guage (aftermarket)? If affirmative, which one would YOU recommend?

Thank you, JFP.