THERMOSTAT - How Important

[cadayjerry]

most of the second hand cars that i had has no thermostat. In my tamaraw fx, one mechanic remove the thermostat for reason of a better water circulation from the radiator. When i had my engine overhauled by a mechanic whose specialty is engine overhauling, he insist that we should re-install the thermostat. the reason is for a longer life of the engine.

I was convince that thermostat is important so i install one in my lancer. i observe however that the engine seems to be too hot and the temperature guage reach the half mark in just 1 kilometer distance. the good thing is that, the temperature guage does not go higher than the half mark. before the thermostat was installed, the temperature guage never reaches the half mark. the peak was at the 1/4 mark.

To test at what point the thermostat opens, i submerged the new thermostat of the lancer and FX into a pot of water and heat it in a stove. i discover that the thermostat opens only when the water starts boiling.

QUESTION - 1. Is the temperature when the water starts boiling is 82 degrees as it is indicated in the thermostat?
2. Is the temperature of the water at boiling point is normal to the engine?
3. How important is the thermostat since i also observe that my gas mileage increased when i installed a thermostat?

[vinj]

IMO, it's an old wives tale that the thermostat isnt needed in the Phils.

Without the thermostat the water/coolant runs freely; to the point that your engine may be running too cool then what is intended (meaning it is running out of the optimal temp range). I noticed also that your location is in Baguio city so that would mean your temp there is generally cooler (more meaning for the thermostat then).

Just to clarify: your got better fuel consumption when you had the thermostat installed? When the engine isnt running at the optimal temp range (i.e. cold morning starts) thats when it also consumes more fuel.

Isnt the boiling point of water 100c?

[CVT]

"Thermostats" are installed, in order to make sure that the engine is running at the optimum temperature, and consequently, optimum efficiency,- regulated by the car's cooling system. As for your observation that mileage is better on a car without a "thermostat", where the temperature gauge is only at "1/4", that is also my experience in my previous cars, which is on the contrary.

Some say that they're installed for countries where the weather is usually cold to bring up the engine temperature fast when you start the car.

[cadayjerry]

I strictly monitor my gas mileage which is about 7.2 km/liter on the average. the temperature guage plays at 1/10 and most of the time even lower. the guage only reach the 1/4 mark when i drive over one hour on uphill road but drops to the 1/10 mark on flat roads. the pointer never moves in the morning even when warmed up for 10 minutes unless you drive for about 1 kilometer before it starts moving just a little. But when the thermostat was installed, it reaches the 1/2 mark in just 3 minutes of warming up. i recorded an average of 8.5 km/liter lately with the thermostat.

VINJ, if the temperature is 100 degrees when the water starts boiling, then the thermostat which has a mark of 82 degrees must be defective. the two thermostat (for FX & for Lancer) that i tested repeatedly is a genuine replacement parts (new) and both only opens when the water starts boiling.

Is the temperature when the water start boiling the same as when the water is already boiling as in evaporating? is there a thermostats that opens at a temperature lower than 82 degrees?

[vinj]

In that case the thermostat does it's job in getting the engine to operating temp right away so it runs more efficiently.

It is unlikely the thermostat is defective; one possibility is it could be calibrated to take into consideration that the mixture being used is a water and coolant mix rather than pure water (coolant has a higher boiling point) so when it reaches a certain temp or pressure, it is assumed that the mixture going through it isnt boiling yet (i'm just guessing on this here. ).

[OTEP]

Thermostats are not really that exact re: opening and closing times.

But I'd rather have one that opens a bit early or a bit late than not have one at all.

[cadayjerry]

thanks to everybody!

i found similar thread. at last, alam ko na how important is the thermostat.
http://tsikot.yehey.com/forums/showthread.php?t=10440
http://tsikot.yehey.com/forums/showthread.php?t=3785
http://tsikot.yehey.com/forums/showthread.php?t=13280

[edl100]

I think it the thermostat is important. Running the engine too cold destroys the engine.

Like most expensive euro cars with Catalytic Converters, Mercedes for example, runs better with a hotter engine. these cars run at almost 95 to 98 degrees on the average.

On Opels too, if you run it too cool, palyado ang takbo and malakas sa Gas.

Nakakatakot lang talaga since it runs too near the 100 degrees mark which is an overheat!!

[XTO]

diesel engine tends to run smoothly when it reaches normal operating temp. thermostat is very important. without thermostat delays the required operating temp of the engine.

[acenie]

diesel engine tends to run smoothly when it reaches normal operating temp. thermostat is very important. without thermostat delays the required operating temp of the engine.

saan ba ang location ang thermostat(control the water flow) ng L300 4D56 Engine.