Will your engine survive when a sudden loss of radiator coolant occurs?

We’ve all been there or seen it happen at some time.  Driving down the road maybe on a vacation trip and a radiator or heater hose suddenly bursts and you’ve run out of radiator coolant.  Often times you won’t even notice the problem until a warning lights up on the instrument panel.

In my case, my smart car lost coolant and the engine overheated but never gave me an over temperature indication on the instrument cluster. Only when the coolant temperature sensor failed due to excessive heat in the cylinder head, did I get any indication that something was wrong with the engine. Unfortunately by then it was too late and severe damage occurred to the engine.

Now I would think that the coolant temperature sensor would indicated a problem if the coolant operating temperature was too low or too high but the sensor has to make contact with the coolant to get an accurate measurement. In this case however, the coolant stops making contact with the sensor so I’m assuming that some intermediate dry air temperature was probably measured so no trouble was seen by the sensor.

I realize that quite a few of you reading this already have a scan gauge II plugged into your OBDII port and can read coolant temperature but isn’t that temperature coming from the same coolant temperature sensor that I’m currently having issues with?

I know that this is a very common single point failure on any car with a coolant system. As these coolant systems age, I expect a whole lot more engine failures in the future. Other manufactures provide at least a low coolant indicator.  Others may have a secondary sensor monitoring the head temperature.  I would think that Mercedes/Mitsubishi engineering would have a solution that would give some indication of a problem long before engine failure. 

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So, tell us more.  What exactly happened?

Diane Elmore said:

Yipee!  I got my Smart Car back yesterday and I couldn't be happier.  I even got the guys at the dealership to show me several important things I needed to know, bought an extra bottle of engine coolant and some windshield wiper fluid, and I am ready to go.I have 3 events in March I am planning to attend and I am sure on the very first one everyone who knows what happened to my car, will converge on me to make sure I know how to check this, and check that.  I will also be told several "extra" things to buy.

Once again, thank you Smart USA and Mercedes Benz.  I am forever grateful.   Diane

Wouldn't it be nice if Smart would just come clean and let us know what trashed Diane's engine, so the rest of us might know what to listen and look for on our little problem children?  I can't accept they don't know, EXACTLY, what blew this engine.  They're hiding something, again.

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