I am about to go get my car from my general mechanic, who has told me that the overheating I have experienced has to do with a crack in the radiator. So far, that makes sense, except for this...

I saw that the heat was high on the guage. It would cool down if I used the car heater core, or at least cool down a bit.

This is why I am asking the question... The car has a wet spot on the cowl under the radiator, but no great leak. It was only down a 1/2 gallon. The mechanic said he ran it two hours yesterday, and an hour today, and it did not heat up.

I have never heard of a radiator leak that overheated the car, before it lost fluid.

I would have thought that if a bubble were in front of a temperature sensor, it would give a bad reading, but how does that explain the inability for the mechanic to make the car heat up.

I would love some hands on advice. I have no problem replacing the radiator if that is the problem, but this seems like a reach. I am wondering if it was a simple stuck thermostat or something...
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