Originally Posted by topside
I'll add:
I always put a new thermostat in water, boil it, and note opening temp with a meat thermometer, before I install it.
If the OP has an air compressor, blow air from behind & through the radiator fins & see how much junk blows out.
Look for traces of coolant (stains, if not wetness) all around anything that carries or contains coolant.


The Dodge FSM I have says .003 minimum open at the temp rating. It's well worth fussing over after I had a stat fail this test years beck.