The 440 in my dart likes to overheat once, and then it will stay 185 the rest of the day. It has a 180 tstat. When it gets up to 210 I can feel the thermostat housing, and it's not getting hot as it should. If I let it idle when I see it about to overheat it will hold 210-220 until the tstat opens for the first time. Once the tstat opens for the first time, everything is happy and it holds 185. I have a 440 source water pump and water pump housing. I took it off suspecting that it was a typical 440 source piece of crap, but it looks like the ports are pretty clear and large. It is a driver side exit housing. Anyone have any ideas? I have swapped tstats 4 times, same thing every time.