jmoore If you can look in the radiator neck wouldn;t that mean the coolant isn't hot --so thermostat is closed --no flow right?? If thermostat was out you would then see flow from a cold start till you had to put the cap on. My big radiator 6400 runs 185 degrees mostly full time year round,even in the hot-soak of a parade is original and clean with a 235 insert upgrade engine.
