'73 Duster 440, not sure the size of the aluminum radiator.
Wasn't even 70 degrees outside and it overheated after driving about 30 miles. Popped the hood and the lid to the overflow tank was missing (popped off somewhere I assume) and the coolant was boiling like crazy. I let it cool down then continued on my way. Another 25 miles and I stopped to cool down again Then after my business out of town was complete, I drove 60 miles back home, without a problem. Temperature stayed cool, coolant wasn't boiling out of the overflow anymore. Once it was cool to the touch, I still had some coolant in the overflow, so I didn't lose much when it boiled over.
I don't know if some gunk got stuck in the line somewhere or what, but I think I need to flush it all just to be sure. Any other thoughts?
