[rss396]

My 61 has a very similar heating problem. Over the years I have been told the faster you go the hotter she gets the problem is the radiator is plugged or to small of a radiator. I inspected mine and sure enough the core is plugged. The fan and shroud has little to do with cooling at highway speed because there is plenty of air flow at highway speed. IMO you need to have the radiator rodded out.