oldfart1941

I purchased a 67 camaro with a ls2 instal. with over 6,000 miles on it it has ran super until friday nite when I was stopped in construction traffic and it super overheated and shut down. After letting it cool I got it restarted and managed to get it home. Today I got the car over to my electical wizard friend. He discovered the ground on the fan connection under rad had came loose,he found this after a electical check on the relay. before fixing the break he did a polarity check and told me the fan was pushing and should be pulling as it is mounted on the inside.He reversed the wires and everything seems fine, we did a one hr. purge on the rad to get any trapped air out and with the diagostic gauge hooked up to the computer plug we watched as the temp would rise to 201 and the fan would cut on ,go down to 190 and cut off. We let the car run for an hr. no overheating whatsoever.Problem seems solved??.My ? is why did it run so fine for over a yr.with the fan pushing???