[Excaliber]

The second small line to the top of the radiator is a good call! It allows air to bleed out of the top of radiator back to the overflow tank. Instead of a bleed line, my radiator has a manual vent valve in that position. IF you DON'T bleed the air from there it WILL get trapped in the upper portion of the radiator. This WILL result in an overheating condition, no biggie if you bleed it yourself and one less hose to worry about rupturing. If I was 'racing' I wouldn't use the 3/8ths line, I'd bleed manually.