Originally Posted by VincentJ

Lupe, the fuel line that I like to use is made by Sullivan and it's called ProFlex. Tygon fuel line hardens and requires yearly replacement, especially the clunk line in the tank. Switching over to ProFlex has eliminated the need to replace clunk lines that aren't flexible. The down side is that it is pricey! If you chose to use it be aware that it comes in two sizes so make sure to purchase the larger line when using on gas engines.