I bought a pontoon with a 2006 30hp Honda outboard, and I think the fuel port must've been swapped out at some time because everything I see says this should have a rectangular securing pin on it. The Honda plug with the round pin for 4-8hp models has a smaller fuel port so that isn't it. I tried one that fit the ports but the pin wasn't long enough for the clip to catch on. Both the fuel port and securing pin are approximately the same diameter, the pin is just slightly longer than the fuel port.



