Re: Vintage Single OMC Line Fuel Tank Home › Forum › Ask A Member › Vintage Single OMC Line Fuel Tank › Re: Vintage Single OMC Line Fuel Tank chinewalkerUS Member - 1 Year (includes $3 online payment fee)Replies: 459Topics: 15 April 20, 2018 at 8:56 pm #74393 As I noted in previous post, one pin lets fuel out, the other lets air in.