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 garry-in-michiganLifetime MemberReplies: 3583Topics: 31 April 20, 2018 at 5:47 am #74361 The expanding bulb pulls the gas from the tank, squeezing it pushes it to the motor . . . 😆