Boat motor question

Discussion in 'General Conversation' started by bigmike, Jul 25, 2006.

  1. bigmike

    bigmike New Member

    Messages:
    288
    State:
    Kankakee,Illinois
    I have a 10hp evinrude w/ the factory metal dome shaped evinrude gas tank. When I hooked my motor to my buddies regular plastic gas tank it would not hold a prime and it does with mine. After playing around we opened the gas cap on the plastic tank an ran it on my motor and it worked fine. Could the different gas tanks have a different pressure in them or what would cause this with the primer balb for one tank to work and the other to have to have the gas cap off to work????? One of my buddies is having a problem with his primer bulb holding a prime and we were trying to narrow down the problem. Thanx
     
  2. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    When you pull a liquid out of a closed container, you create a vacume. They have to be vented.

    Your metal tank has a vented cap that allows air pressure to equalize. Not all metal tanks do, most if not all plastic tanks have a screw in the cap to vent to outside air pressure so no vacume is created in the tank, allowing an easy flow of gas to the engine.

    8th grade science class, you guys must've been out sick that day:lol:
     

  3. AwShucks

    AwShucks New Member

    Messages:
    4,532
    State:
    Guthrie, Oklaho
    Your fuel hose has rubber "o" rings at the ends which connect to the motor and to the tank. Usually, a loss of prime is because these "o" rings no longer function properly. Replace them, they are cheap, and see if it solves the problems.
     
  4. jaybird78

    jaybird78 New Member

    Messages:
    69
    State:
    Illinois
    Are you sure your budies tank was plastic. I think it was a metal tank for a mercury. :0a20: :big_smile:
     
  5. bigmike

    bigmike New Member

    Messages:
    288
    State:
    Kankakee,Illinois
    Bill told me it was plastic. I would hope he knows his own tank