Gas tank

Discussion in 'Bubba's Outboards' started by nemad9, Jul 1, 2007.

  1. nemad9

    nemad9 New Member

    Messages:
    29
    State:
    wv
    ive got a 78 16 foot glastron with a mercury 850 85 hp engine it seems like it runs fine on one gas tank but as soon as i connect the other tank it starts to act up. sometimes it will die on me but start right back up it will only run full throttle for a minute or two it seems sluggish too. as soon as i put the other tank on it its fine though. ive even drained the fuel out of the problem tank and put fresh fuel in it.
     
  2. BIG GEORGE

    BIG GEORGE New Member

    Messages:
    10,362
    State:
    JOISY
    Not a pro here but it sounds like a vent problem.
     

  3. CharlieD

    CharlieD New Member

    Messages:
    69
    State:
    Lincoln,Ar
    on some of the older tanks, there is a hose that goes to the bottom of the tank with a screen on the end. The hose may be bad or the screen may be pugged up. Hope this will help
     
  4. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Either one of those suggestions could be the problem. Check the cap and see if its breathing try pumping the bulb while its doing this and also take that hose out of the tank and take that filter off of the end of it and throw it away. Install an in line filter preferable a water fuel separator.

    I know it seems like just aggravation for a tank to do that but it is putting your motor in harms way. That is a lean condition and will cause piston damage over the time and not that long of a time either.
     
  5. nemad9

    nemad9 New Member

    Messages:
    29
    State:
    wv
    ok i checked the hose that runs to the bottom of the tank and the filter looks clean. could it be the cap maybe?
     
  6. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Could be or the check valve in the bulb small hole in the diaphragm of the fuel pump. Check each and every section of the fuel system from the tank to the carbs. You can run it without the gas cap and see if that helps.
     
  7. nemad9

    nemad9 New Member

    Messages:
    29
    State:
    wv
    im thinking it has to be something with the tank because it only messes up if i use that tank it runs perfect on the other one.
     
  8. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    The pick up line that is down inside that tank could be to small to supply enough fuel to the motor.
     
  9. yotepeeler

    yotepeeler New Member

    Messages:
    71
    State:
    Illinois
    Not sure on a boat tank but do know in a diesel system of a problem that caused a lot of headaches for was found . A connection had a pin hole in it that would let it run fine until tank got down to about 3/4 full . That was on a friends dodge 3/4 ton

    Pete
     
  10. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    Pete, make a new thread for your OMC question so we dont get two different things going on this thread.
    It makes it easier for someone to search past threads for a fix to a problem.

    Thanks