Motor runs fine, but boat barely moves?

Discussion in 'Boat Modification Journal' started by daniel-delarosa, Aug 31, 2008.

  1. daniel-delarosa

    daniel-delarosa New Member

    Messages:
    392
    State:
    seminole, oklahoma
    I was at the lake doing a test run with the '85 Glasstream that I got the day before. The motor starts easily, and Idles fine. I tried to go forward, and it dont seem like the boat is moving as fast as it is supposed to. It feels like it is barely creeping along. It has a 50hp Mariner and the boat is only 15 foot long. I dont know a thing about how to work on outboards. Any Ideas?
     
  2. DANZIG

    DANZIG New Member

    Messages:
    6,672
    State:
    West Virginia
    The first thing that comes to mind is weight. How is she sitting in the water? Could the floatation be saturated? The pics kinda had the look like she sat uncovered for a while. Can you get her to a set of scales and check it out against what that model should weigh?

    Check the simple stuff first, plugs and such.
    Or, Hole in the fuel line(bulb) sucking air?, fuel pump diaphragm? I have had those problems before. Would run fine till I dropped the hammer, then go mushy.
     

  3. fish

    fish Active Member

    Messages:
    1,573
    State:
    ChattanoogaTenn
    Sounds like it may be a spun prop.
     
  4. biga

    biga Well-Known Member

    Messages:
    2,111
    State:
    evansville
    i 2nd fishs idea...
     
  5. jtrew

    jtrew New Member

    Messages:
    4,404
    State:
    Little Rock, AR
    Sounds like a real good possibility. Put the boat in forward, give it some gas, and watch to see if the prop is pushing a lot of water. If not, it's a spun prop.
     
  6. LEROYDOZOIS

    LEROYDOZOIS New Member

    Messages:
    1,542
    State:
    Arizona

    Sounds like a really good possibility!!!!!!!!!!!!:smile2::roll_eyes::smile2:
     
  7. daniel-delarosa

    daniel-delarosa New Member

    Messages:
    392
    State:
    seminole, oklahoma
    Whats a spun prop? One thing I did do today was change the oil in the lower unit. No metal chunks, just black oil.
     
  8. Poppa

    Poppa New Member

    Messages:
    1,233
    State:
    Pinson, Al
    If the boat stays docked in the water it could have algae on the bottom.
    a dirty bottom can kill your speed.
     
  9. fish

    fish Active Member

    Messages:
    1,573
    State:
    ChattanoogaTenn
    A spun prop is kinda like a slipping transmission, your motor revs up but don't take off like it should. When you pour the coal to it, your motor should move a lot of water and if it isn't then it could have a spun prop. Check out this thread http://www.catfish1.com/forums/archive/index.php/t-54250.html
     
  10. daniel-delarosa

    daniel-delarosa New Member

    Messages:
    392
    State:
    seminole, oklahoma
    I read that post and tried what it said. I put the lever in the forward position and I could turn the prop to the right(clockwise), by hand freely. It sounded kinda like a clicking. The nut turned with the prop also. I tried turning it the opposite way(counter clockwise) and it turned the engine. In netural it would turn freely in either direction. I tried the motor on my 'toon and it turned the engine over either way with the boat in netural?