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Fuel pump or carb issue?-gctid807604

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    Fuel pump or carb issue?-gctid807604

    Ran the boat yesterday and had a little difficulty starting it even after reaching operating temp. After it would start it would idle and run perfectly.

    This seems to be a sudden problem as I had no problems just a couple of weeks ago using the same "start method".

    I installed a new fuel filter before my last trip so I don't suspect that to be the issue. I've been thinking about installing an electric fuel pump so maybe now is a good time to do so.

    I think I remember hearing about a leaky carb issue with these that cause a flooding scenario...obviously a new pump would not remedy that issue.

    Any thoughts?

    Hard starting even after she's reached operating temp could be a flooding issue. Maybe the needle valve has worn out and can no longer stop the flow of fuel completely or it's got some debris caught up in it. After she's warmed up (running on muffs) kill the engine and remove the flame arrestor. Take a look down the throttle bores for any signs of dripping fuel. May just need a quick carb rebuild.
    Edmonds, WA
    "THE FIX" '93 2556
    Carbureted 383 Vortec-Bravo II
    The Rebuild Of My 2556
    My Misc. Projects


      Warm engine choke should be ALL the way open .

      Are you allowing the engine to idle for a few minutes after running hard and shutting down ?

      Below is copied and pasted here i am the author.

      This is how i run a carbed motor. place in neutral ( push the button in the middle of the handle ) push the handle forward about 1/3rd... Cold i pump the throttle 2-3 times leave the throttle down 1/3 of the way and crank it. It starts i leave the throttle alone should run at about 1000-1500 rpm. Choke opens you hear the motor change, pull the throttle back neutral for another minute or 2.

      Pull the handle back. Now your able to engage forward or reverse.

      Then i slowly give throttle till i'm at say 300-3500 rpm i run 2/3 wot.

      I want to stop i slowly back off the throttle till i come to a stop put throttle in neutral and allow the motor to run at least 4-5 minutes at idle.

      Shut off motor. Say i want to start after 30 minutes i try it in neutral no pumping nothing, crank it should start.

      No start then a pump or 2 and back into neutral and crank no start then it's 1/3 down the thottle as a cold start.

      Why i just write all this cause the idle at warm up and idle before shut down
      Be good, be happy, for tomorrow is promised to no man !

      1994 2452, 5.0l, Alpha gen. 2 drive. Sold ! Sold ! Sold !

      '86 / 19' Citation cuddy, Merc. 3.0L / 140 hp 86' , stringer drive. Sold ! Sold ! Sold !

      Manalapan N.J


        All it takes is spark 'n gas 'n air. After checking for a fuel leak by peeking in the carb throat, try starting it without putting the flame arrestor back on. Clogged filters create more problems than many boaters appreciate. At the same time there is the question of temperatures of both the air and fuel. Leave the hatch open and you know that the air temp in the engine compartment is the same as that outside. The fuel temp is a different story.

        It is controlled more by the hot surfaces it is in contact with. Can you touch the carb without burning yourself when the engine is warmed up? If not, there could be some fuel evaporation taking place when you shut down. They make thicker carb/manifold gaskets to keep things cooler.

        Why this would happen today is the question. Is the engine running hotter? (cooling question) Is there a different fuel formula used at the gas dock? (did you fill up?) Could some plug wires be shorting out? (was your last run particularly bouncy?)

        FYI - I just released a book on this subject. Visit



          I have totally different motors and carbs than you but when my engines don't start like I know they should It's time for a carb clean. Always puts things back the way they should be and isn't that hard to do.
          1990 3888 Bayliner, Twin 351's