Buy Yamaha Outboard Parts

Announcement

Collapse
No announcement yet.

250 0x66 fuel problem

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 250 0x66 fuel problem

    I have 2000 250 ox66 when I was out last on the boat the moter just shut down Iwas able to resart but did again. I let it sit for awhile and re started and it seems to be fine ? any ideas I checked primer it was fine . when I took the boat out for the winter I drained gas from the bottom of the racor and let sit and its clear no water , but Idid notice when priming bulb I had gas coming out the exhaust any ideas? bad fuel pumps?

  • #2
    sounds like a fuel pump if there is excess fuel.

    Comment


    • #3
      Sounds more like a problem with the float in your carbs. Pressing the primer bulb forces fuel past the leaking float valve filling the carb throat and then leaking into the cylinders and out the exhaust.
      When running the engine probbly gets flooded and runs rough or dies out.
      MHO

      Comment


      • #4
        thanks for the reply, but no carbs its fuel injected. low pressure pumps maybe? any other ideas? thanks

        Comment


        • #5
          luckily the only issue ive had with my pair was 1 o2 sensor, so i have no low pressure pump experience. if the fuel pump diaphragm is bad, the case pressure pulls fuel thru it, non spent fuel. if you dont get the answers you want, repost your question specifically to boats.net, as he wont respond after other have.good luck with it and please post your fix !

          Comment


          • #6
            jb,
            Gonna show my ignorance here because I don't have much experience with the fuel injected motors. Correct me if I am wrong.
            You have in the fuel system a primer bulb, a local filter, low pressure pump, and a high pressure pump or fuel injector. When the primer bulb is squeezed, I can understand fuel getting all the way thru to the injector pump, but that is as far as it should go - right? Sounds like a bad check valve/s in the injector pump to me.
            What do you think?
            Ken K [img]smile.gif[/img]

            Comment


            • #7
              honestly ive had my motors for about 3 yrs now,ox66 200`s , and after i posted i went to the parts list to ensure they had exterior fuel pumps,similar to most all the older motors, and they do, as i wasnt sure and have never seen them.so i assume the pump feeds the pressure tank.now whats inside the aluminum pressure tank i have no idea only that they and their components are expensive as H*(( !
              so as for a direct answer to his question im not sure as ive not had that issue with these motors, but i have had that same issue with my older pro-v.maybe boats.net could shed some light [img]smile.gif[/img] and does he have a name?

              Comment


              • #8
                Cobia
                It's probably the fuel pump diaphragms(low pressure pump) the diaphragms will rupture and fuel will go into crankcase. Take fuel pumps off and check the back diaphragms if they have a clear diaphragm then replace them with 6E5-24411-00-00 rubber diaphragm.The plastic is for alcohol blended fuel and works well for that but are easily ruptured. As for the aluminum tank it can overflow it is a fuel vapor separator tank(VST) and it has a float in like carbs, if overflow it will overflow gas through vent hoses on top of tank into air silencer cover on throttle body's. The VST allows air bubbles to escape from fuel and cools fuel before the electric fuel pump(med pressure) that is inside VST tank pumps fuel at 35-50psi to fuel injectors. The HPDI models also has a high pressure pump that is belt driven on back of engine that pressurize fuel to injectors to 700psi and the 2006 models 1000psi(2 high pressure pumps). The EFI's are doing well but clean fuel is the trick use the best fuel water separator filters and change on a regular basis
                Regards
                Boats.net
                Yamaha Outboard Parts

                Comment


                • #9
                  boats.net,
                  Are we talking about an outboard motor here, or the Space Shuttle!!! [img]smile.gif[/img]
                  Geez, what a complex system - but thanks for the explanation - I just hope I never have to work on one!
                  Ken K [img]smile.gif[/img]

                  Comment


                  • #10
                    thanks for all the input. I'll check the low pressure pumps this weekend . I live on long island so we have alot of problems with the ethanal in the gas.thanks

                    Comment

                    Working...
                    X