Welcome Guest - Sign Up today
Welcome Guest - Sign Up today

Announcement

Collapse
No announcement yet.

Gas leaking out through exhaust

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

  • #16
    Originally posted by QBhoy View Post
    Hi
    i have the mercury equivalent of this engine. Mine will throw fuel out the exhausts until it warms up. They over fuel when cold usually. It also gets worse when the diz cap is on its way to being done.
    This is leaking even at normal op temp. Not sure if the cap, wires, or plugs are bad, but the boat only has 70 hours. Not sure if they are possible candidates, but I'm considering changing them all out. I really don't think that is going to fix my issue. I'm guessing its a stuck injector, but I'm open to anything that might help.
    2004 Regal 2000 5.0L GXi

    Comment


    • #17
      you have a fuel injected engine. there is a fuel cooler, specifically the module that the fuel pumps sit in is water cooled. it is a few stamped pieces and a few machined pieces that are brazed / soldered together. there are two locations that if there is a seam leak, will leak high pressure fuel into the raw water stream.

      pressure test the raw water side with air, 15-20 psi should hold forever.
      Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

      1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

      Past Boats
      1970 Wooster Hellion - Merc 9.8
      2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
      1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

      What’s behind you doesn’t matter.Enzo Ferrari

      Comment


      • #18
        To find out if the pump is leaking into the cooling water, disconnect both water lines from the pump and plug or connect them together. Start the motor and see if fuel start coming out of the ports
        94 Formula 27PC Custom 509MPI MEFI3 , B3 XR
        95 Rinker 232 w/ 7.4L Carb 0F425011 B1 0F486471
        07 Seadoo GTX
        Merc Adults Only VP Adults Only
        G-Dad always said "First Liar doesn't stand a chance"

        Comment


        • #19
          Thank you Scott and AllDodge. I will check. I'm thinking you guys are right since this fuel pump has been my downfall. Thanks again!
          2004 Regal 2000 5.0L GXi

          Comment


          • #20
            Originally posted by QBhoy View Post
            Hi
            i have the mercury equivalent of this engine. Mine will throw fuel out the exhausts until it warms up. They over fuel when cold usually. It also gets worse when the diz cap is on its way to being done.
            That just does not seem right....even my ancient 4.3 with the 4bbl Quadrajet doesn't do that with the slow-to-open up auto choke!
            1988 Four Winns 200 Horizon
            4.3 OMC Cobra

            98 Jeep Grand Cherokee 4.0 Selectrac
            07 Jeep Grand Cherokee Limited 5.7 Quadradrive II

            "While air doesn't freeze....rust never sleeps"

            Comment


            • #21
              Originally posted by AllDodge View Post
              To find out if the pump is leaking into the cooling water, disconnect both water lines from the pump and plug or connect them together. Start the motor and see if fuel start coming out of the ports
              AllDodge, which two hoses? There are three water lines connected to the fuel pump. Two into the top of the fuel pump, and one at the bottom. I'm guessing two flow in and one flows out? Please let me know and I'll try that today.
              2004 Regal 2000 5.0L GXi

              Comment


              • #22
                I'm only seeing 2, but you could plug all 3, or Y all 3 together. The supply thru the pump is minimal to effect anything on the motor. If its leaking it shouldn't take long to see, maybe 30 seconds if that
                94 Formula 27PC Custom 509MPI MEFI3 , B3 XR
                95 Rinker 232 w/ 7.4L Carb 0F425011 B1 0F486471
                07 Seadoo GTX
                Merc Adults Only VP Adults Only
                G-Dad always said "First Liar doesn't stand a chance"

                Comment


                • #23
                  Originally posted by AllDodge View Post
                  I'm only seeing 2, but you could plug all 3, or Y all 3 together. The supply thru the pump is minimal to effect anything on the motor. If its leaking it shouldn't take long to see, maybe 30 seconds if that
                  I pulled the lower water hose (the one that connects to the thermostat housing), and without even running the engine, a bunch of water mixed with gas poured out of the hose. Is that water entering the pump or draining from the pump? Is it safe to assume that my fuel pump is pumping gas through a bad seal inside the pump and the gas is getting into the cooling water? Is it possible that water is also getting into the fuel lines? I pulled this fuel pump apart on my last trip because it was clogged. I put it back together after cleaning it out and had to re-use all the seals/o-rings. I'm guessing it needs to be replaced or rebuilt. Thanks again!!
                  2004 Regal 2000 5.0L GXi

                  Comment


                  • #24
                    Pulling the hose and finding gas and fuel mix, the Scott identified the issue and its inside the pump. I doubt you need the pump rebuilt but do need some new O rings, and not just any, needs ones that are not effected by E10 gas.

                    My guess is you could take the pump down to NAPA and they would be able to find some
                    94 Formula 27PC Custom 509MPI MEFI3 , B3 XR
                    95 Rinker 232 w/ 7.4L Carb 0F425011 B1 0F486471
                    07 Seadoo GTX
                    Merc Adults Only VP Adults Only
                    G-Dad always said "First Liar doesn't stand a chance"

                    Comment


                    • #25
                      Originally posted by AllDodge View Post
                      Pulling the hose and finding gas and fuel mix, the Scott identified the issue and its inside the pump. I doubt you need the pump rebuilt but do need some new O rings, and not just any, needs ones that are not effected by E10 gas.

                      My guess is you could take the pump down to NAPA and they would be able to find some
                      I'll give it a try. Thanks!
                      2004 Regal 2000 5.0L GXi

                      Comment


                      • #26
                        pull the fuel cooler

                        remove the pumps

                        inspect the solder/braze joints

                        repair as needed

                        re-install fuel pumps with PTFE or viton seals

                        go boating.
                        Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                        1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                        Past Boats
                        1970 Wooster Hellion - Merc 9.8
                        2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                        1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                        What’s behind you doesn’t matter.Enzo Ferrari

                        Comment


                        • #27
                          Originally posted by Scott Danforth View Post
                          pull the fuel cooler

                          remove the pumps

                          inspect the solder/braze joints

                          repair as needed

                          re-install fuel pumps with PTFE or viton seals

                          go boating.
                          I pulled the pump apart and several o-rings were destroyed. I am ordering a set from man cave mechanic, but I'll probably see if I can get some locally too. I plan to clean it up as much as possible and get it back up and running. Thanks for your help in diagnosing the problem!
                          2004 Regal 2000 5.0L GXi

                          Comment


                          • #28
                            I try to keep a few multi-size o-ring kits on hand.

                            for sizes not in the standard kit, there is always McMaster Carr.
                            Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                            1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                            Past Boats
                            1970 Wooster Hellion - Merc 9.8
                            2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                            1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                            What’s behind you doesn’t matter.Enzo Ferrari

                            Comment


                            • #29
                              Originally posted by Lou C View Post

                              That just does not seem right....even my ancient 4.3 with the 4bbl Quadrajet doesn't do that with the slow-to-open up auto choke!
                              I suppose it’s a very different engine from the carb. My old carbs used to black smoke on warm up...the mpi throws raw fuel into the water. I think it’s further worsened with mine because of the cam in mine.

                              Comment


                              • #30
                                Sign up today
                                Originally posted by Scott Danforth View Post
                                you have a fuel injected engine. there is a fuel cooler, specifically the module that the fuel pumps sit in is water cooled. it is a few stamped pieces and a few machined pieces that are brazed / soldered together. there are two locations that if there is a seam leak, will leak high pressure fuel into the raw water stream.

                                pressure test the raw water side with air, 15-20 psi should hold forever.
                                May be wrong but I don’t think they are all fuel cooled systems. Don’t think mine is. Or it certainly doesn’t have the cool fuel at least.

                                Comment

                                Working...
                                X