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

Announcement

Collapse
No announcement yet.

4.3 GL starving for fuel

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

  • #16
    If you have a local auto store might be able to get a vacuum/fuel pump test gauge as a loaner. Then need Merc tool or similar 91-81078 (cost $36)

    https://www.walmart.com/ip/New-Mercu...Tool/853659979

    Could also remove the fuel line between the pump and carb and take to auto store. See if they can find the fittings, rubber gas line, and tee fitting so it can be installed for testing

    The anti-siphon valve is a barbed fitting and works like this

    Click image for larger version

Name:	anti siphon valve.png
Views:	4
Size:	125.5 KB
ID:	10722269
    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


    • #17
      So I looked at all fuel lines and they seem to be in good shape, checked fuel tank vent line and there are no restrictions. I also pulled the pickup tube into tank and the screen was free and clear of debris. I also pulled the anti-siphon valve out and it looks as though it is functioning properly. I can blow though the valve and it opens but seems to need a lot of force to open it but maybe that is normal. I took it with me to the dealer to compare to a new one but the only one they had that would match my fitting was missing the ball and spring (defective from manufacturer). Talked to the service manager while there and he agreed that I've checked all the right things based on symptoms so next thing would be to test fuel pump with pressure test. Boat is now in the shop for them to figure it out. More to come in a few weeks...
      1995 Chris Craft Concept 18, 4.3 VMC7, VP outdrive

      Comment


      • #18
        If it's easy to get to the anti-siphon you can replace it with a normal fitting without the ball and see if your problem goes away. If it does, get a new valve. If no change, put your current anti-siphon valve back in.

        Comment


        • #19
          Shop called today and said they have fixed the problem. It was the anti-siphon valve after all. They also replaced the fuel pickup tube going into the tank since there was some air leaking in somewhere. Possible crack in tube? I'll find out more when I pick it up and take it out for an extended run. Lesson learned, since this boat is 24 years old, the fuel system has likely never been touched except for fuel line replacement from tank to fuel pump which I did several years ago. Should have replaced all of that when I bought the boat as preventative maintenance.
          1995 Chris Craft Concept 18, 4.3 VMC7, VP outdrive

          Comment


          • #20
            had the same problem with the anti-siphon on my boat when we bought it a long time ago. Boat would start, idle, rev in neutral but would not plane out the boat.
            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
              UPDATE... took the boat out yesterday after picking up from shop and all was well; at least I thought so Ran fine cruising for about 30 minutes then it happened again. Died like it wasn't getting fuel. Got it cranked after a few tries and ran slow in a "no wake zone" for about 5 minutes and died again. Did this again another time. So I figured it was troubleshooting time, I had all day. I checked the carb by disconnecting the throttle linkage while engine was off and advancing the throttle manually at the carb. Fuel sprayed into carb like it should. While I was there, I looked at spark plug wires at distributor and didn't like the way they were routed with a little strain on wires so I disconnected one at a time to reroute and give some slack(just anal about stuff like that). Cranked back up and ran about 7 MPH with just enough speed to keep load on engine bow up to see how she ran and potentially pick up any bad fuel or water in tank while doing so. Ran like this for about 40 minutes, then picked up speed to about 22 MPH and 3k RPM's for another 30 minutes or so then picked up speed to about 30 MPH and 3.5k RPM's for another 2 hours or so. I killed the engine 2-3 times during this last several hours and let set several minutes to see if heat buildup while stopped would affect anything. I was never able to get the kill scenario repeat itself again. Total run time yesterday was about 3.5 hours mostly at cruising speed. I'm still scratching my head on this one. A little bad fuel or spark plug wire breaking down? Also talked to mechanic after all of this and he was puzzled as well and said sounds like a coil or other ignition component breaking down when it heats up but that it would be hard to diagnose without catching it in the act. sorry for the long post but maybe someone else can chime in.
              1995 Chris Craft Concept 18, 4.3 VMC7, VP outdrive

              Comment


              • #22
                Cap or rotor??

                Comment


                • #23
                  Talked to mechanic about that too. He seemed to think no since engine's not missing and runs good except for intermittent shutdowns.
                  1995 Chris Craft Concept 18, 4.3 VMC7, VP outdrive

                  Comment


                  • #24
                    If it appeared to get better after fiddling with the spark plug wires and the cap, I would replace the cap, rotor, and spark plug wires. If something is intermittent between the coil and center of the cap, that could explain the symptoms.
                    Rich

                    1995 Chris Craft 21 Concept (OMC 50FAPHUE)

                    Comment


                    • #25
                      I'm thinking electrical. It doesn't dies slow it just dies right?

                      If its electrical it can be many things
                      ignition switch
                      loosing ground
                      bad connection
                      kill switch
                      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


                      • #26
                        Originally posted by AllDodge View Post
                        I'm thinking electrical. It doesn't dies slow it just dies right?

                        If its electrical it can be many things
                        ignition switch
                        loosing ground
                        bad connection
                        kill switch
                        Alldodge, yes it just dies like I had ripped the kill switch loose, not a slow death.

                        1995 Chris Craft Concept 18, 4.3 VMC7, VP outdrive

                        Comment


                        • #27
                          Sign up today
                          That could be hard to find. Bring along a volt meter and when it dies see if there is power to the coil without turning engine off (leave it on)
                          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

                          Working...
                          X