Announcement

Collapse
No announcement yet.

fuel not flowing except on prime

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

  • fuel not flowing except on prime

    so i did a little colour tuning and checked my sync on sunday and after putting the tank and everything back on I went for a ride but it stalled out soon after and I've been having to drive around with my petcocks on prime to keep it running. I haven't had a chance to take it apart again and make sure my lines aren't kinked or whatever but any other suggestions? the vacuum line is hooked back up to carb boot 2 to my vacuum octy should be functioning.
    1979 XS1100SF 37000km
    Green Dyna Coils
    Stainless Brake Lines

    1973 CB100
    kevXS

  • #2
    If you've only got fuel flow on prime the only thing it can be is a fubar octy.
    Greg

    Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

    ― Albert Einstein

    80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

    The list changes.

    Comment


    • #3
      Make sure there is suction on the vacuum line. Make sure there is no fuel in the vacuum line. Fuel in the vacuum line indicates a ruptured diaphragm. Make sure no lines are kinked. The vacuum shutoff valve is more likely to fail leaking than fail closed.
      Marty (in Mississippi)
      XS1100SG
      XS650SK
      XS650SH
      XS650G
      XS6502F
      XS650E

      Comment


      • #4
        Originally posted by BA80 View Post
        If you've only got fuel flow on prime the only thing it can be is a fubar octy.
        Not FUBAR. If you desire, it can be fixed, and it's easy enough. Greg is probably one of those who hate it, so he'll call it FUBAR.

        I'm am one of those too mentally deficient to turn the fuel off, so I like having the vacuum valve. I'm lucky I remember to shut the engine off.
        Marty (in Mississippi)
        XS1100SG
        XS650SK
        XS650SH
        XS650G
        XS6502F
        XS650E

        Comment


        • #5
          any diagnostic tests i can do on it besides checking for fuel in the vacuum line?
          1979 XS1100SF 37000km
          Green Dyna Coils
          Stainless Brake Lines

          1973 CB100
          kevXS

          Comment


          • #6
            Originally posted by jetmechmarty View Post
            Not FUBAR. If you desire, it can be fixed, and it's easy enough. Greg is probably one of those who hate it, so he'll call it FUBAR.

            I'm am one of those too mentally deficient to turn the fuel off, so I like having the vacuum valve. I'm lucky I remember to shut the engine off.
            Ha ha ha, I took mine off the other day because I got tired of fixing it and it being in the way when I adjust the carbs. I hardly ever shut off the fuel and don't have a problem..........usually. Had a puddle in the driveway this morning though.
            Greg

            Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

            ― Albert Einstein

            80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.

            The list changes.

            Comment


            • #7
              Originally posted by kevxs View Post
              any diagnostic tests i can do on it besides checking for fuel in the vacuum line?
              Get yourself some 1/4" hose. Put one to the vacuum port on the spider valve. Disconnect the fuel lines to the carburetors. With the fuel tank all hooked up, apply suction to the vacuum shutoff and observe fuel pouring from the two hoses. If you just suck on that vacuum line, you'll be able to tell if the diaphragm is ruptured. Use a long hose, so you don't risk getting fuel in your mouth.

              Before you do that, disconnect the fuel lines from the tank and observe fuel pouring from each tap when you turn the fuel to ON. It's unlikely that both have failed, but check them anyway.
              Marty (in Mississippi)
              XS1100SG
              XS650SK
              XS650SH
              XS650G
              XS6502F
              XS650E

              Comment

              Working...
              X