fuel leaking from holley carb after shutdown

Discussion in 'Fuel and Air Systems' started by duster360, Jun 30, 2018.

  1. duster360

    duster360 Well-Known Member

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    What would cause fuel to leak from the carb down into the intake after the engine is shutoff?
     
  2. fishmens67

    fishmens67 Well-Known Member

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    could be the float level is too high, that'd be the 1st thing I'd check
     
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    • duster360

      duster360 Well-Known Member

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      Fuel level is about half way up the sight glass.
       
    • rklein383

      rklein383 Well-Known Member

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      Too high, should just barely dribble out of the hole, if sight glass removed.
       
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      • krazykuda

        krazykuda FABO Gold Member FABO Gold Member Technical Editor

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      • mullinax95

        mullinax95 Well-Known Member

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        Heat soak
         
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        • 68 HEMI GTS

          68 HEMI GTS Well-Known Member

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          Blown/leaking power valve. Wrong/bad gaskets.
           
        • duster360

          duster360 Well-Known Member

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          Had this happen with 3 different carbs. The first one was a new vacuum secondary holley. Then I rebuilt and installed a holley DP. New one now is an AED DP. All three of them had this same issue.
           
          Last edited: Jul 1, 2018
        • duster360

          duster360 Well-Known Member

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          This is what I am thinking.
           
        • barbee6043

          barbee6043 barbee 6043

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          Holley
           
        • fishmens67

          fishmens67 Well-Known Member

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          hum, what am I missing here. too high, should be at the bottom
           
        • duster360

          duster360 Well-Known Member

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          It has the large sight glasses. AED says that is where they prefer the fuel level. When they told me this, I was discussing things in general with them when I bought the carb, not about the issue I am having. May not be working for my application though. Maybe I should try the insulator and lower the level a little.
           
          Last edited: Jul 1, 2018
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          • duster360

            duster360 Well-Known Member

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            I have decided to go with one of these but not sure which. My intake is Edelbrock Airgap. Should I get the 4 hole and modify it into a dual plane or just get the single hole.
            3106794.jpg 3926707.jpg
             
          • oldkimmer

            oldkimmer Well-Known Member

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            Open will be fine. U may have too much fuel pressure. Kim
             
          • duster360

            duster360 Well-Known Member

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            I am currently using a Carter mechanical pump regulated to 6 1/2 psi I got from Mancini. I have also tried the 5 psi stock pump from the local parts store with the same results.
             
          • inertia

            inertia Well-Known Member

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            Isn't that just a metal shield ?
            The spacer most use is of insulating material to help stop transfer of heat.
            Black phenol, or wood has been used ,
            Google it,
             
          • oldkimmer

            oldkimmer Well-Known Member

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            Yes,it’s a shield the keeps heat off the fuel bowls. They have been around since the 70s. They do help a lot. The thick gasket/spacer is prolly better. Kim
             
          • mderoy340

            mderoy340 Well-Known Member

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            I run an open plate I made and added a shield up front to keep the heat from the upper radiator hose off the primary bowl. I also run a 1" 4 hole phenolic spacer.

            000_0303.JPG
             
          • inertia

            inertia Well-Known Member

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            I like them both too Kim, when there's room. cheers
             
          • duster360

            duster360 Well-Known Member

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            Actually it is 2 pieces of aluminum with a polymer in between to dissapate the heat.
             
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            • jimb

              jimb Member

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              Make sure float is good seen them fill up with gas.