Accelerator Pump Plunger question - Holley 4160 465 cfm

Discussion in 'Fuel and Air Systems' started by Stroked68Dart, Oct 26, 2018.

  1. Stroked68Dart

    Stroked68Dart 402 Crate Motor in a 68

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    Hi guys!
    I have been searching the forums for an answer to the below question. I did not find an answer but boy I learned a lot about Holley carbs :)

    My question:
    I have a Holley 465 cfm carb. When I fully depress the gas pedal it completely actuates the throttle linkage to a complete full stop on the carb but the lever that goes to the accelerator pump only pushes or travels far enough to plunge the accelerator pump 1/2 way down or up I guess would be more correct. With the lever 1/2 plunged I can literally take my finger and push the accelerator pump arm another 1/2 an inch which gives the rest of the squirt.

    I have checked to make sure the screw with the spring on it that pushes on accelerator pump actuator arm is correctly adjusted (basically it touches it or is almost touching it).

    If it was depressing the accelerator pump perhaps 90% I wouldn't worry about it but it is only traveling 1/2 as far as is needed.

    So... any advice or thoughts?

    Thanks!
     
  2. mderoy340

    mderoy340 Well-Known Member

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    Get a spring and hold the throttle wide open. Adjust the pump screw to get full pump travel minus .015. You don;t want the pump to bottom out.
     
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    • 69FBCuda

      69FBCuda Life in the Fast Lane

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      How far the pump lever travels doesn't matter, you could actually damage the diaphragm if you Push it too far. The squirt is based on the lever ratio. Barely touching while lightly pressing down on the lever, that would be the starting travel point, is how you want it set. Is the stock pump cam still on it?
       
      Last edited: Oct 26, 2018