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- Solex 34 Pict 3 Carburetor Tuning -

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  • Things to do before tuning
    • Check or adjust the Valves
    • Check the Points (if you have them)
    • Check and set the Timing

  • Inspect the choke
    • Warm up the engine
    • Remove the air cleaner (either paper or oil bath)
    • Choke butterfly should be vertical
      • If its not vertical, keep warming the engine
      • If it still doesn't go vertical, adjust the choke


  • Now on to the actual tuning of the carb
    • Tools needed for adjustments
      • Large sloted screwdriver
      • Small sloted screwdriver
      • Tachometer - either in the car or an inductive pickup

    • Main parts that need adjustments
      • Fast idle screw - long thin screw that is on the throttle arm
      • Bypass screw - large screw (rounded head) on the drivers side
      • Volume screw - small recessed screw (flat head) on the drivers side next to the Bypass screw
    Solex 34 Pict 3 Carburetor
    • Adjust the Fast Idle screw so that it just touches the bottom of the stepped cam (below the first step) and turn it 1/4 of a turn in - do not go farther or the adjustments will not be correct
    • Set the Bypass screw to about 2 1/2 turns out (gently bottom the screw out and then back it out)
    • Set the Volume screw out exactly 2 1/2 turns (gently bottom the screw out and then back it out)
    • Start the car and adjust the Bypass screw until the engine idles at about 850 RPM
    • Adjust the Volume screw to fastest idle (turn screw no more than 1/2 turn in either direction)
    • Adjust the Volume screw until the RPM drop about 25 RPM (slight audible slow)
    • Readjust the Bypass screw to set the idle back to 850 RPM

  • Drive your well adjusted carbureted engine around!