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Model T Secondary Ignition Basics

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  • Model T Secondary Ignition Basics

    Buzz box 101!!

    Original Thread

    The basic Model T ignition system has four buzz coils. Each coil is timed to fire a specific spark plug at the correct time. The four buzz coils are in a box and when the key is turned on the brass plate at the bottom of the box is energized. The brass plate contacts the bottom of each coil, so they are all powered whenever the key is on, and each will fire when the circuit through them goes to ground. There are four wires coming out of the side of the coil box which go to a timer on the front of the engine. These wires go to ground one at a time as determined by the timer, and when one of the wires goes to ground the associated buzz box fires the related spark plug.

  • #2
    3 ~ Tudor's
    Henry Ford said
    "It's all nuts and bolts"


    Mitch's Auto Service ctr

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