What must be adjusted first for proper magneto function?

For proper magneto function, the first adjustment that needs to be made is the magneto internal timing. This is crucial because the internal timing of a magneto determines when the spark will be produced in relation to the position of the engine's pistons. If the magneto is not timed correctly, the spark may occur either too early or too late, resulting in inefficient engine performance, potential engine damage, or hard starting.

Setting the magneto internal timing ensures that when the piston reaches the appropriate point in its cycle, the spark occurs at the right moment to ignite the fuel-air mixture. This timing is typically established during installation or maintenance and is a critical factor in achieving optimal engine operation.

Other adjustments, while important for engine performance, do not take priority over ensuring the magneto functions correctly. For example, carburetor settings may adjust the air-fuel mixture but are dependent on proper ignition timing. Similarly, throttle position and magneto-to-engine timing adjustments are relevant but can only be effectively addressed once the internal timing of the magneto is properly set.