The ignition distributor plays a pivotal role in the ignition system. Its basic functions start with triggering the firing of the ignition coil, controlling timing advance, and routing or distributing the coil’s high voltage output to each spark plugs.
In the case of older applications with breaker point ignition systems, the contact points are made to turn the ignition coil’s primary voltage on and off. This are mounted on a flexible plate in the distributor unit or housing. Cam lobes mounted on the distributor shaft turn against a plastic block on the breaker points to open and close the points. However in modern applications made with electronic ignition systems, the distributor has a magnetic pickup or Hall Effect switch instead of the old points
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