What is inside a small engine electronic ignition module?
The advantage of these systems is that there is no maintenance as there are no points to wear out or gum up. Timing is fixed by the relationship of the flywheel magnet and sensor. There are also no adjustments except to set the magneto coil pole piece to flywheel air gap. Replacement modules are available for many small engines to take the place of their original point type ignition system. These can be designed in several different ways but all must emulate the behavior of the point type ignition replacing just the magneto coil/pole piece assembly and without requiring alterations to the flywheel. • One design uses the flywheel magnet passing the coil pole pieces to induce a moderate voltage – a few hundred volts – and store this in a capacitor. A sensor coil then triggers a solid state switch which dumps the charge in this capacitor into a high voltage transformer (ignition coil) to produce the spark.
The advantage of these systems is that there is no maintenance as there are no points to wear out or gum up. Timing is fixed by the relationship of the flywheel magnet and sensor. There are also no adjustments except to set the magneto coil pole piece to flywheel air gap. Replacement modules are available for many small engines to take the place of their original point type ignition system. These can be designed in several different ways but all must emulate the behavior of the point type ignition replacing just the magneto coil/pole piece assembly and without requiring alterations to the flywheel. • One design uses the flywheel magnet passing the coil pole pieces to induce a moderate voltage – a few hundred volts – and store this in a capacitor. A sensor coil then triggers a solid state switch which dumps the charge in this capacitor into a high voltage transformer (ignition coil) to produce the spark. • Another possible approach is to provide a coil in which current builds up until t
