Ignition System: Description and Operation

PURPOSE
The ignition system provides spark control during all modes of engine operation.

OPERATION
When ignition is switched "ON," it charges primary coil windings. When engine is running, the ignition control module induces a spark by grounding the coil primary circuit negative side.

When the ignition module grounds the primary circuit, inductive charge built up in the secondary circuit sends spark from the coil to the distributor. The rotor and cap then sends spark to each plug.

Ignition timing must be variable due to the wide variation in engine speed and load under normal operating conditions. When accelerating or climbing hills, the engine load can be high and the amount of spark advance required is not necessarily as much as it would be on level ground at an equivalent engine speed. Ignition spark advance is achieved by two separate systems: mechanical advance weights and a vacuum diaphragm unit.

CONSTRUCTION
The engine uses an integrated distributor mounted system with vacuum advance.

Primary Ignition
The primary ignition components include coil primary circuit, ignition control module, and ignition switch.

Secondary Ignition
The secondary ignition components include spark plugs and wires, distributor cap, rotor, and coil secondary circuit.