Ignition Coil: Description and Operation

PURPOSE
Coils are constructed using the principle of mutual induction to step up low (battery) voltage to high (ignition) voltage capable of firing the spark plugs.

LOCATION
On a bracket beneath extension manifold.

OPERATION
When current flows through the outer, primary winding, a magnetic field is created. When the primary current is interrupted by the igniter, the magnetic field collapses suddenly. The change in magnetic field induces high voltage in the secondary windings. Ignition wires then direct voltage to the spark plugs. The ratio of the number of turns in the primary winding to the number of turns in the secondary winding determines voltage multiplication.

CONSTRUCTION
Coils consist of two windings of wire, primary and secondary, around a laminated iron core. The trailing side uses a separate coil for each plug. The leading side uses one coil for both plugs.