Ignition Systems

Small Gasoline Engines:

Operation, Repair and

Maintenance

Ignition Systems:

The first phase of small gasoline theory

of operation.

Group of component parts which

delivers the spark to the spark plug at

the precise moment to fire the

compressed air-fuel mixture.

IGNITION SYSTEM

MAGNETO POWERED (MAGNETO IN FLYWHEEL)

BATTERY POWERED (12 VDC STORAGE BATTERY)

With Breaker- Points

Solid-State

Without Breaker-

Points

Solid-State

Without Breaker-

Points

With Breaker- Points

Magneto-Ignition Systems:

Induced electrical current originates from a rotating magnet.

There are two types of Ignition Systems:

– With Breaker-points

– With/out Breaker-points

Magneto-Ignition System with

Breaker-points

Contains 2 Circuits:

Primary:

– Breaker-points

– Condenser

Secondary:

– Spark Plug

– Spark Plug Wire

Magneto-Ignition Systems:

An understanding of each part of the

magneto-ignition system is required to

comprehend how the system delivers a

spark to the combustion chamber at eth

precise moment.

It will be most helpful to become familiar

with the general component parts.

Magneto-Ignition Systems:

Flywheel Magnet: Produces electrical energy

Magneto-Ignition Systems:

Armature: “Pick Up” of a magnetic field from a moving magnet, and assists the coil in “Building Up” a stronger magnetic field.

Two types:

Magneto-Ignition System

Solid-State Ignition System

Magneto-Ignition Systems:

Coil: Transformer that converts low

voltage to high voltage.

Magneto-Ignition Systems:

Breaker-points: Two contact surfaces

that open and close to control the flow

of electricity.

Magneto-Ignition Systems:

Condenser: A device that stores a

surge of electrical current for late

discharge.

Magneto-Ignition Systems:

Spark Plug

Spark gap

Center Electrode

Shell

Ground Electrode

Reach

Insulator

Terminal

Ignition Timing:

Is an aspect of small

gasoline operation

that is very crucial.

Is the point in the

crankshaft revolution

circle at which the

spark plug is fired.

A Complete Magneto System:

THE END