Ignition Coil
The ignition coil is a sort of miniature transfor-
mer and, as such, has an iron core around which
two coils are wound - primary and secondary
windings mentioned above. The two are so close
to each other that a sudden change in the
magnetic flux produced by "primary current"
flowing in primary winding (in a less number of
coil turns) induces a very large electromotive
force (voltage) in secondary winding (in a
greater number of coil turns). These live parts
are housed in a tight, insulator case topped by
the cap. Note that the cap has three terminals:
one high-tension terminal and two low-tension
terminals.
High-tension
terminal
Fig. 8-5
Spark Plugs
Each new machine shipped from the factory is
fitted with standard plugs.
Standard type
NGK
Nippon Denso
8-4
Primary terminal
Case
Primary winding
Secondary winding
II
insulator
Cold type
Copper core
Center electrode
Fig. 8-6
Insulator