The common points on an ignition switch include: Lock, Off (not on all vehicles); Accessories, On and Start. The key can only be removed from the 'Lock' position.
The contact breaker is a mechanically operated electrical switch in the primary ignition circuit. The contacts open and close automatically with engine rotation.
The distributor in a contact breaker system distributes the high-tension voltage surges to the spark plugs in the correct sequence and at the correct instant in time in the engine cycle.
Spark plugs deliver the spark that initiates combustion in an engine cylinder. They are identified by thread size or diameter, the reach or length of the thread, and by their heat range.
The main spark plug components are a threaded metal case with a ceramic insulating covering, a sparking tip with an adjustable spark gap, center and side electrodes and a terminal to connect the plug to the ignition system.
