Ignition Contact Breaker Plate

The ignition contact breaker plate is a component of the ignition system in an internal combustion engine. It is responsible for controlling the timing of the spark that ignites the air-fuel mixture in the engine's cylinders.

The contact breaker plate consists of a metal plate that is mounted on a pivot and connected to the engine's camshaft. It has a set of contact points, typically made of tungsten or platinum, which open and close as the plate rotates. These contact points are connected to the ignition coil and distributor.

As the engine rotates, the camshaft causes the contact breaker plate to move, opening and closing the contact points. When the points are closed, an electrical current flows through the primary winding of the ignition coil. When the points open, the current is interrupted, causing a high voltage spark to be generated in the secondary winding of the coil. This spark is then sent to the appropriate spark plug to ignite the air-fuel mixture in the cylinder.

The timing of the spark is crucial for the engine's performance and efficiency. The contact breaker plate can be adjusted to ensure that the spark occurs at the correct moment in the engine's cycle. This adjustment is typically done using a timing light, which allows the user to accurately set the ignition timing.

In modern vehicles, electronic ignition systems have largely replaced contact breaker plates. However, in older vehicles or classic cars, contact breaker plates are still used. They require regular maintenance and occasional replacement of the contact points to ensure proper ignition timing and reliable engine performance.