Distributor Cap and Rotor

Distributor Cap and Rotor for Classic Cars

Distributor Cap and Rotor for Classic Cars

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The cap which forms the top of the distributor is made of an insulating material.

In addition to covering the top of the distributor, it is formed to serve as the terminals or connections for the high tension wiring.

The centrally located terminal receives the high voltage from the coil, while those equally spaced around the outside of the cap connect the distributor to the spark plugs.

Located directly below the center terminal is the rotor which rotates with the breaker cam.

So when the high voltage from the coil secondary is received at the center terminal, it is passed to the rotor.

The rotor is turning in time with the engine, so when it rotates under each of the outer terminals, it passes the high voltage surges from the coil.

These surges are directed first to one spark plug and then to another according to the engine firing order.

The rotor used in a distributor rotates on the end of the distributor shaft – is positioned under each spark plug high tension terminal in turn as each high voltage surge is ready to be delivered to a particular plug forces the breaker point rubbing block which rides on it to open and close the contact points causes the distributor cap to move back and forth as the spark advance mechanisms change the timing.

  • This article is just a informative article which is important to classic car users to know how Distributor Cap and Rotor for Classic Cars are working. If you have more other info or troubleshoot please keep a comment below in comment section. Always appropriate your thoughts for Antique cars website. 

Article Source : Distributor Cap and Rotor for Classic Cars  article courtesy should goes to Auto Mechanics Autodology – Technical instruction manual by System Operation Support.