Distributor cap

A distributor is an electric and mechanical device used in the ignition system distributor cap older spark ignition engines. The distributor's main function is to route electricity from the ignition coil to each spark plug at the correct time.

Distributor caps and rotors are responsible for passing the voltage from the ignition coils to the engine's cylinders in order to ignite the fuel-air mixture inside and power the engine. The coil connects directly to the rotor, and the rotor spins inside the distributor cap. When the rotor's tip passes a contact on the cylinder, a high-voltage pulse travels from the coil to the cylinder via the rotor. That pulse jumps the little gap between contact and rotor and moves on to the spark plug wire, eventually igniting the spark plug on the cylinder. Because of all the high-voltage activity, the rotor and cap have to be replaced relatively frequently. They wear out easily.

Distributor cap

A distributor cap is a removable component that is used in spark ignition systems to cover both the distributor and the rotor. In addition to covering these components, and protecting them from contamination, distributor caps are also responsible for helping to distribute electrical current from an ignition coil to a set of spark plugs. Since distributor caps are wear items, they have to be replaced periodically as they wear out. A distributor cap contains internal contacts and corresponding external posts. Although distributor cap designs can vary from one application to another, they all share a few basic components:. The main body of a distributor cap is typically made from molded plastic that has a number of metal components built into it. A typical cap has one metal contact and post per cylinder and one central contact and post for the coil. The central contact is typically a spring-loaded carbon brush that mates with a central contact point on the rotor, which allows it to remain electrically connected while the rotor is spinning. The other contacts are spaced evenly around the perimeter of the cap, which allows the rotor to touch them as it spins. Rather than having a central contact and post for the coil, some caps have two internal contacts.

Automotive News Turn signals on a car's touchscreen? If any contaminants are able to get inside the cap, distributor cap, they may interfere with its ability to distribute the high voltage pulses that it distributes to the spark plugs.

JavaScript seems to be disabled in your browser. You must have JavaScript enabled in your browser to utilize the functionality of this website. View as:. Green Spark Plug Co. Ltd has now added a dedicated sales and distribution team to handle customers questions and pre-sales enquires, we are experts in our field so if you have a query let us know!

The Jalopy Journal. Terms of Service. Privacy Policy. Log in or Sign up. Atomic Industries www. Register now to get rid of these ads! The H.

Distributor cap

Although distributors are not common in modern vehicles, a distributor cap on older model vehicles connects the spark plug wires and distributor, and also protects your distributor's internal components. Distributor caps feature metal contact points on the underside, and when they are contacted by the rotor, this links the ignition coil's voltage to the proper spark plug to provide the power needed to create a spark. This is timed appropriately to ensure the rotor connects power to the spark plug at the appropriate time for combustion. With time, a distributor cap and its contacts may wear and fail under the stress of constant exposure to high voltage. If the distributor cap's contact points are worn down enough, it may not contact the rotor consistently, which can cause misfires or failed starts. The distributor cap may also be damaged or crack, which can allow moisture into the distributor housing and lead to corrosion or other damage.

Everton f.c. vs a.f.c. bournemouth standings

Most distributors used on electronic fuel injection engines use electronics to adjust the ignition timing, instead of vacuum and centrifugal systems. As the electrified tip passes each output contact, the high-voltage electricity is able to 'jump' across the small gap. Share this: Email Print Share on Tumblr. Up Next:. Mobile Newsletter chat close. You must have JavaScript enabled in your browser to utilize the functionality of this website. Breaker arm with contact points at the left. Categories : Electric power distribution Engine components Ignition systems. Sponsored Links. You can order from our website or phone us for technical advice. The Green Spark Plug Company is a family run business with over 40 years of experience. The other contacts are spaced evenly around the perimeter of the cap, which allows the rotor to touch them as it spins.

Home » Engine.

Green Spark Plug Co. Rather than having a central contact and post for the coil, some caps have two internal contacts. Shop By. The number of contacts in this case 4 is the same as the number of engine cylinders. A few signs of a faulty distributor cap include difficulty starting your car, shaking, stalling and hearing a yelling noise. Hidden categories: Articles with short description Short description matches Wikidata Articles needing additional references from January All articles needing additional references Articles with GND identifiers. Article Talk. These posts are then connected to two spark plugs per cylinder via spark plug wires. Download as PDF Printable version. Tools Tools. These components are wear items, which means that they are expected to wear out after a certain amount of time or usage.