I’ve been wondering about this for years. I know a good amount about engines, I’ve even read a couple of books on them and have NEVER come across a definition for points. They don’t even talk about them yet I hear people all the time talk about them saying stuff like I needed to change my points etc.
I know it has something to do with the ignition system and I’m guessing it has something to do with the distributor but don’t know exactly what. so help a poor guy out will ya?
The best I can describe them to you are the points inside your distributor that the rotor contacts as it turns, completing the circuit to the spark plugs, enabling them to fire in the proper sequence. I’m sure someone else will be along shotly to give you a much more technical description.
In an older car with a traditional distributor, the points are an intermittent switch that open and close via the action of a cam lobe on the central rotating shaft of the distributor. They were also known as breakers.
The points usually consisted of two copper “contact pads”, that were mounted on a hinged plate, which was adjusted by hand to ensure that the points closed at the appropriate time and duration for correct ignition timing. Adjustment was often done by hand, using a stroboscopic timing light. Usually the distributor body was rotated to advance or retard ignition timing while the engine was running, and the aalignment was checked with the strobe light against timing marks printed on the engine block and fan assembly.
It was essential to pre-adjust the points gap with a feeler gauge when fully open prior to starting the engine.
Obviously, one also needed a workshop manual to get the correct values for the points gap and ignition timing.
These days, the job of the points is done electronically within the distributor - the “breakerless” distributor. The fine-tuning of ignition timing and duration is now done continuously by the computer.