In my rebuild I finished painting and upgrading the engine compartment. I replaced the voltage regulatior with a modern one. The regulator has this thing (looks like an interference or noise filter for the radio) that shares a screw and one wire from the alternator plugs in to the filter. The wire rusted out of the filter. Questions I have: Does this even matter? I happen to have a generic filter in the garage should I just use that? Am I right that it is a noise filter?
I am pretty sure that it is a noise filter. If you can't find one.....I probably have some. I can throw it in the box with the radio. Let me know.
You don't need the noise filter. Alternators do not produce the noise that generators did in the past. The filters were developed for those old generators. The slip rings and brushes make far less arcing than the generator's commutator and brushes that were making and breaking connections with arcing occurring at each bar. There is a capacitor filter in your alternator that does the same job as the external filter. If you have digital equipment connected to your charging system then you should filter the equipment but I doubt your radio will pick up interference from the charging circuit when there is so much radiated noise from the ignition.
Noise filter is on an as needed basis. With an alternator, you will hear whine more than noise pulses. Also depends on if the regulator is solid state or menchinical. In my 1990 car, the system uses a solid state regulator and a noise capacitor from the factory.
