If you are running with resistance voltage to the ignition coil in Run position, and the points and/or coil(s) keep failing, you may have a condenser that needs to be replaced. I had always heard from "old timers" (back when I was young) that the purpose of the condenser was to keep the points from
arcing and burning up too soon. In later years, once I got back into pony cars after my "life happened" years of raising a family were behind me (and I became an old timer), I began to ponder how it is the condenser really behaves. I have recently acquired a really nice MicSig 4 channel digital oscilloscope, and am still learning how to set it up and use it for automotive electrical systems. In order to play with it inside our warm home, as opposed to in our frigid, Winter temp garage, I set up a bench ignition system with both primary and secondary circuits so I could tinker with an ignition system while analyzing spark generation, coil flux saturation, and flux collapse patterns, etc. But the first shortcoming I ran into was in getting an adjustable power supply that only produces 5 amps (my bad, I should have looked at the amps spec, not just the voltage). I am able to get coil saturation and flux field collapse patterns, but there is not enough amperage even with 10-12 volts (much less 9.5 volts) to produce a secondary spark. I get the output voltage potential to build, but not with enough oooomph to produce the kind of power and voltage to really kick out the juice needed to jump even a 0.010" or 0.005" spark gap. So, another, higher amperage power supply is on order. I dare not bring an automotive battery into the house, although that would solve the source capacity issue. Lynda is a Mustang/Shelby Chick, and enjoys working with me on our vintage cars. But, to begin dragging in larger parts, especially a lead acid battery, would push things too far - I dare not even try her patience like that, even though the thought admittedly did cross my mind for a very short moment <heh heh>. As it is she has been a good sport about me getting a vintage Sun Scope, more recently the MicSig oscilloscope, as well as an Xtools D7 high end OBD2 scanner the other day (Yeah, I have some cool toys). So the fun time in producing the "Zzzzzap" of a secondary output spark will have to wait a few more days.
Meanwhile, I am able to see enough in the primary circuit how the voltages behave to let me get my mind wrapped around what
may really be going on with the voltages, leading me to feel the condenser really is quite important. This is a long way for me to say that I believe your condenser needs to be replaced, assuming your coil voltage is indeed around 9.5v in Run mode. Here is what I am seeing (
sorry, no photos of the spark or circuit patterns from the digital scope, as I have yet to learn how to pull images from the scope, that is a feature, but...). When an electrical current is introduced into the coil primary windings a flux field builds fast enough to cause the secondary circuit to become activated with a high voltage potential. I have felt for years one of the reasons for the condenser was to slow the flux field build enough to reduce or eliminate (by "buffering" the saturation period) the propensity for the saturation phase for the coil to build up a secondary current sufficient to allow an arc to jump a spark plug gap. I do see a spike in the secondary circuit upon current saturation when I use a manual on/off momentary, spring loaded button (normally open, button press closes the circuit). And when I release the button, opening the primary circuit, the current ends which causes the flux field to collapse. Well, the instant, unbuffered, collapsing flux field is what causes the
secondary circuit to build its high voltage meant to cause an arc at the spark plug gap. But, the same collapsing flux field also cuts across the
primary ignition windings in the coil, and I see anywhere from 160 to 200 volts being built and collapsing in the primary circuit. That would be enough to causing sparking or arcing at the points. But, when I remove the condenser from the primary circuit there is clearly a higher level of primary circuit activity. My gut tells me once I crank up the amperage sent to the primary circuit with the new power supply, that higher level of primary amperage is going to increase both the primary and secondary current levels significantly. Perhaps enough to cause enough "unbuffered" voltage to arc the points more than normal, and perhaps to even cause the coil to overheat due to the heavier than normal levels of current to flow over a shorter period of time than when a condenser is connected to the system.
Until I get the new, higher amperage output power supply, and learn how to grab photos/images of the bench ignition system on the table in our living room holding all the equipment and circuitry, I won't know for sure how critically the condenser is actually impacting the primary circuit. But, I do know this. If you are running about 9.5 volts in Run mode (it is worth double, even triple checking that), it is not normal for points, much less an ignition coil, to need replacement frequently. In "the old days" I would have suggested replacing points and condenser (after checking the coil voltage) every 12,000 miles or so (and plugs also). And that worked out pretty well. I do remember getting a car in our Ford dealership shop that had a bad condenser. In its case it prevented an ignition system from working, but I believe that was a condenser that had an internal short to ground, so the flux field for the coil could not build and collapse as needed to fire the spark plugs. I never saw a set of points that got fried, or a coil that failed, due to a bad condenser. But, in the back of my mind I was always on the lookout for that condition.
Anyway, HemiKiller (above) mentioned using Standard brand points. I like Standard also. Back "in the day" I was also a big fan of Blue Streak brand primary ignition parts. They had a fabric wick (LubriWidk) that would rub on the distributor point cam lobes to help disperse a very, very thin coating of ignition point rubbing block grease. That was supposed to help prevent excessive rubbing block wear, where inadequate lubrication would lead to the gap for the points to close up, which essentially caused engine timing to retard, caused a weak coil saturation, and caused points to arc more than normal. I always felt their focus to attention like that (lubricating wick) was a smart thing to do. And I never had problems with their points (or condensers). In looking at a recent web site where Blue Streak points are sold it looks like they have held to their use of their LubriWick feature. Nice move on their part.
https://catalog.zodiac.nl/en/05-engine-electrics/ignition-parts/blue-streak-points-condensers-and-kits-1240
Once I get the higher amperage power supply, and am able to produce spark plug gap jumping high voltage sparks I may circle back to this thread just to update what I have been seeing with primary circuit behavior with and without a condenser of a properly powered ignition system primary circuit. I can hardly believe how much fun I am having with all these new fangled toys... heh heh...
