superhawk996 Posted October 17, 2023 Share Posted October 17, 2023 A customer's '67 Vette, all original with a 327 and 4 speed. It's a low mileage weekend toy. It initially had a bit of a hiccup under acceleration and got worse somewhat quickly to where he was barely able to keep it running to get it home. He thought it was a fuel problem, but doesn't really know much about cars. Spark was cutting out in a strange way. It wasn't a normal misfire/rough running issue, it was as if there was an off button that was being sporadically pressed. Spark would go out briefly or long enough to stall the engine from high RPM. It was also off and on during cranking, sometimes staying off for several seconds. The points were a little out of adjustment and had mild pitting so I gave them a quick clean and set the dwell, no change. Coil power, distributor ground, all connections, and dwell stayed consistent even during spark out events so I figured it must be something going on in the coil. New coil, no change. At one point I found that with the points open the circuit wasn't open, there was around 100ohms across what should have been an open circuit. I pulled the points out, couldn't find anything wrong, reinstalled, verified they gave an open circuit, still no change. Last resort before telling him to tow it to a shop, I replaced the points and it runs like new. Quote Link to comment Share on other sites More sharing options...
tomek Posted October 17, 2023 Share Posted October 17, 2023 This post clearly shows why eliminating points ignition systems was greatest thing ever in automotive world. Quote Link to comment Share on other sites More sharing options...
XXitanium Posted October 17, 2023 Share Posted October 17, 2023 ...and condenser? Quote Link to comment Share on other sites More sharing options...
blackhawkxx Posted October 17, 2023 Share Posted October 17, 2023 Maybe you improved the connection by removing them. Any type of corrosion at connection points? Quote Link to comment Share on other sites More sharing options...
jon haney Posted October 17, 2023 Share Posted October 17, 2023 5 hours ago, XXitanium said: ...and condenser? That's what I was thinking, but I would have replaced the points first thing, just because they are not known for reliability, and are normally pretty cheap. Haven't bought any in a very long time, so maybe they aren't cheap anymore. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted October 17, 2023 Share Posted October 17, 2023 Unless one wants to experience the full charm of 1950's automotive technology and all of the bad that goes along with it, points are just an ugly memory. I can't imagine owning a points distributor that hasn't had a Pertronix Ignitor installed. https://pertronixbrands.com/collections/ignitor 1 Quote Link to comment Share on other sites More sharing options...
blackhawkxx Posted October 18, 2023 Share Posted October 18, 2023 (edited) 2 hours ago, IcePrick said: Unless one wants to experience the full charm of 1950's automotive technology and all of the bad that goes along with it, points are just an ugly memory. I can't imagine owning a points distributor that hasn't had a Pertronix Ignitor installed. https://pertronixbrands.com/collections/ignitor Maybe everyone is spoiled now? My 78 Subaru had points and every 10K I would check them plus the spark plugs would get swapped out often because of the leaded gas and being regular style but it only took a couple of minutes and really wasn't a hassle to me. With the old style ignition you could almost always get it to run at lest somewhat, with the new stuff, when it dies you ain't going anywhere. Saying all of that, yes the new stuff works better. Edit to add: I just remembered my Falcon had a Accel race dual point that was good for 10,000 rpm and seemed to work well. Edited October 18, 2023 by blackhawkxx Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 2 hours ago, IcePrick said: Unless one wants to experience the full charm of 1950's automotive technology and all of the bad that goes along with it, points are just an ugly memory. I can't imagine owning a points distributor that hasn't had a Pertronix Ignitor installed. https://pertronixbrands.com/collections/ignitor I put a Pertronix in my sandrail. I made it about 5 miles downhill from camp when it died. Luckily I had the old points with me along with tools. I never did get around to properly gapping them, the precision eyeball setting ran perfectly for the rest of the season and then I sold it. Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 10 hours ago, XXitanium said: ...and condenser? I installed new points and condenser, then swapped the old condenser back in to know for sure and it worked fine. It was the points, but I put the new condenser back in before wrapping it up. 1 Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 5 hours ago, blackhawkxx said: Maybe you improved the connection by removing them. Any type of corrosion at connection points? No corrosion. I removed and re-installed the old points with no change and had the wire off of them several times while testing stuff. The only cleaning I did before installing the new ones was to clean the cam before applying the new grease. Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 58 minutes ago, blackhawkxx said: Maybe everyone is spoiled now? My 78 Subaru had points and every 10K I would check them plus the spark plugs would get swapped out often because of the leaded gas and being regular style but it only took a couple of minutes and really wasn't a hassle to me. With the old style ignition you could almost always get it to run at lest somewhat, with the new stuff, when it dies you ain't going anywhere. Saying all of that, yes the new stuff works better. Edit to add: I just remembered my Falcon had a Accel race dual point that was good for 10,000 rpm and seemed to work well. My '78 CVCC had points, my parents bought it new. I don't recall it ever having a points issue. Electronic is all or nothing with no warning. I've never had points suddenly fail, this instance was the closest to that giving a somewhat short warning accompanied by several stalls. It had really cheesy looking Standard Ignition brand points. I installed 'standard duty' Accel, they also have a high RPM version but this thing can't out-rev the standard ones so it would be dumb to run the high tension spring. 1 Quote Link to comment Share on other sites More sharing options...
XXitanium Posted October 18, 2023 Share Posted October 18, 2023 1 hour ago, superhawk996 said: I installed new points and condenser, then swapped the old condenser back in to know for sure and it worked fine. It was the points, but I put the new condenser back in before wrapping it up. What causes that electrically? I'm old enough to have had a bunch of cars with points back in the day. I don't understand the process that would make that happen at higher rpm. Weak spring, abraded wire/increased resistance? Google... GM... https://www.ffcars.com/threads/cutting-out-at-higher-rpms-solved.3548/ A set of points is a cheap resolution though. Did you use a matchbook cover to set the gap? Quote Link to comment Share on other sites More sharing options...
IcePrick Posted October 18, 2023 Share Posted October 18, 2023 1 hour ago, superhawk996 said: I put a Pertronix in my sandrail. I made it about 5 miles downhill from camp when it died. Luckily I had the old points with me along with tools. I never did get around to properly gapping them, the precision eyeball setting ran perfectly for the rest of the season and then I sold it. Huh. I had Pertronix in boats, cars, trucks... never a single problem with them. They used to be much cheaper, too, I see they're around $100 now, I think they were around $40 back then. Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 (edited) 11 hours ago, XXitanium said: What causes that electrically? I'm old enough to have had a bunch of cars with points back in the day. I don't understand the process that would make that happen at higher rpm. Weak spring, abraded wire/increased resistance? Google... GM... https://www.ffcars.com/threads/cutting-out-at-higher-rpms-solved.3548/ A set of points is a cheap resolution though. Did you use a matchbook cover to set the gap? In this case I believe there was something in the points allowing an electrical path to ground when they opened weakening the trigger to the coil. I was only able to measure continuity once and that's what lead me to suspect them. Even tho statically it was an open circuit every other time I checked, the voltage created at the moment of the points opening could jump a small gap which could cause it to not trigger the coil properly. The triggering was good enough to make the dwell meter show that the points were working, but I can imagine how the magical pixies could tell the meter "all's good" while not giving the coil what it needs to make a spark. I assume this problem could be measured with something, maybe an oscilloscope(?), but I don't think any of the meters I carry could have detected it. If they could, I don't know how to do it. I initially eyeballed the gap, then set them with a dwell meter which is the most accurate way. My eyeball was about one degree of dwell off, well within tolerance, but I went for the exact 30 degree setting. Edited October 18, 2023 by superhawk996 Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 18, 2023 Author Share Posted October 18, 2023 11 hours ago, IcePrick said: Huh. I had Pertronix in boats, cars, trucks... never a single problem with them. They used to be much cheaper, too, I see they're around $100 now, I think they were around $40 back then. It's possible that something on the engine killed them, but I think everything was set up right. I remember reading something about the voltage, or coil resistance, or something being somewhat important. After it shitted out I read many forum threads about them dying. Maybe it's just a VW thing. It's also possible that it wasn't a Pertronix brand device, I can't say for sure. Quote Link to comment Share on other sites More sharing options...
ironmike Posted October 18, 2023 Share Posted October 18, 2023 Mechanical advance (or early vacuum)? Dwell should be set at 30* (factory spec). Check the distributor advance plate, weights, & springs (under the points/condenser plate). One or more broken springs (there should be 2 springs & 2 weights) can cause those symptoms. The weights are subjected to increasing centrifugal force as rpms increase flinging them outward; springs' strength fights this thereby affecting & limiting the advance timing. A broken or worn-out spring(s) can play havoc with the spark timing (worse under a load). If its a vacuum activated advance system, check the vacuum hose (dist to carb/base) as well for any leaks or dry rot. Replace the entire vacuum line if necessary. The 327 small block is pretty damn reliable; it wants to run even if it's been abused or the timing is way off. Scrutinize that distributor advance; I'd be surprised if it's not something that simple. 1 Quote Link to comment Share on other sites More sharing options...
The Krypt Keeper Posted October 19, 2023 Share Posted October 19, 2023 On 10/17/2023 at 11:20 AM, XXitanium said: ...and condenser? Always carry spare ones now for the 28 Model A, even the shortproof ones are subjected to extreme heat and go "poof" Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 19, 2023 Author Share Posted October 19, 2023 4 hours ago, ironmike said: Mechanical advance (or early vacuum)? Dwell should be set at 30* (factory spec). Check the distributor advance plate, weights, & springs (under the points/condenser plate). One or more broken springs (there should be 2 springs & 2 weights) can cause those symptoms. The weights are subjected to increasing centrifugal force as rpms increase flinging them outward; springs' strength fights this thereby affecting & limiting the advance timing. A broken or worn-out spring(s) can play havoc with the spark timing (worse under a load). If its a vacuum activated advance system, check the vacuum hose (dist to carb/base) as well for any leaks or dry rot. Replace the entire vacuum line if necessary. The 327 small block is pretty damn reliable; it wants to run even if it's been abused or the timing is way off. Scrutinize that distributor advance; I'd be surprised if it's not something that simple. Mechanical and vacuum, like most distributors have. Advance mechanisms can cause running problems, but won't cause the spark to stop like this was doing. It was the points. Both advance mechanisms work properly, nothing left to scrutinize. Quote Link to comment Share on other sites More sharing options...
OMG Posted October 20, 2023 Share Posted October 20, 2023 On 10/17/2023 at 8:40 AM, tomek said: greatest thing ever in automotive world Or disc brakes Southerners would say AC Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 20, 2023 Author Share Posted October 20, 2023 The greatest thing for the automotive world was the internal combustion engine, and now trying to take that away too. 1 3 Quote Link to comment Share on other sites More sharing options...
CALCXX Posted October 22, 2023 Share Posted October 22, 2023 (edited) Makes me wonder about the insulator on the pivot post since you said it was not open. (grounding the points) You also said it just quit. I think it should have backfired if the points are grounding. Condensor would have drained also. Edited October 22, 2023 by CALCXX Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 22, 2023 Author Share Posted October 22, 2023 12 hours ago, CALCXX said: Makes me wonder about the insulator on the pivot post since you said it was not open. (grounding the points) You also said it just quit. I think it should have backfired if the points are grounding. Condensor would have drained also. It never backfired or ran noticeably rough, it seemed to run perfectly or nothing. Hard to say for sure because it runs somewhat rough when cold, but it wasn't obviously worse than normal. Watching my timing light connected to the coil lead it wasn't a 'sputtery' spark, it would be on, off, then on again. Quote Link to comment Share on other sites More sharing options...
CALCXX Posted October 23, 2023 Share Posted October 23, 2023 I see why you replaced the coil. You said that didn't help. Quote Link to comment Share on other sites More sharing options...
superhawk996 Posted October 24, 2023 Author Share Posted October 24, 2023 I still have the points and just put my ohm meter on them again, they seem to be fine. So strange. I wish I had an engine I could put them in to re-test. Maybe I need to buy a C2 instead of that C4 we were talking about 😆 1 Quote Link to comment Share on other sites More sharing options...
XXitanium Posted October 25, 2023 Share Posted October 25, 2023 ...or a 442? 1 Quote Link to comment Share on other sites More sharing options...
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