watson

I took my 67 out yesterday and it had a strange problem. It first died at a stop light and it was hard to start. When it did start, it did not want to idle. I decided to head home and noticed that the amp gauge was pegged at the max when I was driving at about 2500 RPM. I turned on the lights and it came down, but it was still way too high for normal. At the next stop, it died again an this time it would not start. I had it towed home and I plan to troubleshhot it next week. My first thought is that the voltage regulator gave up and the high voltage fried my electronic ignition. The plan is to drop my spare distributor in the car (with conventional points) and see if it will start. If so, I will check voltage at the battery. I think that will show me if the regulator is bad. Does that sound like a reasonable plan? I admit that I am an idiot when it comes to electrical systems.

Thanks,

Doc

69427

What system do you have?

watson

I have the PerTronix after market ignition.

Doc

wadenelson

Slow down there Doc. With a voltmeter check your battery. 12.6 is fully charged, 12.3 is 50% discharged, 12.1 is 90% discharged. If it's below 12.6 put a battery charger on it. Don't worry if it ends up above 12.6, that's what's called a "surface charge" and boils off the second you turn on the headlights for 30 seconds.

Now that the battery is charged, take it out, take it down to Autozone or your favorite battery store and have it load tested. It can be fully charged and still no damn good. How old is it? A battery is like a swimming pool that gradually gets filled up with silt and the fill/drain pipes get clogged as well until it simply can't flow enough water in and out fast enough.

Your amp gauge being pegged (probably) just means your alternator was trying to recharge a very low battery. All you did by turning on the lights was to divert some of that 55 amps the alternator is capable of putting out toward the headlights instead of the battery. (The ammeter only measures what's flowing between the alternator & the battery, power to the headlights goes directly from the alternator to the headlights and sneaks its way around the shunt used for the ammeter)

Once you know you have a healthy, charged battery, THEN we can worry about a failed or failing voltage regulator, etc.

Quite simply, with a fully charged, HEALTHY battery, rev the motor up to 2000 rpms and if the voltage you measure across the battery terminals is 13.5 or better your alternator and voltage regulator are working properly. Over 15.5 your regulator is not working right.

I rather doubt ANYTHING is fried. Probably just due for a fresh battery. Good luck and post again if its more serious.

watson

I thought of that as well. I the battery is almost new and I did check it with my tester. It shows to be good, plus it cranks the car over with no problem.

Doc

65GGvert

Your first assumption is possible. The voltage regulator can be bad and cause the alternator to try to charge 17 or 18 volts and that would peg your battery gauge. It can also destroy your Pertronix. If it starts with the points distributor in, measure the voltage at the battery with the engine running. If it's not in the 13-14 volt range, you'll know. You can buy a solid state voltage regulator at most any auto parts store that will plug in your current connector. VR715 is the part # and it's around $20 something bucks I believe. I keep one for eliminating the VR when I suspect it on my cars and when others ask for help in the area.

wadenelson

If you've already vetted the battery then it's time for simple no-start diagnosis. Is it fuel or is it ignition that's lacking. A squirt of starting fluid / ether will quickly reveal if you have a fuel problem, fuel contamination, whatever. "Won't idle" sounds more like a fuel/air problem, unless the battery was so low it couldn't fire the plugs.

Then check to see if you've got 12V across the coil when you turn on the ignition. Loose wire? Blown fuse?

After that, then pull a spark plug wire and look/listen feel? for spark. Only after that would I swap in a points distributor. Check the easiest things first If your system actually hit 17-18V your headlights would probably be burned out as well as your coil.

65GGvert

There's no fuse in the ignition circuit. The fuel mix and spark won't cause the battery gauge to peg. Unless you suddenly developed multiple problems simultaneously, I'd start with the battery/alt/charge checks. Easy enough to try what I said earlier, measure at battery with and without engine running.

kellsdad

with 65GGvert.

watson

Thanks everyone, I hope to spend some time on the car today. I have confirmed that fuel is not an issue. I guess that my basic question was if a bad regulator could fry my ignition. I do plan to start by confirming that I do not have spark and that it why the car will not start. If that is true, I will try using the points distributor and see if the car will run. Then I can try another regulator I did see that Corvette Pacifica has a solid state electronic regulator kit that is designed to fit under the stock cover. Has anyone used one of those?
Thanks,
Doc

65GGvert

Measure the voltage at the battery and at the positive wire on the coil.

seb67

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