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Zymurgy

Zymurgy

Old Man with a Hat
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Drove home from Nats last weekend, when I got off the freeway I noticed my alternator gauge going crazy(not the typical movement) it would go clear to the top and then center in did this the rest of the way home 2 miles.

Benched the alternator OK, put old voltage regulator on, perfectly steady I thought my problem was solved, but only started and idled it, I didn't take it for a drive.

Was going out for pizza last night. It started fine, drove 3/4 mile died and acted more like it wasn't running on all cylinders. You could not keep it running, it kept dying. Definitely not fuel starved trust me I know what that is after all I went through this spring.

Here is the odd thing if it sat for 15-20 minutes. It would start and run fine for about 30-40 seconds. Now I have 2 theories does ballast resistor or fuse-able link fit either of these symptoms.

Ironically I still have the original of both.
 
The first place I would look at is the bulkhead connector. I had a similar problem and I changed everything I could think of without any success. When I took everything apart when I restored the car I discovered the bulkhead connector was very dirty and one pin was badly corroded. That pin was used to pass through the wire from the ammeter to the starter relay and the fusible link. It was nasty and very close to causing a fire.
 
Coil. Had the same thing happen to me on my 75 Chrysler. Was a brand new coil too. Was getting too hot.
 
Well I have tried all three. Still the same.

I forgot to clamp the distributor cap down a few weeks ago and it jacked the tab up on the rotor where the rotor meets the top of the distributor. IMG_20150815_125659460.jpg
IMG_20150815_125710134.jpg

IMG_20150815_125659460.jpg


IMG_20150815_125710134.jpg
 
Zymurgy said:
Drove home from Nats last weekend, when I got off the freeway I noticed my alternator gauge going crazy(not the typical movement) it would go clear to the top and then center in did this the rest of the way home 2 miles.

Benched the alternator OK, put old voltage regulator on, perfectly steady I thought my problem was solved, but only started and idled it, I didn't take it for a drive.

Was going out for pizza last night. It started fine, drove 3/4 mile died and acted more like it wasn't running on all cylinders. You could not keep it running, it kept dying. Definitely not fuel starved trust me I know what that is after all I went through this spring.

Here is the odd thing if it sat for 15-20 minutes. It would start and run fine for about 30-40 seconds. Now I have 2 theories does ballast resistor or fuse-able link fit either of these symptoms.

Ironically I still have the original of both.
Click to expand...


I'll guess that you have electronic ignition system. If not, you can ignore this answer.

Check your battery voltage. Your alternator is NOT charging, causing low battery voltage. When the battery voltage gets down to a certain point, the electronic ignition control unit will not fire correctly. Basically the transistor needs a minimum voltage (close to 13 volts) to operate and fire the coil, hence it acting like it isn't firing on all cylinders. Once you let the battery sit for 15-20 minutes, it recovers just enough voltage for the transistor to operate properly again, but not for long as the battery will drain down once again pretty quickly causing it to once again start mis-firing. Eventually, the battery voltage will be low enough that the engine will just crank slowly and not fire at all.

Check your charging system again, suspect the VR that you put on first. Good luck!
 
Mopars & Missiles said:
I'll guess that you have electronic ignition system. If not, you can ignore this answer.

Check your battery voltage. Your alternator is NOT charging, causing low battery voltage. When the battery voltage gets down to a certain point, the electronic ignition control unit will not fire correctly. Basically the transistor needs a minimum voltage (close to 13 volts) to operate and fire the coil, hence it acting like it isn't firing on all cylinders. Once you let the battery sit for 15-20 minutes, it recovers just enough voltage for the transistor to operate properly again, but not for long as the battery will drain down once again pretty quickly causing it to once again start mis-firing. Eventually, the battery voltage will be low enough that the engine will just crank slowly and not fire at all.

Check your charging system again, suspect the VR that you put on first. Good luck!
Click to expand...

Boy that sounds just like my problem, but I still have points and a condenser.
 
A number of things fit your description. Basically it sounds like a breakdown in your high voltage, through a bad component, loss to ground, or loss of contact due to a bad connection.

The condenser might be breaking down under load. Might also be a crack somewhere in the distributor cap.

Also check all the coil and distributor connections as it could be simple corrosion or a thermal issue: as it heats up, something loses contact, ground, etc. WD-40 is handy for cleaning up contact areas as well as removing moisture from wires, cap, etc.

Feel the coil after it runs for a while and see if it's hot. If it is, it could be a defective coil or the ballast resistor could have changed value which is allowing more draw on the coil. Unlike a typical resistor that would burn up if overloaded, ballast resistors are designed for load dropping(dissipating extra energy through heat) so unless they get really hot, they won't show any sign of damage. It's not likely, but possible that it changed value which would alter the voltage to the points and cause problems. Check the contacts for pitting from arcing over.

Sounds like a lot to check but it's not too bad. You could just shotgun the entire system but unless you find something obvious, you'd never know what it was. I'd go through and check & clean all my connections for the distributor/coil first. Then swap out the condenser, it's the cheapest place to start if you don't have a spare handy. Check your coil wire, too.
 
I can't believe we have had so many ignition problems on this forum with a very reliable and simple Mopar ignition system. I've had coil, ballast resistor and ignition module troubles myself and keep a spare set of all of the above in a tote in the trunk since I drive the NYB cross country several times a year.
 
Great advice guys! Maybe your distributor cap needs to be inspected more closely after the dance it did.
 
I think you have two different problems. The charging issue is most likely a voltage regulator problem. I'll bet the points are sticking closed intermittently. There's no alternator failure that could cause this.

The ignition problem could be a lot of things.... If you are still using that rotor you need to replace it obviously. Check point gap etc. If it continues, think about bypassing the wiring to the ignition switch with a jumper from the battery to the ballast resistor to test it.
 
I think the voltage regulator is new, right?
 
I would pull the plugs and inspect them. Dumping raw fuel with the ignition problems,may have fouled a plug,or even more than one.
 
I learned the hard way about fuseible links in a situation like yours. It would only cause resistance with a build up of heat. Pop a new one in.
I would inspect the bulkhead plugs, no scratch that, I would pull the bulkhead plugs and clean them with a little wire brush.
Also, seriously think about one of these.
http://www.ebay.com/itm/like/201249071310?ul_noapp=true&chn=ps&lpid=82
 
A bad coil can give you the same symptoms as a bad carb or fuel delivery problem. An old timer told me this decades ago when I had my first car and that advice saved me hours of frustration. I also agree with checking your bulkhead connections. They are a known weak link in our beloved Mopars and have been the cause of many electrical fires. Is your voltage regulator the original breaker point style or have you upgraded it to the newer solid state unit. The newer style looks identical to the OEM but has more reliable solid state circuitry. Hope this info helps.
 
Hallelujah problem solved! It was the condenser. I have changed out a bunch of condensers in my life this is the first time I think it was ever bad
 
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