Instant loss of charging... car is now dead on road...

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805moparkid

805moparkid

Slant and AFX Guy
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ok so today i installed my vacuum gauge and the wideband o2 setup...

played around in the drive way for quite awhile so the car was running and charging fine...

so out to finally test it and i get about a mile and my volt gauge is dropping fast and AMP gauge is in the middle with no movement (which is odd on its own as its always bouncing)

anyways so i pull off thinking i may have thrown a belt... i get off the road and check it out... belt is fine!?!

so a guy gave me a jump and by the time i got in it to go it died again... no charging...

i checked all the leads, are are snug, nothings been messed with...

so get a ride home and grab the volt meter...

key on i have 11.62 volts at the battery. have about 10.5 on the out side of the volt reg, and 10.5 at the alt tab... got it running with a jump and with the other car still hooked up to keep it alive it said 28volts on the hot lead out of the alt??

what in the hell is going on? im really starting to lose it...
 
1st guess,,,,,,,,,,,,,,,,voltage regulator took a sheeeet not regulating overcharging,cooking the battery:glasses7:
 
I'd guess you have something like a bad connection in the bulkhead connector, the ammeter connections have "gone away" or the "in harness splice" has broken. Hey, it happens

For example, a break in the charging line from the alternator through the bulkhead to the ammeter circuit would result in high alternator voltage, and no charge.

ANY CAR should run for hours off the battery with no charging system. Hell, you should even be able to run it a FEW miles with the headlights on Sounds to me like you might have a battery on the way out, too.

First thing I'd do is get the battery charged and PROPERLY load tested.

Pull your bulkhead connector apart and inspect it

Read the Mad article: (which gives you a simplified diagram of the heavy current conductors in the harness

http://www.madelectrical.com/electricaltech/amp-gauges.shtml
 
Yea,but was the 28 volts with the booster cable attached??At this point the battery must be charged and checked that it don't fall below 9 volts with a load tester,then refire and check the voltage and ampage:coffee2:
 
I would double check your grounds are solid. You may have fried the battery and it is no longer taking a charge. Your going to have to check the voltage without the jumper cables to see what is going on. My only guess is that somehow with the jumper cables on it is acting like a series circuit versus a parallel circuit......reason for checking the grounds. I may be thinking this all wrong. hope you find the culprit though.
 
Did you check the voltage with the jumper cables hooked up and yours with the key in the off position? If your still getting the 28volts at your end then there is definately something wrong with your wiring integrity.
 
grounds are all fine... i have been going thru trying to figure out a top end miss and now this lol...

i will try as you guys asked...

thought i should throw in when it had a dead short in the horn circuit i had to re-wire most of the under dash and by passed the bulkhead... also a new 10ga lead from the alt to the amp gauge and from the amp gauge into the splice...
 
I had this same problem with a dodge pickup a few months ago. The ammeter is in series and mine went bad read dead center but the circuit was not complete because of the ammeter being popped. Also check your bulkhead connector for corrosion, terminal fittiment, pins backed out etc. after i bypassed my ammeter the right way and installed some fusable links inline mine charged around 14.5 all day long at the battery
 
tml89 said:
i had this same problem with a dodge pickup a few months ago. The ammeter is in series and mine went bad read dead center but the circuit was not complete because of the ammeter being popped. Also check your bulkhead connector for corrosion, terminal fittiment, pins backed out etc. After i bypassed my ammeter the right way and installed some fusable links inline mine charged around 14.5 all day long at the battery
Click to expand...
yup!!
 
tml89 said:
I had this same problem with a dodge pickup a few months ago. The ammeter is in series and mine went bad read dead center but the circuit was not complete because of the ammeter being popped. Also check your bulkhead connector for corrosion, terminal fittiment, pins backed out etc. after i bypassed my ammeter the right way and installed some fusable links inline mine charged around 14.5 all day long at the battery
Click to expand...

but if the amp meter pops NOTHING gets power right... as you said its in series and when i was in there is goes from the alt to amp gauge, then amp gauge to the big splice behind the gauge cluster...

will check for ohm rating but just asking...
 
No, I think it is just the charging system that runs through the amp gauge, I could be wrong.
 
I wish I could help out Kid, Creed had the same thing happen to the bands Van a 1986, and he took the alt of my ramcharger in hopes to get them on the road to Little Rock Thursday night they had to rent a U-Haul trailer ....... fast forward to Friday evening and there was a plug with 4 wires that ran threw and the large wire in it was toasted and broke off.. This was not in the bulk head.. I hope this is corrected soon and this low voltage could have been your reason for miss firing at top end. Good luck and I hope to see this thread turn to a found it post soon
 
StrokerScamp said:
No, I think it is just the charging system that runs through the amp gauge, I could be wrong.
Click to expand...

If ammeter is bad or wire connections are bad, no power. Loads are on "alternator" side of ammeter, only thing on opposite side is battery.
 
I wish I could get down to some of you guys. We'd have this wrapped up in "short" order. No pun intended.

FIRST thing I'd do is charge and test the battery, and replace it if need be. THEN you'll have a battery that will run the car "for awhile" and you can do some testing.

The real high voltage is not a good sign, that indicates the alternator is NOT solidly hooked to the battery, IE bad connection in the charging circuit. Broken connector/ wire right at the output stud, bad connections through the bulkhead, etc. Could even be a broken "in harness splice."
 
67Dart273 said:
I wish I could get down to some of you guys. We'd have this wrapped up in "short" order. No pun intended.

FIRST thing I'd do is charge and test the battery, and replace it if need be. THEN you'll have a battery that will run the car "for awhile" and you can do some testing.

The real high voltage is not a good sign, that indicates the alternator is NOT solidly hooked to the battery, IE bad connection in the charging circuit. Broken connector/ wire right at the output stud, bad connections through the bulkhead, etc. Could even be a broken "in harness splice."
Click to expand...

pun away lol... will be charging the batt at work today...
 
If you have a low resistance connection from the alt out to the battery, you can't read 28 V at the alternator. If you manually apply "full field" 12 V across the alt field terminals, it should read <15 V at the battery. If over-charging the battery, it will start breaking the water into H2 & O2 but the voltage won't go up.

Verify you have water to the top of all the cells, and the battery reads ~12.6 V with one lead disconnected.

Measure the resistance from "Alt out" to the "Batt +". Should be <1 ohm (subtract the reading w/ multimeter leads shorted together). You probably will measure an open circuit because your ammeter or bulkhead connector is a broken connection.

There are constant warnings on FABO to check, clean, or bypass the bulkhead connector. Many run separate wires around the connector. It looks like the factory did that in 64, based on mine. In 65, they used special thru lugs w/ clamps. Maybe 66+ they got the bright idea to run the high ammeter current thru the regular 57 terminals.

Regardless, your simple fix now is to run a 8 awg or larger wire direct from "Alt out" to "Batt+". Your ammeter will no longer work, but your battery will charge, if the alternator field wires to the Vreg are correct. Anybody more motivated can look up my post on using diodes to bypass my ammeter at high currents to protect it, but a higher threshold and don't blame me if things melt.
 
Last time I had to deal with this problem was with a to RR.Melted the wire on both sides of the bukhead.Now I can't remember how the circut goes,but part of the "power feed" also goes through the ignition switch:happy1:
 
Ok my guess is your alternator has a sperratic dead short in it. I had one like that and the symptoms were the same. The inside of the alternator is all jacked up is my guess. It had a high end miss too before it took a **** on me. Couldn't find out the problem got it running, revved it up and all kind of sparks and **** were coming from inside the alternator at about 4 k missing like a sumbitch. Replaced the alternator, walaaa all good.
 
BillGrissom said:
If you manually apply "full field" 12 V across the alt field terminals, it should read <15 V at the battery. If over-charging the battery, it will start breaking the water into H2 & O2 but the voltage won't go up..
Click to expand...

Bill that is only true on a battery that is "down." On a fully charged battery, and especially if you have a nice big alternator, such as 60A, you can EASILY drive the battery voltage right up there. I've done it many times
 
Mad Dart said:
So did you ever find out what the problem was??
Click to expand...

no i have other things i need to do so its sitting for now...

67Dart273 said:
Bill that is only true on a battery that is "down." On a fully charged battery, and especially if you have a nice big alternator, such as 60A, you can EASILY drive the battery voltage right up there. I've done it many times
Click to expand...


i have a 60 on mine
 
ok so i messed with the dart and this is what i got...

key off, no lights or anything on

Battery Volts 12.60v
Regulator 0v Ign side/ 0v Field side

Key on, not running

battery volts 12.07
Regulator 10.75v Ign Side/9.60v Field Side
Alternator Stud 0v/ Field Wire 9.48v

Running (electric pump on)

Battery Voltage 12.60v
Regulator 10.8v Ign Side/ 9.7 Field side
Alternator Stud 28V

NOTES

Regulator was warm after only 2 minutes of running

(baseline ohm reading for multimeter was .03ohms)
Starter Relay to Battery Positive lead had a .1ohm reading
amp meter has .83 ohm reading

also noticed amp meter dosn't move with turning on and off lights,pump, dosn't twitch with turn signal activation either

also pulled bulk head apart and still had the grease i had installed in 09, clean BTW...

will mention new alternator was installed in 2010, replaced reg at same time...

_____________________________________________________________

so what is next??
 
on a whim i also just tested the alt static...

0 ohms between the stud and field wire

BUT 3 ohms between the field wire and case!?!

think the alt is toast eh?
 
805moparkid said:
on a whim i also just tested the alt static...

0 ohms between the stud and field wire

BUT 3 ohms between the field wire and case!?!

think the alt is toast eh?
Click to expand...

Sounds like that may be the problem. The windings may be coming apart. I know mine did and the Brushes were flying everywhere when I revved it up hard.
 
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