Alternator not charging + multiple meltdowns…HELP!!!

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Three60Demon

Three60Demon

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Good evening, I thank those who read this whole post in advance.

here goes…

My ‘71 Demon has an externality regulated alternator, but when I discovered it was not charging I threw an internally regulated alternator on and assumed it would work fine. I assumed wrong. About a half a mile down the road I start smelling electrical smells and I start seeing smoke coming from under the dash. After returning the car home and blowing the dash apart, I found I had melted the lead 12v connection for the key (blue w/ white tracer.) I replaced the wire and managed to repair the bulkhead with hot glue. Being a broke college student unable to pony up for a quality repro harness, it is kind of imperative I keep the original. Some time goes by and I have some time to mess with the car again. I replaced the voltage regulator and still no charge. I then realized that the blue wire coming from the voltage regulator needs key-on 12v, but once I spliced a wire from the fuse box to that blue wire, my new wire burned up and the 12v wire for the key I had recently replaced started to melt as well. Right now the car just runs on the battery, and even with a full charge it doesn’t run the same as it once did. It loses power under load and even just putting around. I’ve lost turn signals as well. Any tidbits of information or possible solutions to my problem would be greatly appreciated.

important details to note:
- originally a /6 column auto converted to 360 and a833 (non v8 engine harness)
- MSD 6AL ignition box and pro billet distributor
- Digitails LED taillights
 
Step one: stop splicing ****.

Step two: get a diagram, make it match that.
One wire at a time, with the battery disconnected. After each wire, hook up battery, verify no melty smoky sparky sparky.

My guess is, since you're not blowing fuses as you should, is that the wires are melted through and shorted inside the harness somewhere.
 
You lost me with the blue/ whit tracer. You talking about the "ignition run" line coming off the ignition switch? You have have suffered a shorted alternator field

Run over to MyMopar and download the 71 shop manual. In this case, Plymouth. Also go to the wiring diagrams and download the 2 page aftermarket diagram. This is simpler in some ways than the factory manual and somewhat easier to follow "in some cases" BUT they leave out a lot of detail.

Ignition switch detail from page 382 (8-161) of the 71 Plymouth chassis manual

key.jpg
 
An internally regulated unit should have worked fine IF IT was wired up correctly and IF of course there wasn't some fault in it. "New" (rebuilt) does NOT mean functional.

HOW THE original 70 and later alternator / regulator works. They are simple.

You have the dark blue "ignition run" IGN2 line from the key, which comes through the bulkhead and supplies "switched" underhood loads. That branches off and supplies the ballast resistor (which you likely bypassed) --the alternator field (lite blue) the VR IGN terminal, electric choke if used, and some smog doo dads on some later models.

The blue going to the alternator field is switched 12V to one end of the field magnetic coil. The VR so ;to speak, "controls the amount of ground" through the green wire on the other field terminal. BE SURE the VR is GROUNDED

Simplified diagram of the charging system. Ignore the ignition wiring. Notice that the same wire branches off to ignition, the field terminal, and the VR "I" (ignition) terminal.

Dual_Field_Alternator_Wiring.jpg
 
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jos51700 said:
Step one: stop splicing ****.

Step two: get a diagram, make it match that.
One wire at a time, with the battery disconnected. After each wire, hook up battery, verify no melty smoky sparky sparky.

My guess is, since you're not blowing fuses as you should, is that the wires are melted through and shorted inside the harness somewhere.
Click to expand...
THERE MAY NOT be "fuses to blow." NONE of the ignition "run" circuit is fused
 
Yes, get a factory service manual and start some actual diagnosis instead of simply throwing parts at it.
 
jos51700 said:
I've been in the sun all day. Isn't that what the fusible link does? I can't remember. I'm spent
Click to expand...

The fuse link is not at all dependable and is a high current "last ditch." Here is a marvelous story to illustrate that:

In the early 70's two girls in a Datsun "a holed" my nice 70 440-6 RR. During that time "I got to" drive a POS loaner, a Valiant more door slant. One morning at NAS Miramar, I was to get "off duty" at the RADAR shop, and it was (believe it or not) a fairly cold day, likely near freezing at about 6:30AM. I had started "the loaner" and went into the shop. The leading Chief came in, and he could do an EXACT impression of "Columbo."

Chief Waddell came in, looked at me, "knitted" his eyebrows like Columbo, and says "Mxxxxxxx, I just have one question? Is your car supposed to be SMOKING and making SQUEALING noises?"

So I go out there and shut it off THE ALTERNATOR HAD STOPPED. Bear in mind NAS Miramar, N of San Diego, is 20 miles from McCune Chrysler Plymouth, the POS hacks who were supposed to be fixing my RR. So I got a rag and loosened the belt to see "what."

IT TURNED OUT THAT WHAT was actually wrong, is that one of the diodes had FALLEN OUT of the heat sink INTO the INSIDE of the alternator and STOPPED it rotating, sorta like a wheel chock.

WHEN I WIGGLED THE PULLEY with my rag, I got to sit there AND WATCH the entire underhood harness turn to a melted, welded, smoking, stinking mess, emitting LOTS of smoke, AND THEN AFTER ALL THAT the FUSE LINK BLEW.

I went in and called the dealer, and told them, "your loaner burned up the underhood harness, send out another loaner car and a tow truck. Hours later, here comes the wetback with a beat up pickup full of old batteries and broken down booster cables. I went outside and he looks up and me and says "he man, it's all burned up!!"
 
67Dart273 said:
The fuse link is not at all dependable and is a high current "last ditch." Here is a marvelous story to illustrate that:

In the early 70's two girls in a Datsun "a holed" my nice 70 440-6 RR. During that time "I got to" drive a POS loaner, a Valiant more door slant. One morning at NAS Miramar, I was to get "off duty" at the RADAR shop, and it was (believe it or not) a fairly cold day, likely near freezing at about 6:30AM. I had started "the loaner" and went into the shop. The leading Chief came in, and he could do an EXACT impression of "Columbo."

Chief Waddell came in, looked at me, "knitted" his eyebrows like Columbo, and says "Mxxxxxxx, I just have one question? Is your car supposed to be SMOKING and making SQUEALING noises?"

So I go out there and shut it off THE ALTERNATOR HAD STOPPED. Bear in mind NAS Miramar, N of San Diego, is 20 miles from McCune Chrysler Plymouth, the POS hacks who were supposed to be fixing my RR. So I got a rag and loosened the belt to see "what."

IT TURNED OUT THAT WHAT was actually wrong, is that one of the diodes had FALLEN OUT of the heat sink INTO the INSIDE of the alternator and STOPPED it rotating, sorta like a wheel chock.

WHEN I WIGGLED THE PULLEY with my rag, I got to sit there AND WATCH the entire underhood harness turn to a melted, welded, smoking, stinking mess, emitting LOTS of smoke, AND THEN AFTER ALL THAT the FUSE LINK BLEW.

I went in and called the dealer, and told them, "your loaner burned up the underhood harness, send out another loaner car and a tow truck. Hours later, here comes the wetback with a beat up pickup full of old batteries and broken down booster cables. I went outside and he looks up and me and says "he man, it's all burned up!!"
Click to expand...

So, it is fused.
 
Thank you for the replies thus far. I’m using an original 1971 shop manual and following the diagrams. I have bypassed the ballast for the ign run circuit. I currently have the dash apart and untaped the harness to inspect all wires. Some do have bare spots so I’m taping them up as I see them. A very knowledgeable mechanic and restorer told me to inspect the circuit board for the instrument panel for any damage and I found that the bulb for the ammeter got way too hot (bulb furthest to left) . Boiled the plastic lens (also pictured). Could something as minuscule as a bulb cause a short like this?

779DF78B-A855-4AD2-B98F-97021527385D.jpeg


8B4235B8-FEAB-4E85-B65E-21A00324CBF7.jpeg


357BC391-ED5E-4B16-9BC6-7F22C0FE8249.jpeg
 
It's a dead short somewhere. Indicator? the wires are melting. Put thre right alternator and regulator on and start there, Rick auto has stuff cheap.
 
jos51700 said:
So, it is fused.
Click to expand...
No it is NOT fused I attempted to explain this earlier. The fuse LINK is NOT A FUSE. It is a dangerous, "maybe" "I might blow if I frickin feel like it" and it is VERY VERY high amperage. IF YOU GET A SHORT in an UNFUSED circuit such as the "run" circuit, THAT FUSE LINK WILL NOT BLOW, because the small "run" circuit wiring will melt long before
 
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Three60Demon said:
I found that the bulb for the ammeter got way too hot (bulb furthest to left) . Boiled the plastic lens (also pictured). Could something as minuscule as a bulb cause a short like this?
Click to expand...

That bulb IS fused and with a quite small fuse, the "INST" fuse at one end of the fuse panel, PLUS the illumination lamps are all controlled by the "twist to dim" control on the headlight switch. So, no

Read this article:

Catalog

Whether you bypass the ammeter or not--and there other methods of doing so--this article gives and overview of the what/ how of ammeter circuit failures. Even "Ma" knew this as Chrysler started doing away with the "full current" ammeters in the big boats, and finally in A bodies in either 75 or 76. Also, on the cars WITH "full current" ammeters, Ma did a "partial" bypass of the bulkhead connector on optional 65A equipped cars. This is known as "police fleet taxi" wiring and is likely in your manual for maybe B bodies.

What can happen "right at" the ammeter is that the studs get loose and generate heat and then from there self destruct. Also the wire terminals can fail and do same thing. Likewise, the terminals in the bulkhead connector were NEVER meant for the kind of current they must carry

When you installed the integral regulated alternator, what/ how did you do/ wire up the green and blue field wires off the old one? I'm thinking THAT is the start of the problem
 
DANGER!! Bear in mind those two large ammeter wires ARE BOTH ALWAYS HOT!!! The RED comes direct from the battery through the fuse link, and the BLACK is hot via the ammeter and feeds to the "welded splice" and back out to the alternator

CLUSTER TROUBLES. There are several things you should consider doing now that you have the cluster out

1...Replace the original gauge regulator/ limiter with an RTE
2...Solder jumpers across the limiter socket on the PC board to the traces. Scrape them clean with an exacto, etc
3...The gauge studs typically get corroded. Work the nuts "loose / tight/ loose/ tight" a few times to "scrub" them clean and tighten
4...Check carefully the PC board to harness connector pins. Evidence of looseness, corrosion, you need to clean them up and solder them.
5...As you can see, "corrosion." Clean around all bulb sockets, clean the sockets or replace, and bend the socket contact tabs for better contact. Consider replacing bulbs. Some guys have "gone LED" but there can be complications.
 
what’s the story on them post in the second to last pic posted? looks like they are touching the housing
 
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