First startup attempt, Melted wire....Help!

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JeffreyLee

JeffreyLee

1965 Barracuda
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  1. 318 LA engine, new electronic ignition system, alternator, coil, plugs, wires, also a completely new under hood wiring harness intended for use with a electronic ignition...Turned the key and started the car for the first time in over 2 years. After priming the carb a little, engine started to run! Victory! My satisfaction was short lived. Once the engine started to run on its own, I started to see some smoke from the battery area. The secondary power wire from the battery started to melt from the battery post backwards towards the firewall. Luckily, I was able to quickly pull off the terminal and prevent any really significant visible damage. Only a couple of inches of insulation was melted away from the wire. I also noticed from the corner of my eye, when the car was starting, I thought that I saw some sort of spark coming from the general vicinity of the new alternator. I am using a new alternator with a 2 wire connection and the external voltage regulator. The electronic ignition system has 2 small wires for the alternator as well as the primary feed, blue and green. I used the blue wire, wrapped up the green. I am pretty sure my wiring to the bulkhead is correct. My thought is that I might have plugged in my ballast resistor backwards. I understand that there is a "run" and "start" position. There are 2 wires going into each side of the ballast resistor with a connector that could be installed opposite of what I have done. Is this a likely issue or can anyone give me some thoughts about tracking down my problem. I have included some images of the bulkhead wiring, ballast resistor and battery. Thanks in advance, I'm getting close here!
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  2. Yesterday at 12:09 PM#2
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    missing lincLoose nut behind the wheelFABO Gold Member

    I would suspect a dead short somewhere, possibly the wire is pinched and grounding out.
  3. Yesterday at 12:12 PM#3
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    missing lincLoose nut behind the wheelFABO Gold Member

    Been a while, but IIRC that wire supplies the "accessory "power.
    Best to get a wiring diagram and work through that.

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  4. Today at 8:49 AM#4
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    MrJLRBuilt, not boughtFABO Gold Member
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    I hate problems like that .....hope the OP has a quick "aw haw!" moment!

    Jeff



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  8. 24 minutes ago#5
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    oldkimmerFABO Gold MemberFABO Gold Member

    NewI would move /replace ur rubber fuel hose. A fire waiting to happen. Kim

  9. 22 minutes ago#6
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    JeffreyLee1965 BarracudaFABO Gold Member
    No Quick Aw-Haw...unfortunately..There is obviously a problem with the accessory feed to the starter solenoid somewhere. I disconnected all of the interior fuses in order to isolate the short. There are only a few wires going into the solenoid..... Accessory feed from the battery, jumper from the accessory feed post to the bulkhead connector (to provide power for interior), the violet wire that feeds the horn relay. There is the feed to the neutral safety switch and the yellow wire going to the bulkhead connector which I think is the solenoid trigger from the ignition. I got out my test light, rigged up a 30amp fuse in line from the battery and started poking around. Only my accessory power is hooked up, not the main power lead to the starter. Here are my observations: When I hook the test light ground to the battery, I have power at both the main feed post AND the single wire leading to the starter solenoid. When I touch the test light to the yellow wire, I hear the solenoid "click". My thought is that there shouldn't be power at the starter solenoid feed until the key is turned on and "bridges" power to the starter. The minute I connect the battery's negative post to the vehicle ground...POP, goes the fuse! The problem with the electrical diagrams I have is that the 1965 version doesn't have electronic ignition. I also have a diagram from a 72' Plymouth that uses electronic ignition. I have been able to plow through this restoration with the help of my FABO friends so far. Please give me some insight. Thanks
 
I don’t think the ballast resistor is your issue. From your pictures you have the keyed plugs, so they only go one one way. Is you are seeing some smoke from the alternator, I would take it to a parts store and have it tested.
 
Ok, just reread your post. The voltage regulator you are using requires both wires to be connected to the alternator. If I read your post correctly, you did not use the green wire?
 
A ballast resistor is a path, not a load. Direction of flow does not matter for the ballast resistor. You have a short or very high load somewhere - that's what melts insulation. As others said, the green wire must be connected to the alt, but that did not cause the melted wire, unless the wire grounded and the alternator went to "full field" for a long time.
 
On the starter relay you have 3 wires, red, violet and a second red wire going inside the car, if you wiring harness is original. Disconnect the red wire going inside the car. These goes to the amp gauge and then to the alt. See if that stops the large draw or short. Try this first, if not you'll have to look at the wire going to the solenoid.

You can also get free wiring diagrams from My Mopar.
 
I have A bodys If you are running a higher amp Alt you have to up grade you feed wire.. also check you amp gauge that is a straight feed to you bat from charging system and seen alot of them melt down from gauge
 
Mike69cuda said:
Ok, just reread your post. The voltage regulator you are using requires both wires to be connected to the alternator. If I read your post correctly, you did not use the green wire?
Click to expand...
thats right Mike, the alternator only has 2 connecting points. In reading the directions for the electronic distributor it refers to the "green wire not used"
 
...is the power wire running to the starter solenoid (on the starter) supposed to show power anytime the accessory wire from the battery is connected to the firewall solenoid? My thinking is that the solenoid power wire should be lit up only when the ignition is turned to start, which bridges power to the starter solenoid. Is that incorrect? Once again, I can ground my test light to the negative side of the battery and probe for power with no problem. The second I touch the negative battery cable to the battery...Poof! another fuse blows.
 
JeffreyLee said:
thats right Mike, the alternator only has 2 connecting points. In reading the directions for the electronic distributor it refers to the "green wire not used"
Click to expand...

The alternator and the electronic ignition wiring are not really related. That is a little confusing.

There are two different kinds of alternators, Three wire and two wire. The regulator you are using requires a three wire alternator. That is the regulator above the can of starting fluid, correct? Orange sticker on it?

How many connection points are there on your alternator? If there are three, the green wire should go to the empty one. If not, you have the wrong alternator. Post a picture of the back of it.

The alternator may not be your problem, but in troubleshooting if you see something fishy, that is usually a good place to start.
 
I have another idea. I have been pouring over my wiring diagrams and it is not perfectly clear which wire should feed power to the interior. My new wiring harness has a large black wire with a forked connector, my old harness had a short jumper from the starter solenoid to the second large connector on the bulkhead. Is it possible that I got the 2 of these primary wires reversed? I have included a picture with the top part of my connector removed for clarity. The wire with the blue insulator is currently hooked up to the bulkhead stud closest to the fender, which was attached to the power stud on the starter solenoid.
 
By the way......Thanks to everyone who called out that fuel line routing issue! That could have been a really big, stupid problem.....
 
You did the right thing by disconnecting the power. That's the best way to stop an electrical fire or prevent one from developing in that situation.
JeffreyLee said:
and it is not perfectly clear which wire should feed power to the interior.
Click to expand...
There are two power feeds because there two power sources.
Alternator and Battery
This is the trick to understanding the main circuit.
Current flows from whichever one has the highest voltage.
(Its like if your house had a well pump that could supply 20 gal/min of water at 15 psi and a storage tank with 500 gallons, but at 12 psi.)

The battery and alternator are connected together at a welded splice under the dash.
We can think of this splice as the primary power distribution point because from here, power can go to the other main circuits.
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After the car is started, if everything is working correctly, the alternator will supply power to the ignition and recharge the battery.
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The battery should draw 5 to 10 amps for a short while, and then less and less current. When its recharged it will draw zero even when available at 14 volts or so.

One of these two should be the alternator output and the other should be the battery output/recharge wire.
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If you noticed which way the ammeter went after start, that will be a clue as to the wire melting.
Only a clue because we don't quite know how your new harness is different than stock...
 
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Since it has a wiring for a two ballast ECU and the ground controling voltage regulator, the critical circuits should be like a '73.
The coil wire should be to from th e 1/2 Ohm resistor and the ECU from the 5 ohm. Newer ECUs don't need the 5 ohm resistor but simpler just to have it all wired since you have it.
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It may be impossible to answer your question because the wiring MAY NOT BE factory colors. Example, why is there a blue connected to the starter relay?

A fried wire that large ALWAYS indicates a bad short.

HOW TO CHECK FOR SHORTS without burning up more "stuff."
Get yourself some large wattage 12V lamps as well as a smaller test lamp, test LAMP, not an LED

Disconnect the battery ground, and wire a BIG 12V lamp in series with the ground wire to the battery. The lamp will light if there is a big short. A headlamp works well. For "a smaller" load, use an old tail lamp socket with a 12V stop and tail lamp in. Go around pulling fuses and disconnecting until the lamp goes dark.

ALSO do not forget to disconnect such things as the alternator to check for shorts. The alternater may example, have a shorted diode.
 
Thanks all you guys, I have un-hinged the dash and rotated it down so I can get a good look at the underdash wiring. Once again, all of the wiring underneath, fusebox and pigtail going to the rear lights are all new....Plus the Dali Lama said I will achieve perfect consciousness before I die....So I've got that going for me. I really appreciate all the diagrams and explanations. I'll get a fresh outlook and start probing in the morning.
 
First things first, I disconnected the power wire feeding the interior (pictured) hooked up the main battery lead and ground as well as the accessory feed...No smoked fuse. Problem must be inside. In thinking things over, when I first connected the battery in my original way, there was no melted wire or apparent short. Headlights worked, front parking lights worked, rear side interior lights and tail lights worked. None of my turn signals or dash lights or radio lit up. Problem began when I first tried starting the car, that's when all hell broke loose. These may be clues to tracking down the problem... BTW, I will go to the auto parts store and get a new, 3 wire alternator. It is obvious from these posts that it is needed. Thanks
 
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