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bulk head connectors

bearman

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what's the fix. after market have the same problem and is it from old age or a factory screw up. what's everybody fix i'm sure this has been address before i'm curious as everybody ups the alt and adds electronic everything but never them talk about changing the bulk head when they do this. everybody changes from ammeter to volt meter but uses the bulk head connector. which is a real problem to begin with. so curious of the fix to the bulk head problem
 
I ran wiring directly through the firewall. The bulkhead spade connectors are not suited for higher currents if upgrading the charging system. They tend to overheat, corrode and become loose fitting, which I do not trust for the heavier power wiring.
 
I ran wiring directly through the firewall. The bulkhead spade connectors are not suited for higher currents if upgrading the charging system. They tend to overheat, corrode and become loose fitting, which I do not trust for the heavier power wiring.
I'm getting ready to go that direction myself. The mad electrical suggestion of drilling out the bulk head connector and passing the wire through there bugs me for some reason. I'm also considering changing from fusible link to some sort of fuse holder on that connection.
 
Not everyone blindly follows the full “Mad Electrical” approach. Read that article carefully, specifically states it addresses the late seventies Dodge truck plastic ammeters. The earlier passenger car ammeters don’t spontaneously combust. Start with by-passing the bulkhead connectors in the charging circuit. Add a hole in the firewall with a good grommet, run the wires directly to the ammeter.
Inspect the ammeter connections for previous over-tightening and/or insulator damage.



If the larger alternator and additional loads are added the vehicle, up-size the charging circuit wiring and fusible link.


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Chased an electrical problem for 3 years. Driving along, car shuts off like someone reached over and pulled out the keys and threw them out the window. Once on top of Carson Pass. Didn’t happen again for 18 months. Replaced ignition etc in the meantime. Quit near the house one day, coasted to the curb. Had an electric fuel pump at the time. Left the ignition in the on position, went under the hood and started pulling on things. Son of a bitch if I didn’t grab the bulkhead and the fuel pump started running. 3 ******* years. Got home and ordered every component, plug, receiver. It’s all still on the shelf in the closet. I carefully removed each plug bank without breaking the ears off and sprayed them with electrical contact cleaner until the black ran clear. Looked like they had not been touched since the boys installed them on Lynch Road. I used the whole goddamed can. I plugged them back in and it has worked perfectly since. It’s been a few years now. An aha moment after years of terror never knowing when or where this would happen again. I will leave a sleeping dog lie. If it takes another 45 years, I won’t be here to worry about it. Ammeter disconnected.
 
just can't see using that type of connector with all the better types being out there to use.
 
just can't see using that type of connector with all the better types being out there to use.
No vehicles built in that era were ever designed to last more than 5 years or so, until the next trade-in. The Packard 56 terminal was fairly standard in the automotive industry of the time. Never designed to handle more than a few amps of current, but made for quick assembly line connections. Exposed to moisture they corroded and built up resistance pretty quick. Using them on a circuit with more than a few amps was a problem and the factory came to know it early on. There were several C-body (more factory loads) recalls to address this issue back in the day. Car manufactures finally came around to sealing almost every electrical connection from moisture.
 
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Back in 1982 I was sitting at a red light idling in my 69 Coronet. It was late at night and dark. I had been smelling something electrical, but could not figure it out until I looked down and saw a dim glow shining on the floorboard at that red light. I pulled into a gas station, looked under the dash, and my ammeter was glowing white hot! Shut the car off and called my dad. He said limp it home without any accessories on and keep the headlights off whenever possible.
The next morning when I got up dad had already been to NAPA and bought a under dash ammeter, and we drilled a hole in the firewall and did our own direct harness rig up. Lasted another 9 years until I sold the car.
I'm not saying ammeters are bad, but from my experience I prefer to run a voltmeter and bypass the bulkhead. I know there are many of you out there that prefer the ammeter and never had an issue, but I'll not do it after seeing mine glow white hot that night many years ago.
 
On that dash cluster, the ammeter is within the cluster frame and would not be visible from under the dash. The connections are visible however, likely what you saw, sounds like you experienced heat build up at the ammeter stud connections. The stud nuts were either too loose, allowing resistance to build and create heat or the fiber insulator failed likely due to over a tightening of the stud nuts, crushing the fiber insulator. Once the fiber insulator is crushed it will no longer maintain it thickness and will lead to the connections loosening up over time. Loose enough, stud contact to the cluster frame is possible and will cause arcing and heat if not a full dead short.
 
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To chime in..I went with all new Autometer gauges and new wires throughout the entire car. I completely did away with the bulkhead connector and fabricated a cover and went straight though that and directly to the location. Lots of work and expensive considering new wires, new alternator, new gauges and everything in between to make the connections! Also, not original which many want to keep, but my car isn’t original anyway so it wasn’t a big deal to me. But, no bulkhead or ammeter to be concerned about.

Good luck!
 
I'm getting ready to go that direction myself. The mad electrical suggestion of drilling out the bulk head connector and passing the wire through there bugs me for some reason. I'm also considering changing from fusible link to some sort of fuse holder on that connection.

That's exactly what I did on mine. If you do it, leave a couple feet of extra wire zip tied together in case you have to take it apart. I much prefer the single wire with no sketchy connections carrying power.
 
Yep was just looking at something similar but bigger (which I thought was over kill). That right there is about perfect, thanks!
 
I had a knowledgeable fellow member give me direction on bypassing the BH for re-wiring up the amp gauge. The gauge is currently bypassed and nonfunctional. So far I've run the new wiring but have left it disconnected for a winter project. My BH shows signs of having been overheated and read up on how amp gauges were a hazardous arrangement. Could be when I installed electronic system some years ago this contributed to this issue...not sure. Recently I had a no start problem - car would only run with key in start mode. The fixes for this are common such as a bad ballast or key switch; but wasn't the problem. After long searching come to find the damn upper harness on the BH was just cocked loose enough losing contact...tip it up and car runs fine. Old BH, and as mentioned, car mfg's don't make them to last half a century. Some day I might look to replace the in cab wiring as I have a new engine and rear harness done so far.
 
Grab that goddam connector, torque on it, then spray the **** out of it with electrical contact cleaner. Good as new.
 
Finally getting around to this, went with Dipsticks suggestion. Under the dash the ammeter is bypassed and both wires are brought to the post. On the firewall, 16ga fusible link from starter relay to post. Added 14ga fusible link to alternator wire and bright it to starter relay as well.

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For what’s its worth my 72 Charger had the entire harness burn up from the electrical problems highlighted in the Mad Electrical article. It wasn’t just trucks.
 
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