Poll. Mopar bulkhead connector issues. Please read if you have not upgraded

[redgum78]

Hi everyone.
I thought would try and raise awareness of bulkhead/firewall electrical connector issues on our classic Mopars.
Many of you will be fully aware of this issue but I am sure there are plenty of people out there that are not.
If you are aware of this issue please feel free to add you comments and to vote. If raising awareness about this issue saves a single electrical fire on a classic Mopar then it was well worth it!

There are a couple of problems with the bulkhead connectors as I see it.
1-They don't seal very well which allows moisture and eventually corrosion to form on the terminals.
2-They don't handle high load applications very well.

The main problem you are likely to encounter is on the alternator charging circuit. It is really the only circuit on the bulkhead that carries any decent amount of current. It is routed from the alternator to the amp gauge in the instrument cluster then to the positive on the battery. To get to the amp gauge and back to the battery all the charging current passes through 2 connectors on the bulkhead. If you have any corrosion on these connections or if you have increased the capacity of your alternator you are at real risk of burning out these connections.
If this happens the BEST case scenario is your battery stops charging and hopefully holds enough charge to get you home.
The WORST case scenario is an electrical fire and a complete re-wire if you managed to get the fire out before your car burns to the ground!

There are several fixes available depending on what you need. If you don't need accuracy on the Amp gauge and aren't worried about maintaining original wiring the easiest fix is an additional wire to help carry the load. If this is not suitable there are other fixes but they get a little more complicated and can be discussed (or Googled) later in the post.

I had a quick search......hopefully I haven't doubled up on an existing post.

[Pete in NH]

One of the major factors in discussing the issue of the bulk head high current pins is that age and time takes its toll. Chrysler never designed this system with the thought they would be on the road 40 + years later. This is where the corrosion factor comes in.

When these systems were new they worked as designed even though they were a bit marginal on wire size and the current capacity of the pins. Chrysler did know they were marginal even with the stock size alternators but in practice millions of cars were on the road with this wiring and they did not routinely burn up.

B body cars that were used as police cars and taxi's and carried radios of the day which required lots of power to operate used special 60 amp alternators and a wiring modification called " Fleet Wiring" which used heavier wiring and bypassed the bulk head connector pins. Wiring was run directly to the ammeter terminals through a grommeted hole I the firewall. If you carefully study shop manuals of the day you will see reference to this modification. It can be easily done on cars today and is well worth doing.

[Charger RT]

On my 68 both terminals going through the firewall were in decent condition. I do have a 60 amp alternator on the car but to preserve these connections I ran a wire from my alternator back to my battery to stop the current that ends up at the battery from going through the fire wall twice. It now also means the two wires running through the bulk head connector share the load of all power used inside the car since that is all they do now. My car has no added loads inside the car other then an old school fm converter hidden in the glove box. The amp meter does not work because of my added wire but that is fine by me. I would love to replace it with a volt meter that matches the other gauges. I think there is a thread on that. To keep my factory look the wire I added from the alternator I did a black wire and tried to hide it while running it on the bottom side of the factory harness back to the battery.
Tim

[redgum78]

I have done the fleet modification on my Charger as I liked the idea of the gauge still working. If I was running additional equipment I would be doing the bypass like Charger RT has done for all the reasons he mentions. In my opinion it is the easiest and most reliable fix with the lack of an accurate gauge been the only real down side.
On a side note...does anyone out there own a Mopar that has factory fleet modified wiring? Is there a option code of it?

[myk]

Went with the EZ wiring kit and took out the bulkhead connectors altogether.  In retrospect, I wish I had kept something like the  bulkhead connectors; it's going to be tough working on a wiring harness that is connected directly to the accessory and the fuse box with no break in between.  It's reliable, though!

[mopar0166]

Yeha I don't even use my bulkhead connector any more, it just there as a visual, the wires just pass right through it.  it wasn't a priority for me to replace it to have allthose connections

[Kern Dog]

"There are a couple of problems with the bulkhead connectors as I see it.
1-They don't seal very well which allows moisture and eventually corrosion to form on the terminals.
2-They don't handle high load applications very well."


Yeah, they are a terrible design. They only lasted 47 years. What a piece of shit.   

Remember, these cars were never built with the expectation that they'd still be used 47 years later. The sealed quite well when new and for several years after the body rusted away or the engine wore out. They handled the loads that the factory placed on them. AM radios, incandescent lamp bulbs.....NOT alarm systems, High energy ignitions, electric fuel pumps, electric fans or auxillary guage sets. The cars were built to meet minimum standards and they were fine for several years in stock form.
I do agree though that after several years, improvements and upgrades are necessary.

[redgum78]

Yeah, they are a terrible design. They only lasted 47 years. What a piece of shit.   

LOL only 47 years!
I agree the wiring and connectors did the job back in the day. I am not bagging out factory practises from 40 plus years ago. More interested in making people aware that owners are likely to have an issue sooner or later if they are still running the original plug without mods.

[Nacho-RT74]

Many of you know what I have done with my upgrade post. Have serviced the bulkhead thought and ammeter is still on line

[Nacho-RT74]

One of the problem here is lot of ppl underestimate the electrical section while everything take cares of performance upgrades... Gas line, steering, suspension, drivetrain etc.. But take a side to the electricity

[1973rallye]

I have followed Nacho's lead on this one. Everything is working better than ever.

[Nacho-RT74]

need to note, the bulkhead upgrade ( mantenience and bypass or parallel on charging wires ) is a help for bulkhead weakness, but still needs a good alt to keep ammeter safe and not bouncing... some one able to feed in between 48-55 amps iddling when required.

Bouncing amm needle means load going through... load going though means heat... then...

[crj1968]

Hey Nacho- could you send me the link to your bulkhead upgrade post?

Search function does not work for me- thanks!

[rebby]

Hey Nacho- could you send me the link to your bulkhead upgrade post?

Search function does not work for me- thanks!

You're probably looking for this thread.

[crj1968]

Hey Nacho- could you send me the link to your bulkhead upgrade post?

Search function does not work for me- thanks!

You're probably looking for this thread.

Thanks Rebby- thanks Nacho !

[Nacho-RT74]

Sorry, haven't being on line latelly for long time

http://www.dodgecharger.com/forum/index.php/topic,33574.0/all.html

link to ALL thread instead going on pages

Note, I make parallel wiring because existing alt and batt wires of donor harnesses I got ( I rebuilt my engine bay harnesses ) were still in good conditions, but if your one are toast ( terminals or cavities, or both ) you can rid off completelly the existant charging wires on engine bay side, and run new ones through firewall.

you can cut and seal wires on cab side at bulkhead end, but keep the existant ones on ammeter studs. make mantenience on those ends