Bulkhead Connector replacement tips/advice

Swanky

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bulkhead.jpg

66 300 is bricked due to a typically fried bulkhead connector. I have ordered a replacement.


Before I start this job, I want some info please.

1) I have read people say this must be done inside the car, under the dash, and others say you can pull it into the engine compartment and do it that way. Anyone know for sure what the answer is for my car?

2) Various people said they did this switch in an hour, which gives me great hope. Is that realistic?

3) I don't know what the back side of this looks like. Is there a wire connector for each "slot" and I pull the wires from the old and put them in the new, being careful to put them in the right spots? Should I do anything as I do this like spray with contact cleaner, etc.?

4) The plugs on the engine side are not melted and I intend to put them back. Cleaning them out of course, but I have read folks talk about sanding the connector prongs first. Should I be doing that?

5) I read about dielectric grease, but not sure what to do. I thought it was conductive, but it is not. I know it prevents corrosion, but I assume the entire prong needs to contact the female as well as possible and that grease would impede that. What do I do with dielectric grease here. Everything says apply is lightly, but do I bother?

6) I worry, from other posts, that the plugs may be loose after I pried them off and maybe the plastic side tabs will be loose. Any way to tighten them back up? Replacing those plugs looks like a whole world of work I have no idea how to do.

Thanks!
-Tim
 
1) I have read people say this must be done inside the car, under the dash, and others say you can pull it into the engine compartment and do it that way. Anyone know for sure what the answer is for my car?
I'd do it from under the dash. Take the front seats out and it gets a zillion times easier.
2) Various people said they did this switch in an hour, which gives me great hope. Is that realistic?
Depends on how fast you work, and what issues you run into.
3) I don't know what the back side of this looks like. Is there a wire connector for each "slot" and I pull the wires from the old and put them in the new, being careful to put them in the right spots? Should I do anything as I do this like spray with contact cleaner, etc.?
Yes, they have a female spade connector in each slot. The connector has a little tab that holds it in place that you will have to bend down. I use a small screwdriver or something similar. See the little bent thing on this connector? That needs to be bent down and then bent back up when you reinsert it.
1726522845615.png

4) The plugs on the engine side are not melted and I intend to put them back. Cleaning them out of course, but I have read folks talk about sanding the connector prongs first. Should I be doing that?
I don't like to sand them as it removes the plating. I like to use this stuff to clean them up. Amazon.com
5) I read about dielectric grease, but not sure what to do. I thought it was conductive, but it is not. I know it prevents corrosion, but I assume the entire prong needs to contact the female as well as possible and that grease would impede that. What do I do with dielectric grease here. Everything says apply is lightly, but do I bother?
You are correct that it is non-conductive. I don't use it much or really see a use for it in a limited use car. If you do use it, smear it around the outside of the insulator and not on the connector itself.

It's one of those things that a little is good, so people incorrectly figure that you should use it by the drum load.
6) I worry, from other posts, that the plugs may be loose after I pried them off and maybe the plastic side tabs will be loose. Any way to tighten them back up? Replacing those plugs looks like a whole world of work I have no idea how to do.
Not much more work to replace than what you are already doing. It might even be easier because you aren't under the dash. Again, a little tab holds the connector in place and will need to be bent down.
 
Some of it depends on the free length of your wire harness in the car. However I think you will find that the burnt one (likely to the ammeter) will be stiff and the insulation melted. You will likely have to replace a good chunk of those wires from inside the car. I needed to on mine.
 
couple of things...pushing down on the 2 spring clips up top will allow the connector to tilt into the passenger compartment and lift off the lower clips...at that point you may be able to twist it diagonally and pull it back into the engine compartment...depends on how much slack there is in the harness....each female spade connector in the plug has a little tab on it that locks it into the bulkhead connector...you need to slide a thin flat tool in from the engine side in the slot below the spade...that will release the tab and allow you to pull each wire out the back...once you see its condition you can determine whether you can clean it up, possibly squeeze it tighter if it is loose, or crimp on a new one...the male ends that are in the engine side plugs can be squeezed on the sides with needle nose pliers to release them from the plug, they will be easier to clean up if they are out... the melted ones may do exactly the same thing again...the connectors for the 2 large wires were barely adequate when they were new, and age and corrosion build up resistance and make connections hot...many people will just run a new wire straight through the bulkhead plug and eliminate those 2 connectors completely...others go even further and upgrade wire sizes and/or bypass the ammeter ...lots of threads here on doing that
 
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I'd do it from under the dash. Take the front seats out and it gets a zillion times easier.

Depends on how fast you work, and what issues you run into.

Yes, they have a female spade connector in each slot. The connector has a little tab that holds it in place that you will have to bend down. I use a small screwdriver or something similar. See the little bent thing on this connector? That needs to be bent down and then bent back up when you reinsert it.
View attachment 682243

I don't like to sand them as it removes the plating. I like to use this stuff to clean them up. Amazon.com

You are correct that it is non-conductive. I don't use it much or really see a use for it in a limited use car. If you do use it, smear it around the outside of the insulator and not on the connector itself.

It's one of those things that a little is good, so people incorrectly figure that you should use it by the drum load.

Not much more work to replace than what you are already doing. It might even be easier because you aren't under the dash. Again, a little tab holds the connector in place and will need to be bent down.
Would all of this be the same on a '70? (I've been having BC issues for over three years.)
 
Would all of this be the same on a '70? (I've been having BC issues for over three years.)
Yes. It's a slightly different connector with the fuse block clipped to it, but otherwise the same.

In a '70 up car, the one wire that I always suggest looking at is the red wire going into the connector under the steering column. Usually there's burn marks in the white insulator where the connector is failing. A piece of wire can easily be spliced in to bypass that connector. All the rest of the wires (turn signals etc.) can be left as they are.
 
Some of it depends on the free length of your wire harness in the car. However I think you will find that the burnt one (likely to the ammeter) will be stiff and the insulation melted. You will likely have to replace a good chunk of those wires from inside the car. I needed to on mine.

Replace the wires, or cut off the end and put a new end on it?
What tool do I need to put new ends on the wires, and where do I get those female ends?

If I have to replace the wire, that means what, find where it goes and what gauge (in the shop manual) and make a new wire with both ends and put it back in place? Sounds like this may take a while.

I imagine the melted connection to the battery is going to need to have a new female end on it for sure.

-Tim
 
I'd do it from under the dash. Take the front seats out and it gets a zillion times easier.

Depends on how fast you work, and what issues you run into.

Yes, they have a female spade connector in each slot. The connector has a little tab that holds it in place that you will have to bend down. I use a small screwdriver or something similar. See the little bent thing on this connector? That needs to be bent down and then bent back up when you reinsert it.
View attachment 682243

I don't like to sand them as it removes the plating. I like to use this stuff to clean them up. Amazon.com

You are correct that it is non-conductive. I don't use it much or really see a use for it in a limited use car. If you do use it, smear it around the outside of the insulator and not on the connector itself.

It's one of those things that a little is good, so people incorrectly figure that you should use it by the drum load.

Not much more work to replace than what you are already doing. It might even be easier because you aren't under the dash. Again, a little tab holds the connector in place and will need to be bent down.
Thanks for all this info.

A few more questions. I want to be as prepared as possible before I start.

Where do I get the female and male ends, and what tool to crimp them on? Also, wires, if I need to go that far.

It is a convertible and I don't have the shop manual add-on for that. I am wondering if the top motor goes through that battery connector that's melted or if the top motor has it's own connection.

I read this thread on the ammeter bypass and plan to do that along with this job: Underhood Ammeter Bypass

I never want this to happen again, is that wire going to help prevent this problem?

I bought the car a couple of moths ago and the top was destroyed in transport. Drove it a few times around the block waiting to get it fixed and topped off the gas. Got it back after 3 weeks from the shop and put the top down and drove it and this happened. I am so stressed that my car is a dead brick! I can get all sorts of issues fixed by any number of local shops, but they won't fix this. I am so lucky it died with the top up in the garage! I am in knots and loosing sleep. Buying new tools and planning. A bit terrified of this happening on the road. Losing power in traffic sounds like a catastrophe. I think maybe this is related to the top motor and revving the engine to get juice to put the top up and down, and maybe on the road the car is mostly not pulling a load off the battery and maybe it is less likely while driving?

Thanks for the insights.
 
I replaced the contacts in my bulkhead connector and the cable connectors a month or two ago. I got a set of these contacts off ebay (male and female). These are also called packard connectors I guess.

I made a diagram of the connectors, with labels using numbers, I printed the labels on some sticky-back paper. I popped the bulkhead connector out into the engine compartment. Now, here's where you probably don't want to do that. I was replacing my front stub frame, so I had no frame, no engine, no fenders in the way. If I had to do this on an intact car, I would do this from the inside. There is practically no extra slack to work with these wires if you pull them forward into the engine compartment.

Ok, so what I did next was to wrap a label on a wire, then cut the wire right at the connector. This is the bulkhead connector I'm talking about. So all the wires are cut, but they all have labels a couple inches back from the cut ends.

Next, I stripped maybe 3/8 inch of insulation off the ends. The use of a wire stripper is highly recommended. I have one like this:

1726704098068.jpeg



I've frequently stripped old copper wire and the strands were black or tarnished and a pain to clean up, but I was surprised that these wires were clean. Next I crimped the new connectors onto them and for good measure I applied solder to the crimp. Then it was just a matter of inserting them back into the plastic bulkhead connector. I did the same thing with the mating plugs, but they get a spade connector.

I think the direction that the contacts are inserted should be observed, and match how the originals went in.

I found that it took quite a bit of force to plug them in, I took an icepick and adjusted some of them to make them easier to insert.

Here's a pick of what my original connectors looked like (these are in the cable plugs). One of them had a repair done to it.


530.jpg


After everything was back together, I connected a 12 volt car battery charger to the system in place of an actual car battery. I didn't want to fry anything in case I messed up the wiring. The charger has enough power for lights and stuff but can't fry anything. I checked for 12 volts at the ballast resistor and coil, at the starter solenoid, horn, etc.
 
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Yes. It's a slightly different connector with the fuse block clipped to it, but otherwise the same.

In a '70 up car, the one wire that I always suggest looking at is the red wire going into the connector under the steering column. Usually there's burn marks in the white insulator where the connector is failing. A piece of wire can easily be spliced in to bypass that connector. All the rest of the wires (turn signals etc.) can be left as they are.
Thanks. I'm out of town for five days, but I'll look when I get back.
 
Thanks for all this info.

A few more questions. I want to be as prepared as possible before I start.

Where do I get the female and male ends, and what tool to crimp them on? Also, wires, if I need to go that far.

It is a convertible and I don't have the shop manual add-on for that. I am wondering if the top motor goes through that battery connector that's melted or if the top motor has it's own connection.

I read this thread on the ammeter bypass and plan to do that along with this job: Underhood Ammeter Bypass

I never want this to happen again, is that wire going to help prevent this problem?

I bought the car a couple of moths ago and the top was destroyed in transport. Drove it a few times around the block waiting to get it fixed and topped off the gas. Got it back after 3 weeks from the shop and put the top down and drove it and this happened. I am so stressed that my car is a dead brick! I can get all sorts of issues fixed by any number of local shops, but they won't fix this. I am so lucky it died with the top up in the garage! I am in knots and loosing sleep. Buying new tools and planning. A bit terrified of this happening on the road. Losing power in traffic sounds like a catastrophe. I think maybe this is related to the top motor and revving the engine to get juice to put the top up and down, and maybe on the road the car is mostly not pulling a load off the battery and maybe it is less likely while driving?

Thanks for the insights.
Stop, you didn't cause this. The car is 56 years old.
This isn't nearly as challenging as it may seem. Take pictures with your phone for reference.
Once you have the terminals or if the connector spray electrical cleaner and a tooth brush. Replace any ends that need replaced and put them back in the connector. Before assembling the two halves together or de oxit on each connect to prevent future corrosion.
 
Where do I get the female and male ends, and what tool to crimp them on? Also, wires, if I need to go that far.
You can buy in bulk at Amazon or the better bet might be to buy a set from eBay like these. https://www.ebay.com/itm/125639605048?_skw=mopar+wire+terminal&itmmeta=01J8926E0JSVKP5K05BSMEMS4Z&hash=item1d40b43b38:g:aSoAAOSwg61mE2BH&itmprp=enc:AQAJAAAA8HoV3kP08IDx+KZ9MfhVJKnN8HrN6aI8iXyTQPx59SvqZ5hA1sMKboIIBrkeVkucd0SSlEsIECxR/xiHogY/VV5vPeMGtHUTUUBrfQ/zkyL0kkBrHWwY66NrOAzZqjj2cMGxjr0Z5OrajAPKPjOe4Vp9f1i1UZt8JLkCwbSAEQaJUz0OXs0SfcGuYCddK9EvyjdXTbiR9cS6y6Nmou4ZmTxUaQ8h919PhZKZ+6SYSjCL06drNrd1VhabZp0KXV13qOZNnhq--h2s5yPuphDCaZy7ajBWNY5Uu0wuzDYR0HcN3E+Nvi7GKpkzlbM88/H8WQ==|tkp:BFBMvuCZosJk
You'll need a crimper and it has to be for an open barrel terminal. I have these. Amazon.com
I use this stripper as I've found it doesn't nick the wire like others might do. Amazon.com

If you buy wire, be sure to buy "automotive primary" wire. Local parts stores, Amazon etc. You don't want to use solid wire or stranded wire for home use.
It is a convertible and I don't have the shop manual add-on for that. I am wondering if the top motor goes through that battery connector that's melted or if the top motor has it's own connection.
No "add-on" for the shop manual. That's assuming you are using the factory manual. Download one here if you don't. Service Manuals – MyMopar
I read this thread on the ammeter bypass and plan to do that along with this job: Underhood Ammeter Bypass
There's some discussion about this going on. My opinion has waffled back and forth, but I'm believing it not being necessary most of the time. I'm not going to suggest one way or another.
 
This is what I bought:


It's a set of 8, you'll need 3 of these sets to fill in all contact positions. I think there will be differences in construction between these various items sold on ebay.
 
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