Intermittent total loss of electrical

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Your photo shows correct wiring for a '67.

The fusible link is in the bulkhead connector.
Maybe to see in this photo.
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Original
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Maybe in this process the link was eliminated. When you have a photo we can see how it was done.
When the factory ran wires to the ammeter through a grommet instead of using the multi-connector they had a couple different ways of handling the fusible link(s).


I agree, but the ignition switches do get worn out internally. I'm just replacing the one on my '67 now but its been on its way out for years. The car has at least 250,000 miles on it so not terribly surprised...
When I check the internal positions for resistance, run had as much 300 ohms depending on how I wiggled the key...

I agree.
There's two reasons it might be charging at a higher rate. The first simply is the battery is a little more discharged. The second is that increased resistance to the current makes the voltage regulator sees a lower voltage. When the regulator sees lower voltage, all it knows it is to increase the field current. So if the alternator is producing power now at say 15 Volts when before lets say it was 14.5 Volts, the battery will charge at a higher rate.
OK. Three reasons. if the there is a better connection now between the alternator and the battery, less resistance = high voltage seen be battery = draw more current for charging.
Thanks. Based on all of the above, it would appear the fusible link was cut out and replaced with a soldered wire that runs through the port (not pins) of the bulkhead connector to the ammeter. The first pic is as found, the second pic after I removed the tape.
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and a solid wire run through the port.
Its possible the splice or terminal crimps that person made are now coming loose. Or even the nut holding the ring terminal, especially if the wire was under some strain that made it want to rotate counter clockwise. None of these high probability but all certainly possible.
Looking at how the splice was done in the engine compartment might give an idea of the quality of the work that's under the dash.

When Chrysler bypassed the multiconnector, usually the fusible link was moved to the starter relay. Sometimes a second link was added depending on how the size of the wires and whether the ammeter was also used as a distribution point. Unfortunately maybe the person who did the modification did not consider the link important.
 
Its possible the splice or terminal crimps that person made are now coming loose. Or even the nut holding the ring terminal, especially if the wire was under some strain that made it want to rotate counter clockwise. None of these high probability but all certainly possible.
Looking at how the splice was done in the engine compartment might give an idea of the quality of the work that's under the dash.

When Chrysler bypassed the multiconnector, usually the fusible link was moved to the starter relay. Sometimes a second link was added depending on how the size of the wires and whether the ammeter was also used as a distribution point. Unfortunately maybe the person who did the modification did not consider the link important.
Thanks. I am thinking I will do just that (put a link on the starter relay end). Any thoughts on a replaceable fuse rather than a link? I'll also try to get underneath and look at the ammeter connections if I can get to them. It's tight under there and I am not small or flexible, lol.
 
Disconnect the battery. I melted a watchband off my arm reaching under the dash and touching the ammeter pegs.
 
Thanks. Based on all of the above, it would appear the fusible link was cut out and replaced with a soldered wire that runs through the port (not pins) of the bulkhead connector to the ammeter. The first pic is as found, the second pic after I removed the tape.
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Thanks. I agree.

Thanks. I am thinking I will do just that (put a link on the starter relay end). Any thoughts on a replaceable fuse rather than a link? I'll also try to get underneath and look at the ammeter connections if I can get to them. It's tight under there and I am not small or flexible, lol.
Hopefully they left the original wire and made a good splice to it.

I can't recall whether I could ever see the back of the ammeter from underneath - even with a mirror. Since everthing is on the workbench right now I'm not going to be any help there. I *think* the only way to really see the ammeter posts clearly is to remove the dash panel. I'm pretty sure that's what I did when removing the panel. Lemme check my notes but I'm pretty sure I removed many of the connectors from underneath, but the ammeter once the panel was partially out.


Maxi fuse vs fusible link - next post
 
I think its easy to install a fusible link. LOL. There are some people who have used maxifuses. The mini-mopar (front wheel drive) website has a page where they compared the fusible links used to the maxifuses used on the same car in later years.

For a fusible link, its two wire sizes smaller than the smallest wire being protected.
So the normal fusible link is 16 ga for us. I found a 16ga link with a ring terminal sold for Ford applications. I'll get the details and photo later todaywhen Im at the garage. I also bought a nice repop link from Bill Evans. You could use that by splicing.

The main job of the fusible link is to burn up when the battery is accidentally grounded on an unfused circuit. For example when your wristwatch contacts a hot post and ground and you can't pull away fast enough!
 
here's the Mini-mopar page with the link and fuse info
http://www.minimopar.net/electrical-links.html

This diagram based on the '73 B-body 60-amp wiring shows one way the factory wired to reduce the load on the mulitconnector.
It is very similar to what the factory planned for 67-9 a-bodies - although I'm not aware of any evidence that any 67-9 a-bodies were actually wired this way.

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In this arrangement, the stream of current for recharging the battery is split off at the terminal block.
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It would also work just as well if the original R6A was left in place.
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In fact on some '73 up A-bodies with rear window defroster grids, the ammeter post had multiple ring terminals on it.
 
Thanks. I agree.


Hopefully they left the original wire and made a good splice to it.

I can't recall whether I could ever see the back of the ammeter from underneath - even with a mirror. Since everything is on the workbench right now I'm not going to be any help there. I *think* the only way to really see the ammeter posts clearly is to remove the dash panel. I'm pretty sure that's what I did when removing the panel. Lemme check my notes but I'm pretty sure I removed many of the connectors from underneath, but the ammeter once the panel was partially out.


Maxi fuse vs fusible link - next post
I was able to get a good look at all the ammeter wiring from under the dash. The splice looks good...
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...and the connectors on the back look original and clean. Could not verify tightness because I could not reach them (only see them), but no reason to suspect they are loose.
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Back to the ignition switch wiring, I found a not-so-great splice into it for the aftermarket tach, and a bunch of loose electrical tape instead of shrink tube and cable ties, so I tidied all of that up.
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Still plan to swap out the switch. I'll do some searching for a suitable fusible link to install at the starter relay. Looking forward to the info on the one you used. Thanks for all your time, suggestions and advice. It is much appreciated!
 
Your key probably looks different. The ignition key (maybe switch too) was changed many years before I bought it.
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To seperate the lock cylinder from the switch, turn the key to run (or any position other than off) and deperess the brass pin.

I bought a Standard US50 switch (left). Quality seems OK and the positions are correct for '67.
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Thanks for the info. I have a replacement switch and got the old one out of the dash easily enough, BUT... I wasn't ready for the tiny brass tumbler springs to be all loose when I separated the cylinder. I would swear one of them launched when the cylinder came out, and I'm not optimistic about being able to find it. It looks like the last spring is missing (if there is one)...
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That tumbler doesn't seem to move much when I turn the key. I am hesitant to put this back together if it is missing a spring. Afraid I won't get it back apart again if there is an issue. Any thoughts? Am I calling a locksmith?
 
You can leave a pin and spring out and it will work. The pins you use do need to match the cuts in the key though.
 
I was able to get a good look at all the ammeter wiring from under the dash. The splice looks good...
View attachment 1715554449
...and the connectors on the back look original and clean. Could not verify tightness because I could not reach them (only see them), but no reason to suspect they are loose.
View attachment 1715554447
Back to the ignition switch wiring, I found a not-so-great splice into it for the aftermarket tach, and a bunch of loose electrical tape instead of shrink tube and cable ties, so I tidied all of that up.
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Still plan to swap out the switch. I'll do some searching for a suitable fusible link to install at the starter relay. Looking forward to the info on the one you used. Thanks for all your time, suggestions and advice. It is much appreciated!
That's funny you mention aftermarket tach. One of the things I'm doing is rewiring my aftermarket gages and tach to get power from the fusebox.
If the car was optioned with the tachometer in dash, then there was a fuse for it. So I basically copied the factory.

Fusible links.
I bought these 'just in case' needed as replacements or to rework the battery feed.

Top two are from Bill Evans, Evans Wiring.
Blue flag with ring terminal is for a B-body application.
Yellow flag with Packard 56/58 terminal in a connector housing is for A-bodies.
Bottom one speaks for itself.
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Personally I'd be inclined to leave teh starter relay and place the fuse where the splice is. That's just me and mostly because the ring terminals on the starter relay looked OK, so I'd leave them alone. But either way will work fine.

To splice in the A-body one, I'd first try asking Bob if he would sell an male extra connector housing and 2 mating housing for the female terminals.
Then buy the appropriate size Chrysler/Packard 58 style female terminals. For the original wire - that's either 10 or 12 ga.
By 1973 or 74 Chrysler switched to using bullet style connector. Those seem to have more contact surface area. Just mentioning it if your open to not so original looking options.
 
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One of the causes for failures of these terminals in the multi-connector is long periods of high current charging.
Since the alternator output feed through the multiconnector in the bulkhead carries the charging current and the current for powering the ignition, and everything else, at some point its probably worth checking its condition as well.

Here's the bulkhead terminal from the alternator output wire (R6) when I removed it. This a reproduction harness. I'm pretty sure the insulation melted when I had to the recharge a low battery while driving. It was very difficult for me to keep the charging rate below 20 amps, never mind 5 or 10 amps, for the whole trip back to our base camp - roughly 20 minutes.
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From the outside of the connector it looked ok. Only when I removed the terminal could I see the heat damage.
I mention this only because we don't know why the previous owner made the through wire splice.
 
Since you obviously will be driving in the dark with this car, let me bring this up now. Our cars came with 6012 headlight bulbs. Many replacement headlights since the mid-70s use more power than the 6012s did. The headlight wiring circuit is long and has many connections, and the wiring is only 16 and 18 ga in our A-bodies. So for your use it would be worth considering a headlight relay circuit. You can make your own, buy a kit from Daniel Stern, or buy a premade, almost plug and play from Rob Yule (screen name crackedback). Power it off the alternator and that will also take about 9 amps of current off of the bulkhead connectors.
 
Thanks for the info. I have a replacement switch and got the old one out of the dash easily enough, BUT... I wasn't ready for the tiny brass tumbler springs to be all loose when I separated the cylinder. I would swear one of them launched when the cylinder came out, and I'm not optimistic about being able to find it. It looks like the last spring is missing (if there is one)...
View attachment 1715554580
That tumbler doesn't seem to move much when I turn the key. I am hesitant to put this back together if it is missing a spring. Afraid I won't get it back apart again if there is an issue. Any thoughts? Am I calling a locksmith?
Glad you found the spring!
I'm surprised the cover came off.
Maybe someone will have a suggestion about resecuring it.
 
Glad you found the spring!
I'm surprised the cover came off.
Maybe someone will have a suggestion about resecuring it.
Not sure what you mean about the cover. The springs are contacting a 'floating' piece of metal that was no longer restrained when I pulled the cylinder out of the switch body. I'm surprised only one of the springs launched. Is there supposed to be a cover that holds it all together? That would make sense. The key action is a little sloppy, so maybe its time to re-key?
 
Not sure what you mean about the cover. The springs are contacting a 'floating' piece of metal that was no longer restrained when I pulled the cylinder out of the switch body. I'm surprised only one of the springs launched. Is there supposed to be a cover that holds it all together? That would make sense. The key action is a little sloppy, so maybe its time to re-key?

I can take another picture of cylinder I removed from my '67 in the next day or two. That sheet metal was crimped into the casting so I didn't touch it. I don't know if its original to the car as the door keys didn't match. With mismatched keys to begin with, I thought it made sense for me to buy new keys and cylinder.
The repo has some slop in it too and I'd have the keys fitted a little better if there was a local locksmith I trusted. I also bought new door locks but not sure I'm going to use them.
Maybe start a thread about ignition cylinder and one of the guys here who knows about such things can provide more guidance. Most people like to have the ignition cylinder and door locks using the same key. At this point I'm so use to using two keys it doesn't bother me...
 
How about a summary?

1..What does and does not work?
2..What have you gained on the problem if any?
3..What do you think it is and why?
4...What do you think it is NOT and why?
 
UPDATE: The problem hasn't resurfaced for a couple of weeks now. No way to know for sure exactly what fixed it (if it is in fact fixed), but my gut tells me it was a poor connection somewhere in the ammeter feed.
The things I've done so far are:
1. Verified that the bulkhead connector was not the problem.
2. Went through all accessible parts of the harness cleaning, tightening, and securing connections. Removed/replaced a lot of loose electrical tape. Used dielectric grease when appropriate.
3. Replaced ignition switch (the switch was sloppy and needed replacing anyway, but the switch alone doesn't fit the original symptom).
4. Replaced the ballast resistor.
5. Replaced the mechanical voltage regulator with a solid state replica.
6. Added a 16 gauge fusible link at the starter relay for safety's sake. The original had apparently been removed when they modified the ammeter feed to bypass the bulkhead connector.
 
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I had a very similar situation. 70 mph 4 lane highway and lose power to everything. I still havent fixed mine. Frustrated. 2 years in storage now...
Electrical/wiring will lead you down a rabbit hole...get factory schematics.
Good luck

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