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Overcharged?

THIS is gold.
Wow, all this time and worry and it's that easy...
That's what I'll do.
I really can't thank you enough.

And that's 12 ga?

Man Thank You ALL again!

That's what I have ilustrated on my diagrams at the dc.com link... just that I made some mods along the time thinking on better ideas while I was learning.

stock are 12. Bypassing the bulkhead paths 10 gauge is pretty much enough but I think he used 8. As I ilustrated on later diagrams at my dc.com threads, I'll be keeping the bulkhead alt path still in use when reassembling my Charger so will keep 10 working with the existant 12. With a better output capacity alt, the batt side barelly will get loads. Sure will be energized and some load will be running throught, but the main will be running on alt side.

Is just like using dual pipes to feed water to the source. You can use two 1/2" pipes, or just one 1" pipes to provide about same ammount of water. Sure some resistance it comes on every connection, and here is where the load will run primary by the easier path, but just like water and pipes, when having conections there is not a total restriction to the water. Here is where the ohms law also plays.
 
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Does this cause Ammeter to NOT function afterward? Probably a dumb question at this point.
I can cancel my order from Classic! Save nearly $800!

Thank You!!

No, the only way to "bypass" the ammeter is linking together the alt and batt wires at any point... straight to batt, starter relay stud... starter motor stud.

At the end making this, you are sill feeding the car load request through the bulkhead but saving the batt recharge load out of this path, running straight to the batt by the jumper wire. Hence why the charge load is being saved and bulkhead is not getting it, which is the big problem. BUT it won't get load enough going throught the amm to get a real reading

The load variation causing melting at the bulkhead point it comes mainly from the batt request when is discharged and you rev up the engine with stock alts, and this load varies continuously depending on batt charge status, without your control. But the car load request uses to be more less constant and easy to control just knowing how much accesories are being turned on. You can't controll the batt load request when is requesting charge, but you can control the accesories load request turning on or off those.

this charge load is added to the car load at the bulkhead connection on black wire, but on red wire the only load is the bat charge ( on Charge status ). Hence why the red wire survives better than the black wire
 
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Does this cause Ammeter to NOT function afterward? Probably a dumb question at this point.
I can cancel my order from Classic! Save nearly $800!

Thank You!!

Adding a bit more to my previous reply

The batt and alt jumping wire which is the most tipical mod ever made after this Mopar bulkhead failure makes exactly this, the ammeter "restriction" makes all the loads running through the easier path once the jumper wire is added. So you don't get discharge reading on ammeter because with engine off, just like when reving up the engine and charging the batt won't get you a charge reading. The load coming from batt to feed the main splice into the cab also will run through the jumper wire through the alt wire too, just like the extra load requested by a discharged batt on charge status. On both stages, the ammeter is being "bypassed" by its own nature about the small restriction it gets to the load by its own presence as a default.

Just like water, with a path without any kind of restriction, most of its flow will run throught that path, but adding some restriction, all paths will begin to "equalize" its flow capacity. Hence why I'm in peace using the quick disconect link wire on 10 gauge along with the stock wiring ( bulkhead and 12 gauge). Loads will be shared by both conections in a more less shared restriction capacity, but I will make this just because I want to keep the disconect hability just like stock wiring on all the wiring. Is just about personal preference.

Sure a path without restrictions (conections) is "better", but also there are dozens of ways to cook a pork for while you know what are you doing.

AS I QUITE OFTEN SAY... Sure there are precission maths, and more technical info involved, but the final GOOD result is PROOVED to work making this and I just post the info on the easier way to understand, being just BASIC.

This extra, or bigger charging path is NOT my invention, but also something MaMopar made, ilustrated on their own diagrams and I just refreshed and explained graphically (I think even getting them made a bit better). It was made on several ways along the years. I have found 2 or 3 diff ways it was made on the 71/74 period at least, which is the period I of course know better, being my car a 74 and working based on 71/74 diagrams.

This extra/bigger paths have being supported and experienced by several other members of several other Mopar boards along the years which are also electrically inclined. So I'm not crazy or mad when I'm talking about this, as some guys pretend to stablish thread after thread.

And the way to understand how the system work is also shared by these same kind of guys...
i.e.:
http://www.heritech.org/cuda/Charge.html

Made by a guy known as Mattax at several other boards ( FABO, Moparts )
 
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Understood!

So looks to be easily done.
Now, when I go to make the RED wire from Fusible Link, should I leave blue LINK wire as is from starter switch? Or connect Fusible wire as PART of One wire to NEG side of Ammeter? I see that really they are as ONE between both + and = posts of Ammeter..

This makes much more sense than that high resistance Packard thing! Red wire here, does attatch In PARALLEL or connect to Fusible Link?
Screenshot_20220327-114711_Chrome.jpg
 
First, careful referring to ammeter connections as + an -, both connections are positive. Battery side (red) and alternator/load side (black). The original fusible link needs to be there.

For that ’69 car, stock loads, I’d remove the factory fusible link Packard terminal from the engine compartment side of the bulkhead. Cut off the terminal and butt splice (quality crimped butt splice, soldered, heat shrink tubing) to a 10ga red wire, route it through a good firewall grommet to the ammeter. Try to keep as much length as possible on the fusible link.

You can leave the 12ga factory red wire in place on the inside of the bulkhead connector. No need to leave it connected to the ammeter. Tape off any unused exposed connectors.

For the alternator feed (black wire), again, stock loads, I’d run a new 10 ga from the alternator to the ammeter directly through the firewall grommet, no disconnects at all. You can leave the existing 12ga factory black wire in place, I prefer to open up/rebuild the engine harness, remove and replace/upsize the original 12ga run, wrap back up for a factory appearance, not a fan of unnecessary parallel circuits.
 
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First, careful referring to ammeter connections as + an -, both connections are positive. Battery side (red) and alternator side (black). The original fusible link needs to be there.

For that ’69 car, stock loads, I’d remove the factory fusible link Packard terminal from the engine compartment side of the bulkhead. Cut off the terminal and butt splice (quality crimped butt splice, soldered, heat shrink tubing) to a 10ga red wire, route it through a good firewall grommet to the ammeter. Try to keep as much length as possible on the fusible link.

You can leave the 12ga factory red wire in place on the inside of the bulkhead connector. No need to leave it connected to the ammeter. Tape off any unused exposed connectors.

For the alternator feed (black wire), again, stock loads, I’d run a new 10 ga from the alternator to the ammeter directly through the firewall grommet, no disconnects at all. You can leave the existing 12ga factory black wire in place, I prefer to open up/rebuild the engine harness, remove and replace/upsize the original 12ga run, wrap back up for a factory appearance, not a fan of unnecessary parallel circuits.
Sounds like a plan!
Maybe I'll get my Tach & fuel guage back with this repair too... (Fingers crossed!)

That helps a lot!
Thanks!!!

I'd replace the 16 gauge fuse link for a 14 gauge one on this job, specially if upgrading the alt (which as I mentioned on several threads is actually the FIRST STEP should be made even before the wiring upgrade but also before the bulkhead meltdown, since even with a more powerful alt, the stock wiring will survive better) to correctly match the size of the wire gauge being used. Tipically the fuse link to be used is 2 sizes smaller ( 4 numbers ) than the wire where is attached. So if using 10 gauge wire, 14 gauge fuse link is the one to be used. So you won't need to modify the existant 16 gauge fuse link terminal but use a new one to the new wire. On this way, nor the stock red amm wire or the existant 16 gauge fuse link will be used but the new wire added out of the bulkhead with a new fuse link, both thicker. You can remove those in fact just for cleaning wiring job. Just that the red wire is taped to the dash harness so is a bit harder. But existant fuse link is easy to remove from engine bay side.

Using the thicker fuse link along with a better alt will guarantee that in case of a heavy batt discharge status, the extra power provided by the bettter alt to recharge the batt will go throught the thicker fuse link with more headroom to hold the load without heating it up able to melt down the fuse link cover or even blowing it up, althought this last is not easy to happen when batt is being recharged, however depending on charge level and how long it gets a high load charge level it can get hot enough to melt a bit the stock 16 ga fuse link cover.

Fuse links are available on parts dealers shops on help section blisters. Some of them it get even the flag label saying FUSE LINK, just like the stock one.

Another option is to replace the fuse link with maxifuse. That is being a favorite proceeding latelly since is an easier to service part in case of failure, but I'm quite in peace with fuse links, specially if keeping somehow the stock look as part of the job by owners preference.
 
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In fact, on Mopar diagrams where the charging wiring is reinforced for fleet cars or trailer tow equipped cars with +60 amps alts is being used a 14 gauge fuse link is shown on them.
 
In fact, on Mopar diagrams where the charging wiring is reinforced for fleet cars or trailer tow equipped cars with +60 amps alts is being used a 14 gauge fuse link is shown on them.

Thanks! I was about to ask that! Looking at the car, Im trying to decide how or where to GO INTO the dash with the 10 Ga black wire? A few cars Ive had I now remember theyve had that wire made and just ran through where "J" or the originl Black feed melted. Looks like they just removed the INSIDE Female Packard connector and wires that go to the SPLICE as well... R6-12BK splices off to R6A-12BK to ammeter-
Thanks!!
20220328_174329.jpg
 
just go straight to the ammeter stud with a hole throught the firewall and a grommet. The splice will be feeded through the existant amm black wire up to the splice. The extra thickness for the new wire is to feed the extra load required by a discharged batt throught the amm if the moment floats on.

If your car is auto, you could use the Reverse light dimple on firewall and drill it out just right there. On my car I didn't want to drill an extra hole ( althought factory did ) but used an existant grommet used on 74 for the A/C harness. I just enlarged the existant grommet and decided to run the two new wires along with the A/C wires.

But once again, the best result of this upgrade is run a better alt, able to feed AT LEAST anything between 45-55 amps at iddle, depending on car equipment. Althought I'm pointing out for something closer to 65. IT IS NOTICEABLE this extra power when you are driving down a tropical heavy rain and turning on max speed wipers, A/C and headlights. TRUST ME. My existant alt ( stock 80s replacement alt ) able to feed 45-48 amps at iddle is still short of power under this driving condition and city traffic. BTDT. Even the ignition system is affected.

I'm also running relays for each one of the A/C Speeds and headlights. 6 in total, everyone down the dash. No visible relays on engine bay, everyone hidden down the dash or kick panel. And I'm taking the power for the relay network from the amm stud. This is not posible with just the bulkhead conection. This relay setup keeps also free of loads the stock existant main splice network between amm and bulkhead
 
Curious, anyone ever by accident leave a "Trickle Charger" connected for say 2 days? With the BATTERY CABLES Connected too?
(Oooopsie)
I can tell ya why NOT to-

Thanks in advance!
A trickle charger shouldn't hurt anything, as it only maintains the voltage at what a fully charged battery would have (13 - 14 volts). Just make sure the charger is designed to reduce the charge when the battery is at the correct voltage.
If something else on the car went up in smoke, it would either have to be because of a dead short, a failing switch or something was drawing current when it shouldn't have been.
 
2 amp trickle over long term will dry out the battery and render it useless...been there done that one ....couple of days here and there is fine


Yeah may have done just that. Doesnt wanna hold 12.6 V I'll probably replace it.
 
So, me being a "Purist", what can be done to eliminate this from the future? I also wondered "Surely an UNDERPOWERED alternator could have also caused more draw upon say, a 60 amp alternator if conditions were right just once"? Maybe a 70/100 amp I need? I dont have anything on this car that wasnt factory.

Thanks!!!

Bypass the Ammeter inside the car (which is a fire waiting to happen).

This link will provide all the information you need;
http://www.madelectrical.com/electricaltech/amp-gauges.shtml

If you have a weak or dead battery, just recharge it completely (with a physical battery charger) rather than relying on the alternator to renew it. In some cases, that's not possible, but the risk of electrical fires or meltdowns with 50-year old wiring is far less with that method. I trust NOCO chargers, they are some of the best on the market IMHO.
 
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Reading through this thread I believe most of the info has nothing to do with the original issue. IMO, originally the question asked had to do with whether a trickle charger could have caused the overheating of the bulkhead connector which was answered. The real reason for the overheated connector really didn't get dealt with. The bulkhead connector that failed is the main source of power feed for most everything. It sources all the lights, Ignition switch, heater blower motor, Wiper motor, Radio.....Pretty much everything. More than likely, what happened was driving at night with the headlights and heater and everything on for long periods, overtaxed that connector with all the current flow needed to power everything is what caused that failure. Those two components alone can use enough current to overload those bulkhead connectors. Those Packard connectors are not rated for all the current flow that gets sent through them especially when the get a little dirty or loose. For my dollar, just by adding relays for the headlights goes a long way to eliminate current flow through the firewall by eliminating those amps. Another big amperage user is the blower motor. They can draw around 25 amps on high and when they get dirty and dried out they can draw an extra 5 or 10 amps pretty easily. A lot of people want to by-pass or eliminate the amp meter and eliminate the firewall connectors which is an ok idea but I believe it to be way more important to cut down on the current flow that burns up the wiring and connectors.
 
Exactly.. Loose connection or Air gap is all it takes with that much Amperge pull.. I saw that "Ditch the Ammeter comment" AGAIN and about puked.. LoL


10-4!

You know, that's the first thing I look for when I talk to the 70-year old owners of these cars, 'you didn't bypass the factory ammeter did you!?' :eek:

Exactly as posted above, it's a host of conditions that will create the environment where the amp draw causes these to melt or (worst case scenario) electrical fires. As noted above in the thread, near dead starting battery, proceeding to then drive at night with the headlights, heater, and radio on is a likely scenario to cause this.

Even the 44,000 (original) mile 77' Dodge M880 we picked up, had the notorious ammeter melted with a replacement Stewart Warner up under the dash. Who knows when that was put in.

Simple things like a headlight harness using relays, that pull power directly from the battery, rather than through the bulkhead is a great upgrade, again, not sure if the purists would approve!

Mopar problems. Got to love them! Looking at my car may put some of these types in the ER.

Not that any of this will matter to the next generation, who will end up scrapping these dinosaurs for Teslas lol.
 
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Reading through this thread I believe most of the info has nothing to do with the original issue. IMO, originally the question asked had to do with whether a trickle charger could have caused the overheating of the bulkhead connector which was answered. The real reason for the overheated connector really didn't get dealt with. The bulkhead connector that failed is the main source of power feed for most everything. It sources all the lights, Ignition switch, heater blower motor, Wiper motor, Radio.....Pretty much everything. More than likely, what happened was driving at night with the headlights and heater and everything on for long periods, overtaxed that connector with all the current flow needed to power everything is what caused that failure. Those two components alone can use enough current to overload those bulkhead connectors. Those Packard connectors are not rated for all the current flow that gets sent through them especially when the get a little dirty or loose. For my dollar, just by adding relays for the headlights goes a long way to eliminate current flow through the firewall by eliminating those amps. Another big amperage user is the blower motor. They can draw around 25 amps on high and when they get dirty and dried out they can draw an extra 5 or 10 amps pretty easily. A lot of people want to by-pass or eliminate the amp meter and eliminate the firewall connectors which is an ok idea but I believe it to be way more important to cut down on the current flow that burns up the wiring and connectors.

Yep 100%. Even replacing an Ammeter won't eliminate the problem. Ive seen 3 e bodies 2 B bodies with VOLTMETERS and NEW, MELTED bulkhead PACKARD connections.. Just me found it easier to unplug the harness, push the R6-12BK wire thru the "Firewall" and solder them together under the dash. One could use an inline 90Amp fuse I guess? Few ways to "Attack" this thing.
1. Eliminate that LOOSE conection,
2. Close up the failure associated with wiring's "4 biggest enemies"..
M.A.L.T.
Material/Area/Length/Temperature
Never forget the Dialectric Grease! ;-)
 
You know, that's the first thing I look for when I talk to the 70-year old owners of these cars, 'you didn't bypass the factory ammeter did you!?' :eek:

Exactly as posted above, it's a host of conditions that will create the environment where the amp draw causes these to melt or (worst case scenario) electrical fires. As noted above in the thread, near dead starting battery, proceeding to then drive at night with the headlights, heater, and radio on is a likely scenario to cause this.

Even the 44,000 (original) mile 77' Dodge M880 we picked up, had the notorious ammeter melted with a replacement Stewart Warner up under the dash. Who knows when that was put in.

Simple things like a headlight harness using relays, that pull power directly from the battery, rather than through the bulkhead is a great upgrade, again, not sure if the purists would approve!

Mopar problems. Got to love them! Looking at my car may put some of these types in the ER.

Not that any of this will matter to the next generation, who will end up scrapping these dinosaurs for Teslas lol.

Yep- Luckily I wont be around to see that day. I'd rather be wadded up in mine & buried all as one with it. LoL
I'll take it with me then! ;-)
 
Even the 44,000 (original) mile 77' Dodge M880 we picked up, had the notorious ammeter melted with a replacement Stewart Warner up under the dash. Who knows when that was put in.

Again, the later plastic framed truck ammeter melt downs (as specifically addressed in the “MAD” article) cannot be conflated with the earlier passenger car ammeters in discussion here. The construction of these ammeters is completely different. The notion that the passenger car ammeter with well-maintained connections and insulators, running anything close to stock loads, is “a fire waiting to happen” has no basis in fact.
 
Again, the later plastic framed truck ammeter melt downs (as specifically addressed in the “MAD” article) cannot be conflated with the earlier passenger car ammeters in discussion here. The construction of these ammeters is completely different. The notion that the passenger car ammeter with well-maintained connections and insulators, running anything close to stock loads, is “a fire waiting to happen” has no basis in fact.

ABSOLUTELY AGREE..... The first instance has nothing to do with the second....in spite of what the "flaming ammeter" person proclaims or professes, without any facts, figures or calculations to substantiate the claim......
BOB RENTON
 
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