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Factory original Chrysler ammeter-based Charging System and additional loading. Load placement matters!

Scatransit said:
If one wanted to replace a deteriorated amp gauge insulator, what type of material would you recommend and where would you purchase? I've found some glass-mat pcb material on ebay as well as thermal fiberboard, either can be cut to size. Your thoughts appreciated.
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If fabricating replacements, any good quality insulting material should work as long as it can tolerate some heat. Just remember to account for the locating tabs/notches in the insulator that centers the ammeter stud pass-through in the cluster frame.

Haven’t seen these reproductions myself, but someone is making these based on the original design.
 
72RoadrunnerGTX said:
If fabricating replacements, any good quality insulting material should work as long as it can tolerate some heat. Just remember to account for the locating tabs/notches in the insulator that centers the ammeter stud pass-through in the cluster frame.

Haven’t seen these reproductions myself, but someone is making these based on the original design.
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I have purchased the insulators shown in the link, they are quality and seem to be the same as original.
 
Scatransit said:
If one wanted to replace a deteriorated amp gauge insulator, what type of material would you recommend and where would you purchase? I've found some glass-mat pcb material on ebay as well as thermal fiberboard, either can be cut to size. Your thoughts appreciated.
Click to expand...
Yes, find some thick standard pcb from some old electrical thingy you have laying around, grind off the metal tracks, drill holes for the gauge and you are set with something way stronger than original.

Did this on my car, should be a pic in this thread somewhere.
 
Thank you OP for this video, it was very helpful in understanding how the system works any why the shunt wire "fix" does little to address the problem. My vehicle was a former parts car which exchanged its good factory under dash harness for a very damaged one. Back in the late 90s I added a shunt wire that I thought at the time was helping deal with my dimming headlights. I also upgraded to a 90a alternator which I realize now just increased the charging systems ability to stress the bad connections even more.

After storing the car for 23 years I have it back on the road and working through the issues. I have added some aftermarket items and I want to rework how they are fed. I found a small fuse/relay block that I planned to use to feed three items: 1) HEI Ignition Module, 2) EFI Fuel Pump, 3) Fietch EFI Dual Quad setup.

If I feed these items from the fuse/relay block and tie that into the charging post of the alternator, Am I correct in my understanding that would isolate those loads outside the factory bulkhead terminals? Is there anything else to consider here? I was also thinking of moving the headlight load to a relay in this same distribution block, Can you offer any advice on this approach?
 
zombezoo said:
Thank you OP for this video, it was very helpful in understanding how the system works any why the shunt wire "fix" does little to address the problem. My vehicle was a former parts car which exchanged its good factory under dash harness for a very damaged one. Back in the late 90s I added a shunt wire that I thought at the time was helping deal with my dimming headlights. I also upgraded to a 90a alternator which I realize now just increased the charging systems ability to stress the bad connections even more.

After storing the car for 23 years I have it back on the road and working through the issues. I have added some aftermarket items and I want to rework how they are fed. I found a small fuse/relay block that I planned to use to feed three items: 1) HEI Ignition Module, 2) EFI Fuel Pump, 3) Fietch EFI Dual Quad setup.

If I feed these items from the fuse/relay block and tie that into the charging post of the alternator, Am I correct in my understanding that would isolate those loads outside the factory bulkhead terminals? Is there anything else to consider here? I was also thinking of moving the headlight load to a relay in this same distribution block, Can you offer any advice on this approach?
Click to expand...
I would still by-pass both Packard terminals in the charge path at the bulkhead connector at a minimum. But yes, connecting your add-on loads at the alternator, not the battery, will remove those loads from the stock charge path while the charging system is in operation. Be sure to have a look at the “Not-so-stock” loading video.
 
72RoadrunnerGTX said:
I would still by-pass both Packard terminals in the charge path at the bulkhead connector at a minimum. But yes, connecting your add-on loads at the alternator, not the battery, will remove those loads from the stock charge path while the charging system is in operation. Be sure to have a look at the “Not-so-stock” loading video.
Click to expand...

What do you think of Anderson Powerpole/PowerWerx connectors? I could unpin the two factory packard terminals, remove them from both factory side harnesses and add a Powerpole connection with a short bit of wire through the connector? Would allow me to retain the ability to disconnect the sides of the connector. I might even try it on my trashed harness first to see if it improves the system before I commit to completely replacing both harnesses.
 
zombezoo said:
What do you think of Anderson Powerpole/PowerWerx connectors? I could unpin the two factory packard terminals, remove them from both factory side harnesses and add a Powerpole connection with a short bit of wire through the connector? Would allow me to retain the ability to disconnect the sides of the connector. I might even try it on my trashed harness first to see if it improves the system before I commit to completely replacing both harnesses.
Click to expand...
Use them all the time, you would want to use the PP120s for the charge path. Really no electrical need for a disconnect in those wires, run the charge path wiring straight through a rubber grommet to the ammeter. Pretty easy to pull back out if you need to service anything. Upsize the wires a bit if you are running a 95 amp alt.
 
72RoadrunnerGTX said:
Use them all the time, you would want to use the PP120s for the charge path. Really no electrical need for a disconnect in those wires, run the charge path wiring straight through a rubber grommet to the ammeter. Pretty easy to pull back out if you need to service anything. Upsize the wires a bit if you are running a 95 amp alt.
Click to expand...
what about wire? i see a lot of CCA (copper clad aluminum) wire, do you have an automotive wire mfg you prefer?
 
72RoadrunnerGTX said:
Use them all the time, you would want to use the PP120s for the charge path. Really no electrical need for a disconnect in those wires, run the charge path wiring straight through a rubber grommet to the ammeter. Pretty easy to pull back out if you need to service anything. Upsize the wires a bit if you are running a 95 amp alt.
Click to expand...
Agreed that there isn't a need for a quick disconnect on the 8ga charge wire from the alternator to the battery. I will just route through a grommet and connect between ammeter and battery and ammeter and the alternator distribution lug and lug to alternator in the engine bay as shown in your diagram with fusible links.

For connections, I'm assuming you solder and heat shrink the fusible link connections. What about the ring terminals at the ends? Do you have a preference for a particular brand of terminal? Crimps with integrated heat shrink ok?

I'm planning to do a slightly modified approach on the alternator side of the ammeter: 8ga wire from ammeter to distribution lug, extend original factory ammeter connection with 10ga to lug through grommet and add fusible link as shown. Add my aftermarket relay/fuse box using the lug and run my aftermarket loads through there. I planned to use this Fuse/Relay Block and 12ga for: Headlights/Brights, Fuel Injection System with integrated fuel pump, HEI Ignition Module/Coil

Additional question: when rewiring the headlights, how did you go about rewiring? Reuse the stock plugs? What kind of terminals did you use?
 
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Thanks again to 72RoadrunnerGTX.
For the first time in 25 years, my ammeter works like it's supposed to. I removed the shunt wire I had installed, and I now have upgraded wiring that actually supports both the factory loads and my aftermarket ones.
All loads now on the alternator side of the ammeter, only battery on the other side.

Gauge draw during fuel pump prime before start.
Heavy charging falls off shortly after engine starts.
I now have 14.3v at the coil + (previously like 12.7v)

Run.jpg


Start.jpg


Draw.jpg
 
72RoadrunnerGTX said:
Missed this one, you can get ceramic replacement headlight bulb connectors. High wattage halogens will generate some heat.
Click to expand...
Another question, found this post, what are your thoughts on this modification? Not necessary if the firewall connectors are bypassed per your upgraded charging system video?

I still get some discharge at idle with the lights on, I have stripped out bolt holes at the voltage regulator that I plan to fix this weekend. I did add a ground wire that runs from the alternator to a couple points including the voltage regulator but its not as tight as I would like it to be yet. A bit more idle speed might be enough as it jumps back to charging as soon as I give it a little throttle.
I'm running a new Tough Stuff 130A unit.

"Improving the power side involves putting the alternator field circuit on a relay. Chrysler called this a "Field Loads Relay" and installed it in heavy-duty charging systems. You'll need another SPST relay just like the one that powers the HEI module. Find the wire that feeds line voltage to the voltage regulator when you turn on the ignition. Cut it. If you're running a '70-up system (two field terminals on the alternator, flat regulator with triangular 2-prong plug), cut the wire upstream of the splice that also sends line voltage directly to one of the alternator's field terminals. The ignition switch end of this wire goes to terminal 86 of the relay. The regulator/field end of the wire goes to terminal 87 of the relay. The 85 terminal of the relay gets grounded. The relay's 30 terminal goes to battery + (via an appropriate fuse of about 5A to 10A, depending on alternator spec). This way, turning on the ignition shows the regulator the actual battery voltage, not line voltage after dropping through firewall connectors, wiring harness "master welds", and ignition switch."

 
zombezoo said:
Another question, found this post, what are your thoughts on this modification? Not necessary if the firewall connectors are bypassed per your upgraded charging system video?

I still get some discharge at idle with the lights on, I have stripped out bolt holes at the voltage regulator that I plan to fix this weekend. I did add a ground wire that runs from the alternator to a couple points including the voltage regulator but its not as tight as I would like it to be yet. A bit more idle speed might be enough as it jumps back to charging as soon as I give it a little throttle.
I'm running a new Tough Stuff 130A unit.

"Improving the power side involves putting the alternator field circuit on a relay. Chrysler called this a "Field Loads Relay" and installed it in heavy-duty charging systems. You'll need another SPST relay just like the one that powers the HEI module. Find the wire that feeds line voltage to the voltage regulator when you turn on the ignition. Cut it. If you're running a '70-up system (two field terminals on the alternator, flat regulator with triangular 2-prong plug), cut the wire upstream of the splice that also sends line voltage directly to one of the alternator's field terminals. The ignition switch end of this wire goes to terminal 86 of the relay. The regulator/field end of the wire goes to terminal 87 of the relay. The 85 terminal of the relay gets grounded. The relay's 30 terminal goes to battery + (via an appropriate fuse of about 5A to 10A, depending on alternator spec). This way, turning on the ignition shows the regulator the actual battery voltage, not line voltage after dropping through firewall connectors, wiring harness "master welds", and ignition switch."

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Click to expand...
The later field relay had nothing to do with alternator output, was to address the factory higher output alternator’s higher field current draw. Can be used to address battery/regulator reference voltage drop issues but won’t make the alternator output any more current vs rpm. What idle speed? I run the Tuff Stuff 130 amp, can’t turn on enough loads to bring it to a discharge running an idle speed of around 850-900 rpm. What lights are you running?

I do talk about the field relay towards the end of this video on charging over-voltage related voltage drop.
 
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72RoadrunnerGTX said:
Prefer marine grade tinned copper wire for this application.
Click to expand...
Link not working for me, but marine grade tinned wire is good. The Tin helps prevent corrosion of the wire, and marine grade insulation I believe is low flammability? There are different insulation materials for marine wire that have different properties. I think the XLPE insulation would be good for under hood use (Temperature rating and resistance to oils and fuels).
My marine wire knowledge is not that good. I usually just stick with the lower cost automotive SXL/GXL/TXL insulated wires for my cars.
 
451Mopar said:
Link not working for me, but marine grade tinned wire is good. The Tin helps prevent corrosion of the wire, and marine grade insulation I believe is low flammability? There are different insulation materials for marine wire that have different properties. I think the XLPE insulation would be good for under hood use (Temperature rating and resistance to oils and fuels).
My marine wire knowledge is not that good. I usually just stick with the lower cost automotive SXL/GXL/TXL insulated wires for my cars.
Click to expand...
Amazon link, still works from here. Just an example.

Ancor 111002 Tinned Copper Wire, 8 AWG (8mm2), Black - 25ft​

 
72RoadrunnerGTX said:
The later field relay had nothing to do with alternator output, was to address the factory higher output alternator’s higher field current draw. Can be used to address battery/regulator reference voltage drop issues but won’t make the alternator output any more current vs rpm. What idle speed? I run the Tuff Stuff 130 amp, can’t turn on enough loads to bring it to a discharge running an idle speed of around 850-900 rpm. What lights are you running?

I do talk about the field relay towards the end of this video on charging over-voltage related voltage drop.
Click to expand...

850 rpm.

If weather cooperates this weekend, I will fix the mounting bolt situation on the voltage regulator and see if that fixes the issue.

Thanks for the reply.
 
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