72 Swinger not charging battery

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Should I splice switched 12V from the relay I installed to the reg and alt blue so it's getting 12.3V?
Yes, 10v on a 12v cir is still a LOT of loss due to resistance. You NEED to track that down, cars have melted down on less. 0.2 to 0.5 (and 0.5 is pushing it) is the most drop you should expect to see on our cars if everything is working properly
green 399 mV
That says the VR is trying to provide a full ground to the alternator because it is only seeing 10V and wants to charge the battery etc
Maybe I will spring for one of those HUGE color laminated wiring diagrams.
best 25.00 you will spend I'm impressed you got as far as you did trying to follow the OEM diagram

When I just jumped battery + to the blue field wire bat voltage jumped to 13.7V
There you go.
Also something I forgot to mention is the ammeter in the dash indicates the battery is charging. I don't know how that could be because I tested the V out of the battery terminal on the alt and it shows the same as battery V. Doesn't the alt batt terminal go through the ammeter?
showing charge and 13.7V is pretty normal. The output of the ALT is essentially directly connected to the battery Plus (yes it goes through connectors and the Alt gauge) but if the output of the ALT is 13.7 the battery better show VERY close to 13.7 like 13.5 would be .2V drop through all of the connectors etc.
 
No. Load tested battery, it's pretty good. 12.6V fully charged.
What was the result of the load test?
12.8 v is what a new, good battery typically has at rest
The output of the ALT is essentially directly connected to the battery Plus (yes it goes through connectors and the Alt gauge) but if the output of the ALT is 13.7 the battery better show VERY close to 13.7 like 13.5 would be .2V drop through all of the connectors etc.
Yup. It's why an ammter is needed to show charging. A voltmeter only can show potential to charge. The problem here is there's a whole bunch of modifications and additions in this harness.
best 25.00 you will spend I'm impressed you got as far as you did trying to follow the OEM diagram
I don't know why you have so much trouble with the factory diagrams. No harder than following any other map. Take a colored pencil and trace the route. Then a draw schematic.

In any event with EFI and pumps and a relay added there is no way for us to know what the circuits look like. If you want to track battery charging with EFI, I've posted some ways this can be done with the factory ammeter. Or you can get a shunted ammeter. Good ones are available, just not cheap.
 
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With a factory '72 charging system, the setup could be like this.
1751666503661.png


With a relay
1751667895786.png
 
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Does anyone own a Snap On MT-952 amp meter or similar tester?
Would it be helpful in this particular situation?
Example from eBay:

 
Does anyone own a Snap On MT-952 amp meter or similar tester?
It's just a clamp on current tester

It's handy but I think I used it the most the day I got it and haven't used it since
 
Yes, 10v on a 12v cir is still a LOT of loss due to resistance. You NEED to track that down, cars have melted down on less. 0.2 to 0.5 (and 0.5 is pushing it) is the most drop you should expect to see on our cars if everything is working properly

That says the VR is trying to provide a full ground to the alternator because it is only seeing 10V and wants to charge the battery etc

best 25.00 you will spend I'm impressed you got as far as you did trying to follow the OEM diagram


There you go.

showing charge and 13.7V is pretty normal. The output of the ALT is essentially directly connected to the battery Plus (yes it goes through connectors and the Alt gauge) but if the output of the ALT is 13.7 the battery better show VERY close to 13.7 like 13.5 would be .2V drop through all of the connectors etc.

What was the result of the load test?
12.8 v is what a new, good battery typically has at rest

Yup. It's why an ammter is needed to show charging. A voltmeter only can show potential to charge. The problem here is there's a whole bunch of modifications and additions in this harness.

I don't know why you have so much trouble with the factory diagrams. No harder than following any other map. Take a colored pencil and trace the route. Then a draw schematic.

In any event with EFI and pumps and a relay added there is no way for us to know what the circuits look like. If you want to track battery charging with EFI, I've posted some ways this can be done with the factory ammeter. Or you can get a shunted ammeter. Good ones are available, just not cheap.
A single lead acid cell measures 3.1V fully charged. In my experience right after being taken off charge a 12V car battery may read 12.7 or 12.8 but 12.6V indicates a full charge. I use a Milton load tester (the kind with a big honking resistor) and the battery tests good. I drove it around today for a half hour with (total loss system with no charge from the alternator) and the battery was discharged down to 12.3V. The battery is fine.
 
It's just a clamp on current tester

It's handy but I think I used it the most the day I got it and haven't used it since
When I jump the blue alt/VR lead to batt + with the engine idling at 900 RPM, batt V jumps to 13.7. As for load from the EFI, fuel pump, and HEI, IGN 1 output was in the neighborhood of the 10v of reads now before any of those upgrades. It is not the load of those upgrades pulling voltage down on that circuit, if that's what you're suggesting.
 
When I jump the blue alt/VR lead to batt + with the engine idling at 900 RPM, batt V jumps to 13.7. As for load from the EFI, fuel pump, and HEI, IGN 1 output was in the neighborhood of the 10v of reads now before any of those upgrades. It is not the load of those upgrades pulling voltage down on that circuit, if that's what you're suggesting.
You have proven your alternator works fine, your VR works fine, your wiring is good EXCEPT for the feed from the ignition switch.

If a wire and connectors are properly sized and the connections are good, clean and tight there will not be a voltage drop for whatever load you put on it. Trunk mounted batteries use HUGE gauge wires because if they dont they loose too much voltage to heat and you can't start the car.

NOW if the wire is under sized for, lets say a 10 amp load, you can expect a voltage drop because as the load increases the resistance of the undersized wire also increases, as the resistance increases you loose voltage to heat in the wire till you melt the wire.

Now lets say the wire is properly sized but you have bad connections, they create resistance and creates a voltage drop and that voltage drop creates heat and the plastic insulator starts to melt.

I'm not being a jerk here and you have diagnosed your problem excellently. BUT... you seem adverse to tracking down your voltage drop. It is the source of your problem. You can bypass the ignition switch and associated wiring with a relay BUT you still have a voltage drop problem.


lastly you say IGN 1 had a 2+V drop BEFORE you added additional loads, IF IGN 1 is feeding those additional loads that is only adding fuel to the fire.
 
Yes. Weird. You may have more problems than you think. Have you, when it's running "fast idle" and should be charging, have you compared battery voltage to the alternator stud? Maybe there's a bad connection in the charge/ ammeter circuit

EDIT Sorry I missed the addtional posts

I agree with Dana. I would darn sure get the "run" ign1 voltage drop problem fixed and go from there.

EG if additional load current is limiting field current, the thing may not keep up regardless of what the VR is trying to do, and that might explain why you conclude that you have two bad ones.

Just for drill I am 77. I first got into helping guys (fellow sailors, NAS Miramar, San Diego,) in about 1970 I was a Navy ET and maintained GCA RADAR and TACAN. I found my very first broked "welded splice" (the main one in the black ammeter circuit) in a friend's 68 RR about 1972. Hell I had never SEEN a welded splice before then.

My 70 440-6 RR ate the ammeter and damaged the bulkhead ammeter terminals, back then, as well. Al Gore had not invented the internet, yet.

If you know anything about amateur radio, I had a GE "pre prog" vacuum tube UHF receiver and GE TPL 80 watt 2 meter (VHF) rig in the car, and for a short time, the unique and fussy SBE 33 HF transceiver.

sbe_sb33.jpg
sbe_sb33.jpg


I cannot pull the name of the antenna out of my mind, but I can picture it. It was a completely tuneable HF antenna, with a long loading coil. You tuned it by pulling the whip up and down until it was resonant, and without the test equipment we have nowadays, it was a REAL PITA

sbe_sb33.jpg
 
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Have you checked for corrosion on/in the coil negative? Also bulk head connector. Ammeter is third guess and that's all I've got.
 
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Yes. Weird. You may have more problems than you think. Have you, when it's running "fast idle" and should be charging, have you compared battery voltage to the alternator stud? Maybe there's a bad connection in the charge/ ammeter circuit

EDIT Sorry I missed the addtional posts

I agree with Dana. I would darn sure get the "run" ign1 voltage drop problem fixed and go from there.

EG if additional load current is limiting field current, the thing may not keep up regardless of what the VR is trying to do, and that might explain why you conclude that you have two bad ones.

Just for drill I am 77. I first got into helping guys (fellow sailors, NAS Miramar, San Diego,) in about 1970 I was a Navy ET and maintained GCA RADAR and TACAN. I found my very first broked "welded splice" (the main one in the black ammeter circuit) in a friend's 68 RR about 1972. Hell I had never SEEN a welded splice before then.

My 70 440-6 RR ate the ammeter and damaged the bulkhead ammeter terminals, back then, as well. Al Gore had not invented the internet, yet.

If you know anything about amateur radio, I had a GE "pre prog" vacuum tube UHF receiver and GE TPL 80 watt 2 meter (VHF) rig in the car, and for a short time, the unique and fussy SBE 33 HF transceiver.

sbe_sb33.jpg
sbe_sb33.jpg


I cannot pull the name of the antenna out of my mind, but I can picture it. It was a completely tuneable HF antenna, with a long loading coil. You tuned it by pulling the whip up and down until it was resonant, and without the test equipment we have nowadays, it was a REAL PITA

View attachment 1716426597

GRA-750B ?​

 
No what I had was from the '50's or 60's. I KNOW the name, and can picture it. Very long sender loading coil from the mount. Had a collet and nut arangement on the whip to pull it out and tighten. Had a spring "donut" wound on a little form, that made contact, inside the loading coil. It was light blue.

Later on in the 90's working for the Motorola shop, I had a "screwdriver" antenna, named because the originals were tuned by a B&D electric screwdriver motor, run to a toggle switch up front. I also had what is called a Metron mobil amp. Those things are bulletproof, about 600W peak output on SSB The cruise control on my 87 Ranger did not like it!!!

I had a number of transceivers, including an Alinco something DX70?, a Kenwood TS-50, a Yaesu FT-757DXII, and an FT 890. All of these were a PITA because of delicate, multi function controls which made controlling them, specialy at night, difficult. The BEST mobile was an Icom IC735, which has much easier to deal with controls. In fact I JUST BOUGHT 2 more 735's (after the house fire) which makes them about the 5th and 6th I've owned.
 
Yes. Weird. You may have more problems than you think. Have you, when it's running "fast idle" and should be charging, have you compared battery voltage to the alternator stud? Maybe there's a bad connection in the charge/ ammeter circuit

EDIT Sorry I missed the addtional posts

I agree with Dana. I would darn sure get the "run" ign1 voltage drop problem fixed and go from there.

EG if additional load current is limiting field current, the thing may not keep up regardless of what the VR is trying to do, and that might explain why you conclude that you have two bad ones.

Just for drill I am 77. I first got into helping guys (fellow sailors, NAS Miramar, San Diego,) in about 1970 I was a Navy ET and maintained GCA RADAR and TACAN. I found my very first broked "welded splice" (the main one in the black ammeter circuit) in a friend's 68 RR about 1972. Hell I had never SEEN a welded splice before then.

My 70 440-6 RR ate the ammeter and damaged the bulkhead ammeter terminals, back then, as well. Al Gore had not invented the internet, yet.

If you know anything about amateur radio, I had a GE "pre prog" vacuum tube UHF receiver and GE TPL 80 watt 2 meter (VHF) rig in the car, and for a short time, the unique and fussy SBE 33 HF transceiver.

sbe_sb33.jpg
sbe_sb33.jpg


I cannot pull the name of the antenna out of my mind, but I can picture it. It was a completely tuneable HF antenna, with a long loading coil. You tuned it by pulling the whip up and down until it was resonant, and without the test equipment we have nowadays, it was a REAL PITA

View attachment 1716426597
The issue is the switched "12V" (actual 10V) that is connected to the field terminal beyond the shadow of a doubt. Jumping the blue wired field terminal to batt + (either at the batt or the batt post on the alt) increases the batt +to 13.7 V. I have not reinstalled the original VR but it may well be fine.
 
Have you checked for corrosion on/in the coil negative? Also bulk head connector. Ammeter is third guess and that's all I've got.
There is no coil. I added a ground buss and everything that draws a load is grounded to it and the batt. I can unplug and replug the bulkhead connectors, that's a good idea, the resistance on IGN 1 causing the voltage drop could be there, and that's an easy "fix" thanks
 
Yes. Weird. You may have more problems than you think. Have you, when it's running "fast idle" and should be charging, have you compared battery voltage to the alternator stud? Maybe there's a bad connection in the charge/ ammeter circuit

EDIT Sorry I missed the addtional posts

I agree with Dana. I would darn sure get the "run" ign1 voltage drop problem fixed and go from there.

EG if additional load current is limiting field current, the thing may not keep up regardless of what the VR is trying to do, and that might explain why you conclude that you have two bad ones.

Just for drill I am 77. I first got into helping guys (fellow sailors, NAS Miramar, San Diego,) in about 1970 I was a Navy ET and maintained GCA RADAR and TACAN. I found my very first broked "welded splice" (the main one in the black ammeter circuit) in a friend's 68 RR about 1972. Hell I had never SEEN a welded splice before then.

My 70 440-6 RR ate the ammeter and damaged the bulkhead ammeter terminals, back then, as well. Al Gore had not invented the internet, yet.

If you know anything about amateur radio, I had a GE "pre prog" vacuum tube UHF receiver and GE TPL 80 watt 2 meter (VHF) rig in the car, and for a short time, the unique and fussy SBE 33 HF transceiver.

sbe_sb33.jpg
sbe_sb33.jpg


I cannot pull the name of the antenna out of my mind, but I can picture it. It was a completely tuneable HF antenna, with a long loading coil. You tuned it by pulling the whip up and down until it was resonant, and without the test equipment we have nowadays, it was a REAL PITA

View attachment 1716426597
I'm familiar with Ohms Law, wire gauge considerations, etc.
 
Yes. Weird. You may have more problems than you think. Have you, when it's running "fast idle" and should be charging, have you compared battery voltage to the alternator stud? Maybe there's a bad connection in the charge/ ammeter circuit

EDIT Sorry I missed the addtional posts

I agree with Dana. I would darn sure get the "run" ign1 voltage drop problem fixed and go from there.

EG if additional load current is limiting field current, the thing may not keep up regardless of what the VR is trying to do, and that might explain why you conclude that you have two bad ones.

Just for drill I am 77. I first got into helping guys (fellow sailors, NAS Miramar, San Diego,) in about 1970 I was a Navy ET and maintained GCA RADAR and TACAN. I found my very first broked "welded splice" (the main one in the black ammeter circuit) in a friend's 68 RR about 1972. Hell I had never SEEN a welded splice before then.

My 70 440-6 RR ate the ammeter and damaged the bulkhead ammeter terminals, back then, as well. Al Gore had not invented the internet, yet.

If you know anything about amateur radio, I had a GE "pre prog" vacuum tube UHF receiver and GE TPL 80 watt 2 meter (VHF) rig in the car, and for a short time, the unique and fussy SBE 33 HF transceiver.

sbe_sb33.jpg
sbe_sb33.jpg


I cannot pull the name of the antenna out of my mind, but I can picture it. It was a completely tuneable HF antenna, with a long loading coil. You tuned it by pulling the whip up and down until it was resonant, and without the test equipment we have nowadays, it was a REAL PITA

View attachment 1716426597
You've all convinced me I'm going to stop applying band aids and find out why I don't have near batt V on IGN 1 (and possibly IGN 2) even though I REALLY want to drive this around. Thanks for the wake up call.
 
I've posted on this a lot. It can be ANY terminal(s) in the ammeter circuit, the connector at the ign switch, or IN THE SWITCH itself. Once again, the "easy fix" is to install a relay.

In any case of V drop in this situation, often the alternator goes OVER voltage, so it's a "twofer."
 
I've posted on this a lot. It can be ANY terminal(s) in the ammeter circuit, the connector at the ign switch, or IN THE SWITCH itself. Once again, the "easy fix" is to install a relay.

In any case of V drop in this situation, often the alternator goes OVER voltage, so it's a "twofer."
I have a relay, have had it since the 2nd day I owned the car, as I've written here several times. The only areas the IGN 1 circuit powers is the trigger for the relay, and the blue reg/alt wire. The relay trigger draws a fraction of an amp, I don't know how may amps the field winding in the alt draws, but the wire to the field terminal looks like 18G from the factory so I doubt it's more than a few amps. I'll refresh all the connections.

I still don't understand how the ammeter is measuring positive amps when batt V is 12.3 as the engine is at 1000 RPM. The charging is not evident at the battery or at the alt battery post. The batt is not being charged so it's not creating the amperage draw being read by the ammeter.
 
I had some sleep and now sipping coffee, I've never seen a fusable link go bad but have heard of no charge issues from them corroding. .
the fusible link is connected to bulkhead connector 'J', which directly connects the alternator to the ammeter. The fusible link is usually positioned about 6 inches from the bulkhead connector on the firewall side.
The alternator passes the charge to the ammeter first, then through the fusable link then to the battery.
That's why you see no charge at the battery if the link is bad.



amp-ga18.jpg
 
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I had some sleep and now sipping coffee, I've never seen a fusable link go bad but have heard of no charge issues from them corroding. .
the fusible link is connected to bulkhead connector 'J', which directly connects the alternator to the ammeter. The fusible link is usually positioned about 6 inches from the bulkhead connector on the firewall side.
The alternator passes the charge to the ammeter first, then through the fusable link then to the battery.
That's why you see no charge at the battery if the link is bad.



View attachment 1716426796
Thanks.
Fusible link is good.
 
I have a relay, have had it since the 2nd day I owned the car, as I've written here several times. The only areas the IGN 1 circuit powers is the trigger for the relay, and the blue reg/alt wire. The relay trigger draws a fraction of an amp, I don't know how may amps the field winding in the alt draws, but the wire to the field terminal looks like 18G from the factory so I doubt it's more than a few amps. I'll refresh all the connections.

I still don't understand how the ammeter is measuring positive amps when batt V is 12.3 as the engine is at 1000 RPM. The charging is not evident at the battery or at the alt battery post. The batt is not being charged so it's not creating the amperage draw being read by the ammeter.
At one point I was trying to make the point that ALL underhood loads should be powered by your relay.

So far as the ammeter, maybe it's stuck? Or maybe static electricity? Try taking a damn towel, and just barely wiping the cluster face area in front of and around the ammeter and see if the needle moves. The system may also be generating "just enough" to move the needle. You have a multimeter with a 20A scale? Put it at the output of the alternator and see just what it is doing. A safer way would be to "rig" an old stop/ tail lamp filament in series with the alt output to see if it is charging enough to light.
 
At one point I was trying to make the point that ALL underhood loads should be powered by your relay.

So far as the ammeter, maybe it's stuck? Or maybe static electricity? Try taking a damn towel, and just barely wiping the cluster face area in front of and around the ammeter and see if the needle moves. The system may also be generating "just enough" to move the needle. You have a multimeter with a 20A scale? Put it at the output of the alternator and see just what it is doing. A safer way would be to "rig" an old stop/ tail lamp filament in series with the alt output to see if it is charging enough to light.
Well I gave up on trying to determine where the resistance is that's pulling IGN 1 down to 10.5V.
I added my own blue wire to the alt field + and appropriate terminal on the VR, and tied it into batt + on the output side of the relay.
I'll just cross my fingers and carry a fire extinguiser for the time being until the weather is conducive to testing under the dash. I went through the bulkhead connectors, I don't think the poor connection is there.
The ammeter now shows around +40 when the engine is running. It returns to zero when the engine is off.
Drove it around a bit today, runs pretty good, the TB EFI and HEI distributor are working well.
I need to check the ign advance, not sure what the CHINACO HEI distributor is adding, I just set intitial timing to 8 degrees BTDC and moved on. I'm not winding the engine way up anyway, and I'll verify total timing tomorrow.
Biggest issue now is the Z bar is sliding sideways. The ends of the spring clip protruding into the groove in the plastic bushing is not enough to hold the z bar in position. Being as the bushing has just as much tendency to spin in the z bar tube as to spin on the spherical end of the stud, eventually the cut in the bushing will line up with the spring clip, allowing the zbar to move sideways. Being as my car was an automatic, and whomever did the conversion did a shitty job of locating and reinforcing the hole for the body side z bar stud, the z bar is likely loaded sideways, and thus it's tendency to shift. I did not relocate the hole but did reinforce the body enogh to keep the stud from bending opposite the direction of appled force. I'm going to make brass spacers that will hold the z bar side to side.
 
plus 40??? What is the voltage doing?. On an aside, I see no reason NOT to run the VR and field off the relay
 

plus 40??? What is the voltage doing?. On an aside, I see no reason NOT to run the VR and field off the relay
It's in the ballpark, around 14V peak, when I checked last.
Obviously NOT charging the battery at 40A.

I needed switched batt V and that seemed like the best place to get it.
 
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