67 Barracuda Heavy Electric Load

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Here are a couple picks of the radiator/fan.

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DallasMan2000 said:
So the needle went slightly towards the D when the car started then quickly moved back to the middle. I also measured 12.17 volts at the alternator post once the car started.
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That does not sound like an ammeter. Right after start up with an ammeter the needle should head toward C as the system recharges the battery. Either the gauge has been converted to a voltmeter, or the alternator is not charging to recuperate the system after the drain to spin the motor.
 
str12-340 said:
That does not sound like an ammeter. Right after start up with an ammeter the needle should head toward C as the system recharges the battery. Either the gauge has been converted to a voltmeter, or the alternator is not charging to recuperate the system after the drain to spin the motor.
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Its an ammeter. A Voltmeter would be 0 with the the engine off.
Unfortunately, its not isolated to just a battery any more. So now the current path is a muddle and the ammeter isn't showing flow from or to the battery.
 
Mattax said:
Its an ammeter. A Voltmeter would be 0 with the the engine off.
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Unless it's wired to a source that is always hot. You could disconnect the battery and see if the needle stays in the middle or drops toward D, right?

I think that I would disconnect the power wires related to the fan set up and then see how the ammeter reacts. I think that would tell you if it was the fan wiring that was causing the issues.

I can't understand that there is a hot wire from the battery terminal AND a hot wire from the starter relay all headed for the fan...
 
67Dart273 said:
Most of them did not have large alternators, either, and some of the big ones had the factory bypass, known as the Police/ Fleet / Taxi wiring.

My 70 440-6 RR managed to "eat" the bulkhead terminals way way back about 1973 or so. Of course Al Gore had not invented the internet, yet, so I drilled out the wire holes in the connector and doubled up some larger gauge wire and fed through there. I also SOLDERED THE STUD CONNECTIONS in the ammeter, (to the shunt) which very interestingly, is documented by someone else in "today's" generation.

I've seen at least a dozen pickups with melted ammeters which had had such things as driving lights and or winches added. Another "biggie" was snow plow hoists, which were operated by large electric motors.
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You mean there are people out there ignorant enough to wire in a winch, snow plow or other high amp draw THROUGH the factory amp gauge wiring? Even "I" would wire something like that in COMPLETELY SEPARATE from the rest of the system.
 
OK. This doesn't get to the problem, but at least now we can draw a diagram of some of what is on the car.
There still is the mystery wires going in with the speedometer cable.

The reason the ammeter isn't showing charge after starting.
As discussed early, electrons flow through the back of the ammeter when the battery is charging like this.
The ammeter needle deflects (by magnetism) to show the flow.
1704333394596.png


But in this case the current is flowing the other way, because the battery is powering the ignition, and presumably nothing else.


1704424905208.png

Additionally with this wiring when the fan turns on and the alternator is not working, battery power to the fan will not show as discharging on the ammeter.
When the alternator is working, current to charge the battery will bypass the ammeter. The new wire to the stud on the starter relay is the shortest path.

The fan must be connected to the fan relay. Its a heavy red wire at the fan.
[edit below speculation was bassed on the understanding of two hots to the relay. reviewing the photos there is only one relay on the firewall]
One explanation for two hots to the relay is that there are actually two relays. Maybe one for headlights.
Another possibility is that one of those hots goes to the temperature switch and then is the trigger.
But more likely that comes from a key on circuit, such as J2 (which as noted in the previous thread was damaged).

The wire from the alternator output stud to the battery ought to have a fuse or a fusible link.

Here's a stock '67 with an later ECU. Modify this one in MS Paint or IRFANview to whatever you discover.
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str12-340 said:
Unless it's wired to a source that is always hot. You could disconnect the battery and see if the needle stays in the middle or drops toward D, right?

I think that I would disconnect the power wires related to the fan set up and then see how the ammeter reacts. I think that would tell you if it was the fan wiring that was causing the issues.

I can't understand that there is a hot wire from the battery terminal AND a hot wire from the starter relay all headed for the fan...
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I agree. I gave it my best shot in the post above. Tommorrow is a long day so gotta sign off.
 
RustyRatRod said:
You mean there are people out there ignorant enough to wire in a winch, snow plow or other high amp draw THROUGH the factory amp gauge wiring? Even "I" would wire something like that in COMPLETELY SEPARATE from the rest of the system.
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It is or was common to wire an electric winch or a plow to the battery. Many of them need the power (amps) that only the battery can provide. If wired to the alternator, battery power would have had been drawn through the ammeter and its wires anyway. Definately a better thought out system was needed for sustained high current equipment. At minimum heavier duty wiring, meter and connections, and a bigger battery.
 
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RustyRatRod said:
You mean there are people out there ignorant enough to wire in a winch, snow plow or other high amp draw THROUGH the factory amp gauge wiring? Even "I" would wire something like that in COMPLETELY SEPARATE from the rest of the system.
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"Through the ammeter" is not how they are wired, but they put so much load on the charging system that they damage the charge wire, bulkhead connector, and ammeter--just like on A bodies and just like we are talking here (likely). I've said before, my old 70 RR ate the bulkhead connector and damaged the ammeter way back i the early 70's. And it didn't have a winch, lolol
 
I just hope its the Alt. to bad you didn't bypass the Regulator 1st just to see the output.
 
DallasMan2000 said:
These is a lot going on at the starter relay - see pic below. The large black wire coming in to the top comes directly from the alternator post.

View attachment 1716187478
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How does it get to the battery, AKA how large is it? Photos can be "skewed" but I see nothing there except for the one you mentioned, that looks very heavy
 
Thanks again for all the info. Auto Electric still had not looked at the alternator when I called them this afternoon. They said maybe tomorrow morning. I will go back over these posts carefully this weekend.
 
I like puzzles and have a few minutes to look at this again.
Here's what the wires in the photos seem to be.
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The black wire with the other in-line fuse - I don't know where that goes.
But it only makes sense that the relay is feeding the red wire going past the battery and onto the fan.
The relay we see on the firewall only has 4 wires. So that's just one relay. If there is one for the headlights, its somewhere else.
I'm going to guess the other red wire is M&H replacement harness continuation of the battery circuit A1B. It should go the fusible link and connect through at position Z on the firewall.

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ECU with factory auxillery ballast and wiring for an isolated field alternator and regulator. Apparently this is what M&H supplied.
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Auto Electric Systems Inc in Dallas just got back with me on the alternator. They said the alternator does not put out enough charge at an idle, but it can get up to 80 amps at high rpm’s. He asked for pictures of the mounting area (I just provided) and he is going to quote me for a new alternator that they will put together that will produce adequate charge at an idle.

Am I asking the right questions and does this seem reasonable?
 
Okay, it been a while but still chasing this issue. Dallas Auto Electric says I need a different type of alternator that puts out more at lower RPMs. According this the shop, the alternator I took to them is a high output alternator but only at higher RPMs.

So the recommendation from them is that they build a new alternator for $300 but I need to get a new / custom mounting bracket. They are going to get me details on the bracket. I also asked if the new proposed alternator would put out too much at high RPMs and they said no.

Does this sound like a reasonable/plausible solution?
 
$300? I paid about half that for one of the late '80s / early '90s 318 alternators. Just tossing out another option.
 
I had a High Output alternator on my car once, discharged at idle, like maybe good for a drag car, seemed totally useless to me. I believe it was a Power Master totally useless part. I bought a round back alternator from Autozone or somewhere been good for 15 years now.

I run ground wire from voltage regulator to the coil bracket bolt on intake manifold. Make sure a ground wire runs from back of head to firewall too. When I used to run mopar electronic ignition I also ground that to engine

I did notice if I unplug bulkhead then plug it back together I have to go under dash and push in and seat one of those fat amp wires cause they get pushed in a tad creating a loose connection. Check verify dont assume.

I still have stock wiring no issues yet. But the improved wiring mods sound like in my future.

Clutch fan with shroud works fine for me. No way I would run electric fans without all the wiring mods, volt meter, headlight relays etc.

I recently had some bozo with a ratty old chevy truck at car show tell me 'you need electric fans your loosing power'? Yeah sure I can make you invisible with a cloud of tire smoke with my loosing power car ok.
 
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