Flickering head lights, what am I missing

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67Dart273 said:
The FIRST thing I'd do is upgrade that 18 ga wire in the field/ regulator circuit. One thing you need to realize is that the VR/ field circuit PULSATES and one reason it is not normally noticeable is that the inductance of the alternator field itself sort of averages that out. However, with a long run of too-small wire, you can set up interesting feedback/ oscillations type of deal. The VR power (IGN) terminal MUST "see" "same as battery" to regulate correctly that IS the sensing terminal.

In fact, I see no reason to wire it the way that you did. If you use the small terminals of a 4 terminal (double pole) disconnect to control a relay in conjunction with an ignition switch, you can then pull power for ignition/ field / regulator off the large main feed "up front" and eliminate voltage drop problems
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not an expert by any means , but the first 2 things I thot were 18 ga. too small , and grounds .
 
I went after that long small gauge alternator field wire that I had hooked to the disconnect.
I wired in an under hood relay that provides the field current to the alternator. It is triggered off the ignition wiring that triggers the fuel pump relay, MSD box, ,,,
All the flickering is absolutely gone.
I did not want to mention it earlier to not confuse the issue but I had installed a volt meter in place of the OE Amp meter and that voltmeter was twitching like crazy. I though possibly I had a wonky VM, but no it was also signaling a problem.
All the lights are rock solid now, and so is the VM.
Much Thanks

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Good goin!! Not pickin' on you at all, not at all

This thread is a great example of just how bad a voltage drop situation can be, and some of the "stuff" that can go on. The more electronics envolved, the more important stuff like this is.
 
OK,, the flickering is resolved, the current flow is much more stable, however with the engine running, the rear bumper mounted disconnect no longer kills the engine.
The motor continues to run with the battery disconnect switched to off.
I believe that is because, the way it is wired now the out put from the alternator feeds directly to the field wire and keeps it hot.

If I revert back to the original wiring scheme where I have the alternator field wire running the length of the car back to the rear bumper mounted 4 post disconnect switch, what gauge wire is recommended?
and / or
I am open to other solutions
Thanks
 
OK you are only showing 3 terminals on the disconnect. Can you detail how you have it wired now. I recommend some sort of relay switched by the (normally 2 smaller) disconnect terminals. You can use that relay to break ignition, or 12V feed to the VR, or in case of EFI the fuel pump relay. Or even a combo of 2 or all 3 of those. Obviously a carbureted engine, it would run for a time on what is in the bowl
 
Mattax said:
I think the easiest might be to run a wire from the relay '86' to the Master disconnect.
Use the other terminal on that pair for the ground.
That's something like what was discussed here:
questions about battery disconnect wiring
Click to expand...
Mattax, I have terminal 86 as the ground on the relay,,, are you saying switch the relay ground off with the small disconnect terminals, I can try that.
 
67Dart273 said:
OK you are only showing 3 terminals on the disconnect. Can you detail how you have it wired now. I recommend some sort of relay switched by the (normally 2 smaller) disconnect terminals. You can use that relay to break ignition, or 12V feed to the VR, or in case of EFI the fuel pump relay. Or even a combo of 2 or all 3 of those. Obviously a carbureted engine, it would run for a time on what is in the bowl
Click to expand...
How it is wired now is in post 27,
The disconnect is using the two large terminals.
 
my68barracuda said:
How it is wired now is in post 27,
The disconnect is using the two large terminals.
Click to expand...
I'm sorry that makes no sense. The diagram shows 3 terminals. Doesn't the disconnect have 2 large and 2 small?
 
67Dart273 said:
I'm sorry that makes no sense The diagram shows 3 terminals. Doesn't the disconnect have 2 large and 2 small?
Click to expand...
The round item on the drawing with 3 terminals is the alternator.
You are correct my disconnect has 2 large and 2 small terminals.
The disconnect is shown on the far left of the drawing and I am using two terminals, one in and one out.
 
Here's the deal. I can't read your eff'n diagram, it's too damn small. So sorry, I FINALLY downloaded it and blew it up. Now I see LOLOL You MUST use the two small terminals on the disconnect, and wire them to break something to either stop igntion or stop the alternator from charging.

What does the so called "power module relay cluster" do?

Looks to me like you need to break no 85 to the relay and wire it back to the two small disconnect terminals.
 
There are only two basic ways to get a disconnect to kill the engine. If you use a 2 post disconnect, you must run a great big separate charging wire from the alternator back direct to the battery. But THAT is what all the controversy is about, because it leaves a great big wire to the battery!!! And can defeat the purpose in a crash

The second way is to use a 4 terminal disconnect and break some circuit that will either kill the engine or drop the alternator VR / field so it won't charge. Then the engine will stop
 
Simulated interrupting the relay ground, the 86 terminal.
I disconnected the relay ground from the existing ground terminal then added in a alligator clip jumper to re make the connection.
Started the motor and moved the rear bumper mounted battery disconnect to Off, the engine continued to run, I then removed one end of the temporary alligator clip jumper and the motor immediately died.
So that will work,
Thanks
I will run the alternator field relay ground wire to one small terminal on the disconnect and connect the second small terminal to a good ground.
Question ?
Should I have a fuse on the ground wire? Either on the long run from the under hood relay to the rear bumper disconnect or on the shorter run of the disconnect to the ground?
 
It sure would not hurt. It is actually disturbing how "under" fused the old girls were.
 
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