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Sudden Engine Die, Rough Idle Carb'ed 351

DirtDonk

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What color is the other wire on the small terminal of the starter solenoid? It’s possible that your brown with black is just dirty, or it could be a very old and faded Red with a blue stripe.
If it’s the red with a blue stripe then it belongs on the S terminal, but if it’s brown and happens to have some sticky black gunk on it, it belongs on the I terminal.
You really need a voltmeter to test all the stuff and should be using it constantly. When the engine is running, the battery should read approximately 14 1/2 V.
When it’s not running it should read 12.6 or thereabouts.

You should test the two small wires.
The brown one should have 6 to 12 V any time the key is in the on position and the red with blue should have 12 V when the key is in the start position only.
 
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TX-ZACH

TX-ZACH

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Chappell Hill Texas
I cant 14v off of anything. Other wire on S appears to be black/red. The wrapped on wire is HEI harness. The disconnected wire appears to be blk/yellow. Here is a close up of that disconnected wire.
 

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DirtDonk

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Your ammeter remains at zero and your battery is dying and you’re not reading 14V anywhere because the alternator is not charging.
Of course we don’t know yet why that is because there are still tests to perform.

What is that huge wire doing on the I terminal of the starter relay? Multiple wires bundled together?
If so, what are they?
 
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TX-ZACH

TX-ZACH

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That wrapped wire is the HEI wire connecting to harness at dizzy with braided loom. Here are a couple of pics of the alternator. No wiring has been changed or replaced. I drove it up to O'Reilys and had them test the alternator. Their guy said the system was surging and pointed me to another voltage regulator. I have tried (2) new regulators and no change. I put the original motorcraft back on. Voltage is reading 12.5v on Alternator while running.
 

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DirtDonk

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Maybe you said already, but what are the two wires on the battery post of the alternator?
There is normally only one wire.
 

DirtDonk

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And when you say HEI, is this the big distributor based on the old Chevy set up? Or is it just a high energy ignition of some other type.
Sorry I’m trying to catch up I should re-read to see if you’re using something different.
But if it’s an HEI style, then there is no reason I can think of for you to be taking power from the I wire of the starter relay.
What does that wire do? Power the distributor?
 
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TX-ZACH

TX-ZACH

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Thought I would try for help one more time before I yank everything and start from scratch or take it to a shop to figure out. The red/green was replaced to coil from ignition to get fire, all good. Reading back over many posts the regulator should be.

3. The regulator should have only three positions of the connector filled. The "I" position is blank on ours and only the "F" the "S" and the "A" positions have wires.
The F is the field wire and is Orange. It runs straight to the FLD terminal on the back of the alternator.
The S is supposed to be the Green w/red wire and is hot with the key in ON only.
The A is usually two separate Yellow wires. One is powered hot all the time and is your sensing wire. The other is a short bit that runs to a radio noise suppressor that is bolted to the side of the regulator.


My regulator harness never had a red/green to "S" but a yellow/red. Maybe I do not have a stock harness or a variation of some sort. When I put a voltage meter on "S" it looks like about 6v. Im thing of splicing new key hot to regulator. Plus my orange wire on "F" is going to green wire plug on alternator. Maybe I do not have ground to alternator either. I never changed any of this stuff prior and seems in working order.
 

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DirtDonk

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Yours is correct. The wire colors have faded.
The one for the regulator is not Red w/green, but instead is Green w/red just as you show in your picture.
It's the middle one and has simply changed color over the last 50 years or so.

The thick one on the left is "Orange" if you squint and cross your eyes just right.

The two on the right are in fact Yellow and so everything you quoted above should be measureable/checkable.
With a volt-meter check for power on the connector where the two Yellow wires are. Should be as close to battery voltage as possible. Very close.
With the key ON you should see 12v on the middle Green w/red wire.
Maybe you can test the Field wire with the OHM setting on your meter. Just to make sure it's still intact between this connector at the regulator, down to the F post of the alternator.

Paul
 
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TX-ZACH

TX-ZACH

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I removed the alternator and had it tested. Its good. Re-installed and added a ground. I spliced that hot for the regulator with the new wire going to dizzy and is now at 14.5 and charging. Amp meter still no go but I can live with that. While putting the alternator in I busted the over-flow nipple off the radiator. ^%$### !!!!
 

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DirtDonk

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Ugh. Hate it when that happens.
But if you still have a local radiator business that hasn't gone out of business (yet!) they can fix it in a jiffy. Or quicker...
You could solder it yourself if you have the stuff, or even epoxy it or something like that. But they can do it easily while you wait usually.

Which "hot" wire from the regulator did you use for the distributor? Hopefully the Green w/red one?

Paul
 

DirtDonk

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Did you ever answer somewhere what kind of HEI distributor you are using? There are certainly better wires to pull from than the voltage regulator, but it might work in a pinch.

Paul
 
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TX-ZACH

TX-ZACH

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Yes sir. That was one of the original problems. I abandoned the ignition wire with the ballast and ran a new one from switch. I did not know the regulator also uses the wire and spliced in. HEI, Chevy style. Id have to research again what it does but it needs to be there to operate. It goes to the wire harness at cap. No start if removed totally dead. I have got to figure out a way to tighten all the belts by myself. I am struggling to get rid of the squeal. Ill try to find a shop or get some soldering tools.
 

DirtDonk

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Yeah, the two wires come off of the ignition switch at the same terminal, but split right there into the Red w/green (ignition resistor) and Green w/red (voltage regulator).
The resistor wire under the dash is pinkish/brownish/uglyish but turns to Red w/green up at the firewall and inside the engine compartment. But still has the lower voltage of the resistor.
Some year Broncos showed Red w/green for a few inches at the ignition switch, but some also ran that brownish resistor wire right up to the switch.

I think someone mentioned that you can use that old Red w/green wire to power up a relay in order to get the full 12v to the distributor. But hey, it works now and that's great.
Hopefully it does not put any undue weirdness into the voltage regulator, but your recent reading of 14.5v is right on the money!
So all good for now. Congrats.

Paul
 
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