Battery Draining on '66 Bronco - Voltage Regulator question

When I first bought the '66 I replaced the battery immediately and had the alternator checked out as well (not ruling out the alternator yet), after that she fired up no problem. Yesterday my fiance drove it to work and it died on her when she was getting ready to leave. We just pulled the voltage regulator which I believe to be the problem but noticed one of the original wires is cut and there's a ceramic cylinder looking think I've never seen before. Any help as to what the ceramic cylinder thing is? And do I need to hook up the 5th wire for the voltage regulator?

BroncKrawler said:

When I first bought the '66 I replaced the battery immediately and had the alternator checked out as well (not ruling out the alternator yet), after that she fired up no problem. Yesterday my fiance drove it to work and it died on her when she was getting ready to leave. We just pulled the voltage regulator which I believe to be the problem but noticed one of the original wires is cut and there's a ceramic cylinder looking think I've never seen before. Any help as to what the ceramic cylinder thing is? And do I need to hook up the 5th wire for the voltage regulator?

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Don't know what that 5th wire would be. It doesn't show in the schematics.

http://public.wsu.edu/~i6735189/66_71el1.gif

That ceramic cylinder looking thing is a capacitor. It's actually a metal can that appears to be covered in dirt... It attached in the connector to the same place at the other yellow wire (152) that senses the voltage. There's an orange wire (35) that goes to the Field connection on the alternator to turn it on. And there should be a Red w/Green stripe wire (904) that supplies power to the voltage regulator.

There is a black w/ red stripe ground wire (26) that comes through the harness and usually is loose and attaches to one of the VR mounting screws. It might be that wire, but I've never seen it on the connector.

Steve's got it. The 5th wire you see in some diagrams is ONLY for Ford cars and trucks that use a charge indicator light on the dash. Any Ford of our vintage that has an ammeter (like our EB's do) only has the 4 wires in three positions.
If you can see the letters listed on yours still, they go "FSAI" in that order.
"F" is the Orange field wire mentioned.
"S" is the Green w/red (?) wire. I like to think of it as "S for Switched" to remember it's only on with the key.
"A" is the two Yellow wires that are "Always" powered.

The Black w/red wire that Steve mentioned should be there somewhere. If not, you need to make your own to run between the alternator and a regulator mounting screw so that they are always at the same ground potential. After all, Broncos don't ground well...

Always make sure your regulator is mounted to the body before connecting the power to it. You can damage it if it's un-grounded when power is applied.
You can leave the capacitor (radio noise suppressor) disconnected temporarily while testing. They can go bad and cause a little mischief when trying to track down issues.

You should clearly see your ammeter go up and down as the engine is running and things are turned on and off. If it never goes up, but only reads in the negative range, or zero, then you're not charging yet and still have to find a problem.

Paul

There is no black wire w/ red stripe grounded at the VR or at the Alternator, so I ran a ground wire and still no luck. I thought I stumbled onto the problem when I noticed the Orange wire (35) was a very loose connection so I rewired that as well but I still can't get the ammeter to show it's charging while running. I'm going to take the alternator back in today and have them check it out. I appreciate the help and that wiring schematic is great to have!!

The more I dig, the deeper I realize the wiring is so far gone it'd probably be better to just get a Centech harness like I did with my '68... the good ol' snowball effect has once again started with this Bronco %)

Disconnect the regulator connector. Then jump the orange wire to the yellow wire. This will bypass the regulator and put the alternator into a full charge mode. If it charges then the alternator is good and regulator is bad. If it still doesn't charge the alternator is bad.

I was hoping you would post up Viperwolf! If I hadn't torn most of the wiring apart getting to the root of my problems I would try what you mentioned above. I dropped the alternator off at Napa to have them check it a little bit ago and it tested fine, we did swap in a new VR today but I've learned even new parts can be bad already. Any clue as to what this box is next to my coil? The previous owner has spliced into the wiring harness for this box and it goes to the distributor so it's some sort of electrical module, what it is I have no clue. I'm thinking it could be part of my problem though... Then the mystery continues under the dash, where the stock fuse panel has no fuses except for a piece of copper that was trimmed to fit in the fuse location for the turn signal 14A fuse. Behind the ignition switch are 3 wires tapped into the post that would normally power the heater, radio, and windshield wipers if I'm not mistaken. And what are the little rectangle boxes screwed the bottom side of the dash with wires running to them?

First one is a Duraspark ignition control module. Since your engine is running, it's either working or not part of the system.

The thingy under the dash looks like a circuit-breaker. Might be protecting that circuit that's jumped in the fuse box, but it might not be too. Can't know until you trace things to their origins and ends.
That's quite the mish-mash of stuff ain't it? Kind of gives power-distribution a whole new look.

Paul

DirtDonk said:

First one is a Duraspark ignition control module. Since your engine is running, it's either working or not part of the system.

The thingy under the dash looks like a circuit-breaker. Might be protecting that circuit that's jumped in the fuse box, but it might not be too. Can't know until you trace things to their origins and ends.
That's quite the mish-mash of stuff ain't it? Kind of gives power-distribution a whole new look.

Paul

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There's so much wrong on this Bronco it amazes me, but I guess that explains why I got such a good deal on it. A similar scenario happened on my '68 with the stock wiring, and after doing a Centech harness swap on it I haven't had a single issue for over 4 years. This is my soon to be wife's '66 and she wants to drive it daily to work during the summer days so I've gotta fix things right! I don't know much about the duraspark setup but I would prefer to go back to a standard ignition setup with a DUI distributor and some 8mm Livewires when I'm done with it.