wiring a voltage regulator

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i installed a wiring harness from american autowire wich is designed to use a 1 wire alt. ive heard bad reviews so i wired in my stock alt and voltage regulator. i cut the plug for the regulator off my old harness and ran the green wire sraight to a field. i took the blue wire and went from the reg to the + side of coil and then to the other field. with this setup i was getting 35 volts at idle, thankfully i checked with my voltmeter before hooking up the alt.

today i disconnected the blue from the + side of coil and went straight to battery and now i'm getting 1.2 volts. ive got good grounds to voltage reg and have tried two seperste regs with same results. anyone have any ideas?
 
you shouldn't be running either of those field wires directly to the coil !?!

are you using a ballast resistor?
 

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no, i do not have a ballast resistor. the reason i used the coil is it was the closest 12v keyed source
 
You have to be sure of several basic points

1---That the point you hook the regulator blue (and the second field connection) to is ACTUALLY close to battery voltage because this is not only power for the regulator, but your "voltage sense."

So to check that, with "things" hooked up as per normal/ ready to run, turn your key to "run" but with engine off. Hook one probe of your meter directly to battery positive, and the other to a point as close as you can get to the regulator IGN (blue) connection, IE your coil + with no ballast

What you are doing here is directly measuring the voltage drop between the battery, all the harness/ connectors/ switch/ etc to the regulator. If you have the second field hooked to the same point as the regulator blue wire, hook up to the blue field connection. Make sure everything is hooked up, as you want the "normal" load on this circuit.

You are hoping for a very low voltage, the lower the better. Over .2V (two tenths of one volt) means you have a bad connection or bad switch somewhere.

2---Make sure the second alternator field terminal is also hooked to switched 12V

3---Make ABSOLUTELY sure that the regulator is actually grounded. You can operationally check this once you get the system running. To do that (after you find/ fix the problem) run the engine at "medium cruise" RPM, and run this check with NO loads turned on, and again with as much "stuff" as you can bring online, IE lights, heater, etc.

Hook one probe of your meter directly to the battery NEG post, and the other probe to the CASE of the regulator. Be sure to stab through any rust, chrome, etc.

Once again, you are hoping for a very low voltage, the lower the better. Zero is perfect, and once again, over .2V means you have a ground problem.

Your battery up front or in the trunk? Make SURE the block, the body, and the battery NEG are all securely grounded. On a front--mount battery, which is grounded to the block, I like to run a 1 ft starter (ring to ring) cable from a bolt on the rear of the driver side head over to the firewall, master cylinder bolt, etc.

Install star washers under the regulator mount bolts, they must be tight and not stripped. Scrape the firewall clean around the mount.

Pull your regulator connector and inspect the pins of the regulator and inside the connector. Push on/ off the connector to scrub the terminals clean and to check for tightness

4---Where are you checking this 35 volts? At the alternator output? It might just be that the alternator is NOT actually connected to the battery. Not knowing the details of your harness, how it's wired, or what might have happened, it might have a mis-wiring problem, a popped fuse link, etc.

==========================================================================

I didn't bother to check, is the documentation for these harnesses online, and if so can you post a link?
 
wow 67dart, thank you for spending the time for that reply. i love this site.
the one thing that you mentioned that caught my attention is '' make sure second field terminal is also hooked to 12v''. i wired my 2nd field (green) straight to my voltage reg.
 
LOL. When I said second I meant "other than green" as you'd mentioned you'd run the green wire. So looking at the diagrams above, you need

1-either one of the field terminals (green) run to regulator

2-The remaining field run to switched 12V

Does not matter which is which HOWEVER be CERTAIN to check that NEITHER field terminal goes to ground

There were two members here recently who got "parts store rebuilds" both of which incorrectly had a grounded field. This can occur for several reasons:

One field terminal can be damaged or missing the insulating washer under the screw, grounding the field

Or the alternator can be a "rebuilders nightmare" which is an early (69) which was drilled by the rebuilder to accept an aftermarket insulated brush. If this is improperly installed, OR the original grounded brush is ALSO installed the field, again, will be grounded.

If you are unlucky enough to hook your blue switched ignition to that wire, bad things happen.

Otherwise, the damn thing simply charges "full tilt."
 
well i don't know what i done but it's working. i hooked the vr straight to + side of battery instead of the coil and i also ran a ground from battery to vr. it worked like a charm so i removed the extra ground from battery, still worked, so i unhooked it from the battery and back to the coil and it's working. don't know but i'm not gonna argue. thanks for the help.
 
I have a really bad problem with the alternator it putting out 18-20V on idle which the voltage regulator should regulate. The battery is fully charged and does not running anything that demands any electricity. I have drawn the cable as the 73 Dart wiring diagram. But I read what 73AbodEE said and the field should not be connected with the coil which the 73 wiring diagram shows you should. I have drawn the cables like the 73 wiring diagram in the picture. I connected like 73AbodEE showed in his chart but the car didn't start then. Have tried everything please give me some input how I can go from here. Is a Dart 73, 318 with electronic igniton. Thanks

 
Pompis that wiring diagram you posted is WRONG. Look at the one 73A posted earlier above. Notice that the IGN terminal of the regulator is hooked to the end of the ballast that is jumpered together, NOT the coil end.

Incidently, if you have a 4 terminal ballast, pay attention to the drawing RE: the "U" shaped cutout in the ceramic base, which properly orients the two sections of the resistor assembly.

In the diagram posted earlier, that "upside down U" is at the bottom of the ballast.

If your review some of my posts regarding voltage drop, the two biggest causes of overcharging is voltage drop in the regulator IGN terminal circuit, IE giving the regulator LOW voltage, as well as a poor ground between the battery and the regulator case
 
67Dart273 said:
Incidently, if you have a 4 terminal ballast, pay attention to the drawing RE: the "U" shaped cutout in the ceramic base, which properly orients the two sections of the resistor assembly.
Click to expand...
Great catch 67Dart273. Actually, the diagram shows the "I" terminal wired both upstream and downstream of the ignition ballast, which would short it out. No wonder so many people get confused and perhaps some cars are wired wrong and over-charging and others experience melted ECU's (where did diagram originate?). To verify that a dual ballast is wired correctly, one should measure 5 ohms from the upstream side of the ballast to the 5th pin of the ignition box and 0.5 ohm from upstream side to coil+. The upstream side is the side with the "U" where the terminals are connected together (Dk Blue from IGN1 on key switch). More modern ignitions lose the ballast confusion, but simplest to run with what you got and many like to stay original.
 
I am no pro at wiring but i just did a painless kit in my dart. the voltage reg. was super easy on mine. i had only 1 wire from the harness that went to the field wire on the alt. this wire was a designated wire right out of my fuse box. that is my voltage signal wire. then i had the two wires from the voltage reg that went to both field wires and only those wires. you must make sure your voltage reg. is grounded very well.
 
very nice explanation, Dart273. I stole your wiring diagrams for my use in class. Teaching charging systems to a bunch of old hot rod students.
 

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