ALTERNATOR NOT CHARGING BATTERY PLEASE HELP

[57fordf100]

i have a 57 ford f100 with a alternator not generator i connected everything right but the 2 wires that go from the alternator to the regulator there is no power the alternator is good and the regulator is good please help

[Dragon]

Two different wiring styles The ground wire must be present on the Alternator and the Voltage regulator.

Alternator with Meter.jpg

Alternator with Light.jpg

[57fordf100]

k so what i did was run a wire from the ground part of the alternator and i ran it to the regulator like were the 2 bolts are it seems to be working the truck hasent died yet but i may be wrong

[57fordf100]

i forgot to add the 2 wires that are going from the alternator to the regulator not the battery or ground have no power

[Thunderfoot]

Have you got a "resistive" power wire from the ignition switch to the Regulator (either the "I" or "S" terminal depending on how you have it wired)? It sounds like the regulator is not turning on to start the alternator charging. If there is no voltage on the (F)ield wire the alternator will not start charging.

[Dragon]

What resistive wire?
The indicator light has a parallel(to the light) 15 Ohm resistor to help pull in the indicator relay as the bulb does not draw enough current.

The I terminal is for indicator lights. The S terminal is not used in Gauges but is still in the harness as is the I wire which is not used.

[Thunderfoot]

What resistive wire?
The indicator light has a parallel(to the light) 15 Ohm resistor to help pull in the indicator relay as the bulb does not draw enough current.

The I terminal is for indicator lights. The S terminal is not used in Gauges but is still in the harness as is the I wire which is not used.

If it is wired with the idiot light the wire doesn't have to the resistor in parallel with the bulb as the bulb is the resistor, but if the bulb burns out then the resistor in parallel will still send this resistive voltage to the "I" terminal on the Voltage Regulator to excite (tell the alternator to charge). If you run a full 12V to the "I" terminal the regulator will not turn on to charge. (seen others try it and it didn't work until they put a resister in line)
Not 100% sure if you use the wire configuration with the Amp gauge and wire to the "S" terminal if this wire has to be resistive... (I'm thinking maybe not...)
Look at this diagram at wire #98 for idiot light configuration and the resistive wire http://www.fordification.com/images/sch ... master.jpg

[57fordf100]

the "i" on the voltage regulator is run to a condenser then to the ignition coil i seen the diagram everything seems to be the same exept for the resistor that goes from the starter solenoid resister then regulator do you guys think maybe thats y it isent turning on i tested the wires on the regulator the ignition wire has power and the wire to the solenoid has power but the 2 that go to the alternator have no power i ran a wire from the ground on the alternator to the regulator screw were it bolts to the inner fender but i still have no power on those 2 wires

[57fordf100]

ok the "i" on the regulator is running to the ignition the the "a" is running to the solenoid the "s"is running to the top connection on the alternator dosent have any lettering and the "f" is running to the field part on the alternator there is just straight wiring nothing in between the wires

[57fordf100]

ok so i moved the wire that was on the "s" to the sta on the alternator so now i have it "f" to fld "s" to the sta "a" to the solenoid and "i" to ignition coil i have the alternator grounded to the screw that holds the regulator and the battery cable straight to the solenoid is that right?

[Thunderfoot]

You have everything hooked into the right places, the only thing I'm concerned about is the "I" wire. You say you have a condenser in line with it and it is hooked to the ignition coil, this may not work...
Have also seen lots of members get NEW Voltage Regulators that were no good also...

Check the S and F wires with the engine running for voltage, if you have none then it isn't charging. The F wire is what has to have power on it for the Alternator to work, as this wire changes voltage on it to the field, it changes how hard the alternator works (puts out voltage). This F wire gets its voltage from the Voltage regulator so if it doesn't have any voltage on that wire then there is an issue with the Voltage Regulator or the Regulator is not getting the correct signal to turn on (the "I" terminal does this as I posted above).
The Field in the alternator is an electromagnet, the more voltage applied to it the stronger the magnetic field is and the more output the alternator will have. (more voltage/amps)
The "S" wire will only have voltage on it when the alternator is running, this S wire sends voltage back to the Voltage Regulator so it can sense the output of the alternator and regulate the output (feedback type of thing).
The "A" wire is supplying the power for the Voltage Regulator to operate, so that it can send this power to the Field in a variable way to make the alternator work (as explained before)

That is a very basic explanation of how this works...

[57fordf100]

OK i started the truck up this morning and i checked the "s" and "f" on the voltage regulator and there is still no power on them i used a test light and there is no power coming or going to those wires the truck hasent died yet tho wicth is wierd iv been driving it for 2 days now and it seems fine usualy the truck would of died by now no power in the battery what can be wrong

[57fordf100]

OK so i tested the regulator i ran a wire from the A to the f on the regulator and it starts charging the alternator when i run the wire the f on the regulator gets power do u guys its the regulator its brand new imma take it off and have it tested in autozone

[57fordf100]

update i took the regulator off n i took it to autozone and they tested it for me it turn out bad as i thought so they replaced it for me i had them test it and the new tested good so i should have it on the truck tommarow ill test it out i was thinking if the same problem happens to me should i just get a 1 wire alternator that way i can cancel out the regulator

[57fordf100]

ok guys good news i just put the new regulator on and everything is working fine i connected all the wires and started the truck up and there is power on the "f" and "s" on the regulator lets hope everything stays working if not 1 wire alternator here we come