Alternator Not Working Please Help 19 years old Need Help!!

[72Highboy]

Hi everyone. First of let me give a quick update I am 19 and know a lot about mechanic's but not much about wiring. I really need help on this because its what I use to get back and forth to college. I have been carrying around extra batteries and every so often swaping them cuz I have to drive it till the battery dies. I have a 1972 F100 360 5.9L V8 standard transmission. The owner I bought it from couldn't figure it out and sold it cheep. I have replaced the voltage regulator thinking it was the problem but it wasn't I later bought a new alternator and installed it, and still my volts read zero. I was wondering if putting a new voltage regulator will prevent the alternator from working or if it will short out on a bad alternator. I have pulled my hair out trying all night to fix this instead of working on my school work. I really dont have the money to take it to a shop for them to find a simple problem and charge me up the azz. Please anyone else out there with the same size engine and such help me out or if anyone can help me please it would very much help me out. This is my daily drive and what I use to get to college.

[papabug71]

Welcome to Fordofocation !! How are you reading the volts?? Do you have an aftermarket voltmeter installed, or are you going off the factory gauge ??

[Wes]

here is a link to a schematic for the 72 F truck http://www.fordification.com/tech/wirin ... _quick.jpg, You need to make sure you have 12v at the alt, that your reg has a good ground. If your new reg is a solid state (ie electronic) it might be damaged by a bad alt, if it is mechanical prob not. double check all the connections are clean and tight. Check the fusible link connected to the batt side of the starter relay. Hope this help some.

you could upgrade to a G3 alt http://www.fordification.com/forum/view ... =8&t=13062

[fordman]

take it to autozone they will test it for free.

[papabug71]

Has it drained a batt. since you installed the new alternator. or are you just worried about the reading from the stock amp meter. The stock amp meter on these trucks is, to put it niceley, worthless. They dont move like you think they would. I have owned my truck since 1994 & can count on one hand the # of times it has moved....

[72Highboy]

I am reading off the factory guage and with a hand held meter from Lowe's Improvement. I have traced alot of the wires they seem fine, I think the alternator isn't waking up, if you know what I mean. I bought a new voltage regulator and put it on and started my truck. After seeing no volts I replaced the alternator, hopeing I didnt fry the voltage regulator, (is that possible) it might be a solid state one I went into autozone and told them my problem and they sugessted the voltage regulator and I told them my truck specs and stuff and they went to the back and brought me the part. I will check all the connections and such. I will get back with the color of the wires coming from the alternator to the voltage regulator and to the starter relay/junction box tomarrow.

[72Highboy]

Thanks for your guys advice I will get back with the colors of the wires coming from the alternator and voltage regulator, and I will take acouple of pics and maybe a couple of you can help out that way and post it tomarra. Thanks again I got to get started of homework.

[slamons]

I had the samething happen, checked everything two or three times, found the problem in the hard plastic gromet that blots to the back of the alt. Inside this harness the wires were broken apart, cut it open, reattached the wires to the alt with new connectors and all works well with the exception of the gauge. But like everyone says it is nearly worthless anyway...

[70_F100]

take it to autozone they will test it for free.

Try that first.

[m-mman]

Yes the factory amp gauge is not a reliable way to determine if the system is actually servicing the battery.
So how do you tell?
AND do so with a mininum of tools?

1. The battery is constantly going dead and nothing is draining it. (lights left on, etc.)
2. With the engine running, pull a battery cable. If the charging system is working at all the engine will stay running. A weak charging system may not be able to keep up with the lights on and the A/C operating and a big amplifier all working but it should at least keep the ignition working. If it dies when you pull a cable the charging system aint functioning.
3. Check the VOLTAGE at the battery WHEN THE ENGINE IS RUNNING. A 12 volt battery should show 12 volts but a functioning charging system should show 13 to 14 volts if it is charging properly.
4. Having a device to sense the actual amperage that is moving into (or out of) the system is the gold standard but this requires more tools and knowledge.

[cep62]

With the engine running, pull a battery cable. If the charging system is working at all the engine will stay running.

Back in the days with generators this was standard practice.
This is not recommended with alternators ,it can cause damage.

Check the VOLTAGE at the battery WHEN THE ENGINE IS RUNNING. A 12 volt battery should show 12 volts but a functioning charging system should show 13 to 14 volts if it is charging properly

This is the best simple way to tell ,turn on all your accessories and speed the engine up a little, if it can maintain 14 volts you're good to go.

[fordman]

i tthought the damage could only occur with the alternators with electronic diodes in them. but i dont know.

[70_F100]

i tthought the damage could only occur with the alternators with electronic diodes in them. but i dont know.

Fordman, all diodes are electronic...

[fordman]

well what i am tring to say is i do not know if our alternators had the newer diodes in them or not. i was thinking they may have had soemthing else. and didoes were a newer thing in alternators. i do not know.

[72Highboy]

First of sorry I took a while school work. Her are some pictures I took of the way my wiring is set up. Let me Correct something I know for sure my alternator is working its in the wires some where or the voltage regulator is bad. I will try what you did slamons which wire was broke in the hard plastic you cut open. I have done where I have had my truck running and pull one of the cables and it does die. The batteries are all new. I have been looking online and matching wiring diagrams and this seems right, I am also gonna buy a new voltage regulator and see if thats the problem if it doesnt work I am gonna try to wire it myself or decide to take it to a shop. Thanks for all your guys advice and help. Very Much Appreciate it.













This is my baby