I have a 1968 F-100 2WD. I purchased it in '96. Shortly after, the 302 that the other owner put in blew up. I stored the truck until Dec. 02. I put a reman. 302 back in. From what I can tell, it has a Dura Spark II electronic ignition. The original owner said the old 302 and elect. ign. is out of a '84 Mustang. This is my first Ford and I have no experience working on Fords. Here's the problem. The battery won't charge. The battery is brand new as well as the voltage regulator. The alternator tested as good. I think that I have the wiring from the volt. reg. to the alternator wrong. The harness to the alt. was re-wired at one time with all the same colored wires. I noticed there are 4 terminals on the volt. reg. with letters above each. Can anyone help?

 

The F on the regulator goes to the Fld on the alt. The A on the reg goes to the battery connection on the solinoid as does the bat term on the alt.

The S on the reg goes to the run of the ign switch. This tells the reg to provide field current to the alt. Be sure the regulator is grounded.

 

Hi and welcome to FTE!

If you have idiot lights, the wiring is a little different. The 'S' terminal goes to the stator on the alt. and the 'I' terminal goes to the alt. idiot light.

Barry

 

Thanks for the tips, it seems I have bigger problems. As I said before, the wiring harness was re-wired before I got ahold of the truck. It's wired with the same colored wire. I tried starting from scratch. Somehow I shorted out my elct. fuel pump, volt. reg., ign. control mod. and ign. coil. After replaceing everything, I still don't have a charge. I did have the alt. re-tested after my explosion, it still tested good.

I am going to attempt to use a GM alternator with the single battery lead. I had two different mechanics suggest that as a solution. Has anyone tried this? If so, how did it work?

Again, thanks for the info, I'm just electronically incompetant.

1968 F-100 Stepside

 

I changed the alternator out for the GM alternator with internal regulator. From what I can tell, it is charging. I drove the truck around with the lights on plus whatever load the electronic ignition pulls and the elect. fuel pump. Restarting was perfect. My aftermarket ammeter is not working though. I wired it for the GM set-up, gauge positive to the + battery post and the gauge negative to the battery post on the alternator, but no dice. Does anyone know a simple way to wire the aftermarket gauge? Thanks again for everyone's help.


1968 F-100 2wd step-side

 

Just install a voltage regulator. Easier and gives you better information. The voltage should be around 14v when you are driving.
jro

 

jor, I think you mean voltage METER, not regulator.

 

I'm hooking up my one wire alternator, can I use the Green wire with the red stripe that goes into the S terminal of my old voltage regulator to provide the ignition hot source to trigger the alternator? My truck came with the ammeter and not the light.

 

Hi, I'm not Mike but I think that would be fine.

Barry

 

Thank You. It sure is nice to get that mess of wires out of there. I just hope everything works when I'm done.

 

I found out the hard way(as usual) that the GM alternator I installed is not charging. I noticed the reply to the original message referencing a wire to trigger the alternator. My truck does have the gauge, but it hasn't worked since I have had the truck. Is there an easy way to wire the gauge? And how do I wire the trigger to the GM alternator? The alternator I bought is for a '74 Chevelle. It has the double prong male connection on the alt and the stud on the back. I have a lead wire running to the battery from the rear stud. I am an electrical dummy!!

Note: I had to re-register under my current user name. I could not access any replies under THELAW74 anymore. I sent an e-mail, and someone did reply. I was told that I didn't complete my registration. The funny thing is I posted 3 or so new threads and replied to several threads. I'm just glad that the people replying to these messages have more courtesy than whoever sent me the degrading e-mail.

Sorry for the ranting!!!!

 

I hope this helps! WIRING DIAGRAM GM Alternator:
Install a red 10 gauge wire with a crimp on ring connector from the battery post terminal on the alternator to the positive post on the battery. I used a new red GM Positive battery cable with an extra attached 10 gage wire. A 10 gage wire from the battery post terminal on the alternator to the positive battery cable side of the starter relay will also work.
The Delco GM alternator connector is keyed to fit and will only plug into the alternator one way (the right way). It has two 18 gage leads, a white one solder less crimp connector installed and a red lead about three inches long with a ring connector. The red wire with ring connector connects to the battery post on the alternator, (same post as the 10 gage wire running to the positive battery post). The other wire (mine is white), connects to the ALT light. This must be ignition hot or the alternator will not charde at idle. From the white lead on the alternator plug in connector, run a 18 gage wire under the battery box, up and across the radiator core support and crimp connect it to the 18 gage green with brown stripe alternator charging lamp indicator wire from the bulkhead connector. This circuit operates the alternator charging lamp indicator.

 

Thanks, I'll give it a try next week on my days off. I'll let you know how it works out.

Bryan

 

William, I hooked up my alternator the way you said in your post to me earlier on my '68 but now I have no power to my ignition switch. I'm thinking that I missed something somewhere. There is a 4prong connector that connected to the wires leading to the voltage regulator, they are a 10gauge Black w/yellow stripe, Yellow, Yellow w/green stripe, and a Green w/red stripe. I know that the yellow is for the horn and I routed the Green w/ red stripe for the ignition hot to the altenator. The other wires are not hooked up. So what goes where.

 

William,
My truck has the battery gauge. Do you know if the wire for the gauge is the same color as the light set up?