ok so i just bought my truck last friday. figured it would be a great idea to get the charging system and battery check at the local autozone. he tells me the diodes are bad and that i need a new voltage regulator. so i cnaged it. then i went back to make sure my problem was solved and he said you need a new alternator. so i changed it. so now the truck went from charging fine. to dead and wont charge. i have been troubleshooting this all night and nothing is helping. i have replaced the fusible link and ton of old connections. i am reading 12 volts with the truck at idle across the battery. i am also reading 12 volts from the negative terminal on the battery to the positive terminal on the alternator. when i disconnect the connector to the voltage regulator the voltage on the alternator goes up to 14.

i have tried three different voltage regulators and have had the new alternator tested and it passed. any ideas would be great. i am totally lost and frustrated with this. thanks

 

Don't trust anything the parts guy says. I used to be one, and those handheld testers they use arnt even 50% accurate. I hooked it up to a brand new truck one time just for ****s and it said everything was bad.

Put the old stuff back on and get your money back.

 

I wish it was that easy. All of the old stuff is gone

 

Well then I'll suggest the next cheapest way. Run down to your favorite junkyard and grab an alternator off a early 90's ford v6. Grab the wiring too. This is the "3G upgrade" that everybody does. Very simple to wire, very reliable, good power. And it can be done for less than $30.

Search 3G alternator and you will find lots of info.

 

i was looking at that a bit earlier. i was just concerned about connecting the other wires coming from the currently installed voltage regulator. will it effect the electronic ignition?

 

No. And no.

The 3G alt only uses 2 wires. Charge cable and exciter wire. None of the old wiring is used. If you have an electric choke it is a bit more complicated, but still very easy. The old voltage regulator and rats nest of wiring is all GONE, just gone! No more! Bye bye! And it is replaced with 2 or 3 new wires.

 

Do yourself a favor and do the 3G as stated above. Its very easy.

 

Is there an alternator that will bolt up with out modification the the bracket. Looks like I need the 7" I guess. Which one did you guys use?

 

My truck has a 240 but, this is how I did my 3G swap on my '69 F-100.

https://www.ford-trucks.com/forums/1...l#post14784365

I used the larger cased (148 mm) 130 amp 3G alternator. The smaller cased (135 mm) 95 amp 3G may fit without bracket mods --not sure since I didn't use that version.

 

Either one will fit as long as you get the right one. There are 3 different mount styles. The short 7" one is a direct bolt in.

 

Do you know which vehicle has that 7" alternator. That is what I will go look for

 

be sure to grab a length of the harness from the donor long enough to reach.

 

Best bet is a 90-95 Taurus with the 3.0.

 

Look for the cleanest one you can find. I pulled the regulator and inspected the bushes
stator rings for wear. You need a paper clip to hole the brushes down to reinstall them back into the alternator. I finally found a good newly new or rebuilt.
I took to a near by starter/alternator rebuilder shop and had it tested for my own piece of mine. 14.2 volts and is was a 130 amps.

I drilled and tapped the adjustment arm bolt. I did not need any spacer shims on the pulley as it was perfect alignment with the water pump 2-vbelt pulley.
I did
All in all spend about $65 bucks doing the 3g upgrade.
I use some Shrink tubing, Liquid tape, New 175 plastic fuse holder an so on.
Also New Gates drive belt.
It sure cleans up your engine bay removing all from wires.
Orich