Right, but what I suggested earlier is that he get the 2G internal regulated harness and do away with the external regulator all together as oppossed to buying the new external regulator kit. The 2G harness will pretty much plug and play into the exisitng electrical system with the very minor mods previously described.

 

Oh, I see, I am sorry, I misunderstood.

 

Nah....I probably wasn't clear enough. At any rate, I think it would be more cost effective for him.

 

I completely agree - either that, or take the 3G harness and solder it into the green and red wire that is already existing.

 

Here is another write up that makes it sound pretty easy to do.

 

Where did you get that one? Its pretty good.

 

I wish I had something like that when I did the install.

 

Ok, I am seriously looking at upgrading to the 3G alternator in the future but the more I dig into this, I’m not so sure this thread can be considered a one size fits all solution for our trucks. Keep in mind I have two big issues preventing me from really figuring this thing out: first off, it won’t stop snowing on weekends around here! and two, I haven’t found a schematic that represents my truck.

These are my concerns so far:
If I read this thread correctly, we are to abandon the original harness to the Alternator

So moving forward, the 3G charge current will flow thru a new charge cable and mega fuse of sufficient gauge/amperage. When I look at my 86 F250/460cid, I have only one connection (in addition to battery cable) at the Batt + connection of the starter relay. This connection is a 16ga fusible link. Is that my existing charge current circuit? I don’t think so. It’s my understanding that when correctly sized (4 number sizes smaller than the wire in the circuit they protect), a 12 gauge circuit gets a 16 gauge fusible link, 6 inches long. So based on this I I’m thinking it may be the Alternator Field current supply circuit. There is a large yellow cable (10ga?) running from the alternator to the cab via the alternator harness. If I read the thread correctly, this cable will be abandoned. Again just guessing here but I would expect anything connected to the yellow cable to be “dead” at this point? I would almost expect that cable to be re-terminated at the starter relay Batt + connection?

The other question I have that isn’t as pressing; it has to do with the charge gauge circuit. From what I understand, the charge gauge is really a voltmeter across a shunt in the existing charge cable. If the original charge cable is taped and stored out of the way, how is this circuit to work?

Sorry if I’m missing something really simple here and like I said, I have not had a chance to do my homework on these questions yet, just throwing it out to the group.

 

The yellow wire is essentially live at both ends. It's live at the alternator, and live at the top because it draws power through the fusible link which in turn draws power from the battery cable to the solenoid. You're only disconnecting one end. The ammeter will still work through that wire. One thing to remember about the factory harness is they are barely sufficient for the 60 amp units. When I took mine apart I found it was only connected by about three remaining strands and definitely would have caught on fire if I hadn't dome away with it.

 

I'm not sure I just save all upgrades but I think someone posted it in the diesel forum, as quite a few has done it. I haven't done it yet but Just picked up 2 3g alternaters.

 

Look at the alternator harness from Ford Fuel Injection.
There is no reason to run the yellow wire from the solenoid.





You can see that the yellow wire just connects back to the output stud feeding sensing current to the regulator.
The green/red wire provides the current to excite the alternator.

 

I had tried to unplug the factory harness from the truck and mine would not start, so I had to plug it back in for the truck to work.

 

Jim...There are probably differences in the stock alternator harnesses with the newer trucks. I don't see how that harness would translate to an 80-86 setup.

 

An '86 has a 1G alternator?
Separate wires and a fender mounted regulator?

I thought I was replying to bghnkinf250 & Bernie.



EDIT: This is what I remember being schematics from FFI/RJM injection.

1G wiring:



3G wiring after conversion:


3G_Alternator

 

My 86 has a 2g, the Flaming Ford alternator, it is all based on options which you have, but most have the 2g in 86