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3G Alternator Wiring

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FormerBigDaddy

3G Alternator Wiring

I’m just about ready to go with this and wanted to confirm something that isn’t covered on the conversion page... and that is the plug pictured below, specifically what to do with wires OTHER than the green/red wire.

Large Yellow: This now needs a ring terminal and goes to mega fuse in 3G set up?

Red: Not used? Cap off?

Yellow/green: Also not used? Cap off?

Green/Red: I know this goes to 3g alt “I” (This info is covered everywhere)

1984 F350 460 Auto

Gary Lewis

Re: 3G Alternator Wiring

Administrator

It looks like you've gotten a plug from a different source than I've seen and the wire colors are different. So we have to figure out where each wire goes in the connector to ensure we understand

In my pic below there are three wires in the main connector, and the regulator has the lettering A S I on it. If your regulator has that lettering you can plug the connector in and figure out which wire color matches to what the writeup says:

A: Yellow/white wire that tells the regulator what the alternator's output voltage is. It can go directly to the output stud of the alternator or it can go to the alternator's side of the fuse/fuse link.

S: Black/white stator output and that wire wraps back to the middle terminal on the regulator's plug. But, if you have a 7 volt choke be sure to see the Choke tab, above.

I: Light green/red wire that tells the regulator that the key has been turned to On. This wire will connect to your original light green/red wire, regardless of whether your truck has an ammeter or idiot lights.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

85lebaront2

Re: 3G Alternator Wiring

Administrator

Gary, that's not even the correct plug, that looks more like a piece of 2G or 1G harness. That is one of the 80s weather proof "pull apart" connectors.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

Gary Lewis

Re: 3G Alternator Wiring

Administrator

Good catch, Bill. I didn't look closely enough. That won't even plug into the alternator.

Gary, AKA "Gary fellow": Profile

FormerBigDaddy

Re: 3G Alternator Wiring

In reply to this post by Gary Lewis

Gary I’m good with the wiring of the internal regulator and 3G alternator. I don’t have any questions about the S, I, or A wire.

The picture I posted is the female end that will go back in the truck. Maybe seeing the other end will help.

Again, the question is about the BIG YELLOW WIRE. According to schematic I’ve seen it goes to the mega fuse. Wanted to make sure that’s right.

I believe the red wire and yellow/green are not used in 3G and can be capped off. (They were for ammeter).

Green/Red goes to “I” in back of 3g alternator.

1984 F350 460 Auto

Gary Lewis

Re: 3G Alternator Wiring

Administrator

Ok, I'd assumed that was the connector to the 3G, and obviously it isn't. My bad.

That appears to be Connector C610, as shown below. I've circled the four wires that should be in it. Is that correct?

The expectation was that you'd leave that connector in place. The big yellow wire is a main power feed to the truck and is necessary. The two wires to the ammeter (R/O & Y/LG) can stay if you aren't replacing the ammeter, although it will always show discharge. And the LG/R would be picked up where the old regulator was on the fender and fed to the 3G's regulator.

Have you already cut the wires, like it looks like in the pic?

Gary, AKA "Gary fellow": Profile

FormerBigDaddy

Re: 3G Alternator Wiring

Yeah the wires are cut like in the pic.

The big yellow wire had to be cut since it went to the factory splice. Where does this big yellow wire go now? Mega fuse?

Is it a problem that I cut the Red wire and yellow/green wire?

This is what I was going off of.

1984 F350 460 Auto

Gary Lewis

Re: 3G Alternator Wiring

Administrator

The yellow wire was protected by Fuse Link J in my diagram above. And just taking it to the Megafuse won't really offer the correct protection. Fuse Link J is probably a 14 gauge wire and may be able to pass 70 amps w/o melting. The Megafuse is probably a 150 amp, right?

You can connect the yellow wire to the Megafuse, but if you get a short in the yellow wire it'll melt it quickly w/o blowing the fuse. I wouldn't. I'd connect it back to Fuse Link J.

The red/orange and yellow/green are for the ammeter. Are you going to use it or replace it with a voltmeter?

There were lots of good things about RJM, but that diagram is not one of them.

Gary, AKA "Gary fellow": Profile

FormerBigDaddy

Re: 3G Alternator Wiring

This post was updated on .

Well I’m lost now. I’ve read so many posts, threads, and websites about this 3g conversion and didn’t see that big yellow wire talked about anywhere. Yes the mega fuse I have is 150 amps.

I didn’t have current plans for a voltmeter and I had only read that the ammeter would no longer properly function without converting it to a voltmeter. So I guess the answer is no, I didn’t have plans for a voltmeter or the ammeter.

1984 F350 460 Auto

Gary Lewis

Re: 3G Alternator Wiring

Administrator

Yes, too many cooks in the kitchen....

I'm headed out to church and won't be able to work this until afternoon. But we can get you through it.

Gary, AKA "Gary fellow": Profile

FormerBigDaddy

Re: 3G Alternator Wiring

What does Fuseable Link J look like?

1984 F350 460 Auto

ArdWrknTrk

Re: 3G Alternator Wiring

Administrator

The note in the EVTM says it's either 16Ga (orange) or 14Ga. (Green), depending on the alternator output.

Either way, it is spliced to the black/orange wire leading to the cab.
It has rubber insulation and a black collar with tab or ear at the ring terminal end where it attaches to the hot side of the fender mounted starter relay

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

FormerBigDaddy

Re: 3G Alternator Wiring

The black/orange wire is originally spliced with the bigger yellow wire I’m talking about along with the yellow/green wire.

So you’re suggesting I should reconnect the larger yellow wire with the black/orange wire along with the yellow/green? Obviously I wouldn’t include the end of the black/orange wire that powered the 1g alternator?

1984 F350 460 Auto

ArdWrknTrk

Re: 3G Alternator Wiring

Administrator

You asked what fuselink (J) looks like.....

You only need the three wires in the 3G regulator plug and the charge output cable going to the Megafuse.
(S) bk/w goes to the choke
(B) y/w goes to the output stud
(I) r/lt grn goes to power in crank and run.

On that plug, that you show, the only wire you really want is the r/lt grn (key on power) wire.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

FormerBigDaddy

Re: 3G Alternator Wiring

Ok, so then what happens to the big yellow wire? Doesn’t that power the lights in inside the cab?

And the red wire and yellow green can stay disconnected?

1984 F350 460 Auto

ArdWrknTrk

Re: 3G Alternator Wiring

Administrator

Cab power should come from the chassis side of the Megafuse, or the hot lug of the fender mounted starter relay.

The ammeter can stay disconnected, but the shunt wire needs to be bypassed.

Isn't all this in the 3G tutorial page?

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

FormerBigDaddy

Re: 3G Alternator Wiring

So my original thoughts are correct? Large yellow to battery side of the mega fuse or starter solenoid and the other 2 wires (red and yellow green) are unused and I can cap them off and out of the way?

1984 F350 460 Auto

ArdWrknTrk

Re: 3G Alternator Wiring

Administrator

In reply to this post by ArdWrknTrk

Take connector 610 completely out of the picture.
None of that is needed with the 3G.

You need yellow wire 37 to the fused side of the alternator output, and you need the light green/red wire to the (I) of the alternator regulator plug.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: 3G Alternator Wiring

Administrator

In reply to this post by FormerBigDaddy

You don't need to cap them, nothing is flowing there.
If you choose to modify the ammeter to a voltmeter later you may still want them.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

FormerBigDaddy

Re: 3G Alternator Wiring

Are you saying this plug below doesn’t need to even go back into the truck?

1984 F350 460 Auto

3G Alternator Wiring

3G Alternator Wiring

Re: 3G Alternator Wiring

A: Yellow/white wire that tells the regulator what the alternator's output voltage is. It can go directly to the output stud of the alternator or it can go to the alternator's side of the fuse/fuse link.

S: Black/white stator output and that wire wraps back to the middle terminal on the regulator's plug. But, if you have a 7 volt choke be sure to see the ​Choke tab, above.

​I: Light green/red wire that tells the regulator that the key has been turned to On. This wire will connect to your original light green/red wire, regardless of whether your truck has an ammeter or idiot lights.

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Re: 3G Alternator Wiring

S: Black/white stator output and that wire wraps back to the middle terminal on the regulator's plug. But, if you have a 7 volt choke be sure to see the Choke tab, above.

I: Light green/red wire that tells the regulator that the key has been turned to On. This wire will connect to your original light green/red wire, regardless of whether your truck has an ammeter or idiot lights.