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3G alternator new or used?

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Gary Lewis

Re: 3G alternator new or used?

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At least you have a good plan. Good luck!

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

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

In reply to this post by 86-350-460-dually

Adam,

Do you have a 1G alternator (wires and cable bolted to the back, external regulator mounted on inner fender)

Or a 2G alternator (two 3 pin plastic plugs connecting it to the truck)?

If the latter, CLOSELY inspect the lower plug with two black/orange and one white/black wire.

This is the source of many charging problems and more than a few fires.

In fact, if you do have a 2G you should probably change it as a matter of course.
I got fed up with dead batteries and blown alternators and finally 'upgraded'. But like I said $10 & 10 minutes is quick and cheap compared to the alternatives.

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.

86-350-460-dually

Re: 3G alternator new or used?

There has been quite a few modifications done to the truck previously, that I don't know what I have is stock or not. I believe my truck should have had the 2G stock, but I couldn't tell you if that's what I have or not. There is no external fan on the passenger fender.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

Hmmmm

I don't see plugs OR multiple wires on the back.

Or even a proper spacer on the pivot bolt!

The 1G external regulator would look like a tin box about 5" square usually with four wires.

It may be some aftermarket one wire alternator and a bunch of barnyard engineering went into that.

Wish I had a better answer for you.

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.

86-350-460-dually

Re: 3G alternator new or used?

Uh ohh.... That's kind of concerning haha. So just to clarify, it's definitely not a 2G?

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

85lebaront2

Re: 3G alternator new or used?

Administrator

It looks like it might be a Government Motors alternator, they were popular for a 1 wire setup. Ford 1G used a remote regulator, 2G AKA flaming Ford used an integral regulator and two molded plugs, 3G uses a 6mm stud and a 1 and 3 wire pair of plugs. GM built a close to the same size that could be used as a 1 wire alternator.

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

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

In reply to this post by 86-350-460-dually

I'm trying to look at these pics on my phone, but it doesn't look like it has a brush pac and regulator attached to the rear like a 2G.

The kinda rounded corners remind me of a 1G, but then you would have a separate regulator on the inside fender.

This leaves me thinking 'aftermarket one wire Chevy style alternator'
Unfortunately, these perform poorly because they have to be self exciting. ie, there is no key on source of power to wake it up.

Maybe Gary or one of the guys with a decent monitor can better identify it.

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 new or used?

Administrator

In reply to this post by 85lebaront2

Thanks Bill!

Now we need to find the dead diode that's killing the battery, and a solution to get his truck charging.

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.

85lebaront2

Re: 3G alternator new or used?

Administrator

Taurus 3.8L 3G and snag as much of the wiring harness as you can, it runs from the alternator across the top of the radiator then back to the underhood fuse box near the windshield on the driver's side. The plugs for the stator and "tickler" wire run in with the output wire.

He also needs to find a correct length and size bolt for the alternator, mine for the original setup is long gone.

Bill AKA "LOBO" Profile

Gary Lewis

Re: 3G alternator new or used?

Administrator

In reply to this post by ArdWrknTrk

You'se guys are doing great!

If he's running a GM 1-wire wouldn't the easiest fix be a 3G? We shouldn't assume that the shunt/ammeter has been bypassed, but hopefully it has.

Adam - Have you noticed the ammeter move, either positive or negative?

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

Yep
3G.
Get the wiring *and* the fuse/holder assembly off the relay box on the driver's side.

Tap the adjuster ear 3/8"-16 NC.
Hammer the existing adjuster arm a little flatter so it lines up with the 3G.
Splice the lt. green/yellow exciter wire to key on power.
Loop the yellow to the output stud with a ring terminal.
Make the charge cable fit somehow, with copper lugs torched on.

Tell me if I missed something...

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.

Gary Lewis

Re: 3G alternator new or used?

Administrator

I think you have it all, Jim. But, just in case here's the 3G page: http://www.garysgaragemahal.com/3g-conversion.html

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

This post was updated on .

Yes, I looked at your instructions and even mentioned them earlier.

So... Swap the pulley, with shim.

Bill says get the right pivot bolt (and spacer) instead of the janky stud that's there.

I'm thinking may be better/cheaper for Adam to get a 3G retrofit regulator pigtail (eBay, 119851 under/around $10) than buy crimpers, terminal set and that pricey little stator plug.... which also fits a compressor clutch.
-you know the one-

Then he only needs to connect green to key on power.

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 new or used?

Administrator

In reply to this post by Gary Lewis

BTW, not to be pedantic, I noticed your tutorial says 8.125" mounting, but it is 8.25" as shown in Ryan's pic.

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.

86-350-460-dually

Re: 3G alternator new or used?

In reply to this post by Gary Lewis

Holy smokes! Haha. Sounds like I have some work to do? I understand Gary's tutorial fairly well, the two things that I'm not understanding is the janky stud (what do you mean by that?) And can you explain what you mean by the fuse box connector thingy? I'm not quite understanding that.

Also, Gary, you asked about my ammeter? I assume that's the D&G meter in the dash? No, mine does not work one bit. Here's a pic of what I have, it's out of focus and I can get another if you need a clearer picture.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

In your first picture the alternator is pivoting from a *stud*, with a nut and washer at the front.
That needs to be a long bolt. So you can pull it out and swap the alternator.

Also notice the free space behind the alternator pivot boss.
You can clearly see in the rust of the mounting bracket where there used to be a spacer sleeve that kept the alternator from shifting back on the bolt.

When you find a 3.8 liter Taurus you will take all the wiring -back to the power distribution center (box) on the driver's side.
The thick charge cable should connect to a fuse similar to what Gary shows.
This fuse *should be* in a small box (holder) attached to the front of the PDC. I'm not sure if all model years were set up this way, but I have taken the holder with the fuse and the cable leading into the box.
This saves having to buy an aftermarket holder like Gary's picture.

Yes, you have an ammeter.
Follow Steve's advice and eliminate the big coil of wire up inside the dashboard before you start a fire in the cab.

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.

86-350-460-dually

Re: 3G alternator new or used?

ArdWrknTrk wrote

Yes, you have an ammeter.
Follow Steve's advice and eliminate the big coil of wire up inside the dashboard before you start a fire in the cab.

I'm sorry, which one is Steve and I think I missed his suggestion about a coil of wire in the dash...?

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

In reply to this post by Steve83

This....

Steve83 wrote

The shunt doesn't really go to the ammeter - it goes to the battery & all the electrical loads. The ammeter is ACROSS the shunt (it reads the voltage developed by current passing through the shunt's resistance, but displays that as an inferred amperage). So regardless of the alternator type (1G, 2G, 3G, 4G, Leece-Neville...), it's a poor circuit design and should be converted ASAP to a low-resistance wire (shorter & without all the connectors) & a true voltmeter. Most especially if you've swapped to a HO alt.

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.

86-350-460-dually

Re: 3G alternator new or used?

Ah! Sorry, I did read that. Thanks. I'll have to look into that.

Adam

1986 F-350, Dually 4WD, C/C with the 460/7.5L

ArdWrknTrk

Re: 3G alternator new or used?

Administrator

In reply to this post by Steve83

And this.....

Steve83 wrote

I'm saying the alternator doesn't matter, period. I advise everyone to re-wire the charge circuit like a stock 3G's for better performance, more safety, and more functionality - even with a stock 40A alt.

It's not a joke when you have a resistance wire glowing red hot up inside the dash where you can't get at it

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.

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