How To: 130 amp alternator in a 2.9

[94xlt4.0]

This is how I installed a 130 amp alternator into my '90 Bronco 2. therangerstation.com and I are NOT responsible for any damage you do to your vehicle by attempting to recreate this swap.

Things you'll need:
130 amp alternator from a 3.8 liter V6 Mustang, Thunderbird (non supercharged), Windstar, etc.
About 25 inches of 2 or 4 gauge battery cable (2 is better)
140 amp mega fuse
female spade terminal
alternator bracket from 80's Chevy 350

Tools needed:
socket set
wire cutters/ strippers
24mm socket
impact wrench or socket wrench for the 24mm socket


1. ALWAYS remove the negative battery cable when doing electrical work.

2. Remove the air intake hose and air box then the alternator belt

2. Remove the two bolts holding the alternator on as well as the two plugs and remove alternator.

3. Remove the bolt holding the alternator bracket and remove the bracket

new bracket on the left, old bracket on the right

4. Take the white wire from the rectangle plug and cut it near the plug. Solder the female spade terminal to this wire.

This picture was found on Google by Twister (thanks for the help). I did not move the yellow wire from the regulator plug shown in this pic because it runs to the power distribution box already anyway.

5. Take the 24mm socket and use an impact wrench to remove the nut holding the pulleys to the alternators.

junkyard 130a alternator on the left, old 60 amp alternator on the right

pulley swapped

6. Install the new alternator bracket and the new alternator. Your stock belt should work (mine did)

new alternator installed

7. Take the battery cable and install the mega fuse. (I bolted one end to the post on the starter solenoid and the other end to the battery cable.)

8. Plug in the regulator plug(D shaped plug), stator wire (spade terminal) and attach the battery cable to the post on the back of the alternator.

9. Re-install the air intake hose and the negative battery cable.

Here is the final product:

There is about 1/4 inch between the hose and bracket

There is about 1/2 inch between the alternator and the valve cover

Overall the whole swap took me about and hour start to finish. Before the swap the dash lights would dim if i turned on anything electrical. Now, I can have 2 sets of auxiliary lights, my headlights, my subwoofer and the heater or a/c full blast and there is no dimming at all. I am very happy with the swap and HIGHLY recommend it to anyone with charging issues or any electrical add ons.
Special thanks to Twister for the help with the wiring department.

 

[4.0B2]

Good Stuff. I like it.

 

[Mark_88]

Good writeup...if it was a 2.3 I'd really appreciate it more...

 

[DisturbedMXer8]

Awesome, man. Thanks for posting this. Definitely on my soon-to-do list.

 

[Schnot]

Thanks! I was looking for a write up on this!

What year mustangs had that alternator ?


Sent from my iPhone.

 

[94xlt4.0]

No prob guys i was doing the swap anyway so i figured i would write this up since nobody else had one yet. My alternator was from a 95 windstar but i believe any 3.8 liter that is not supercharged SHOULD be the same. you can also use the alternator from the f series and broncos with the 4.9 straight 6 as that is what i was originally looking for

 

[maria1019]

Good Stuff. I like it.

 

[kimcrwbr1]

About the only thing to add would be run a ground wire 8-10 guage from the alternator chassis to battery neg especially if you live in a colder region. I have been thinking on adding a internally regulated alternator to my 83 this looks to be the best way.

 

[94xlt4.0]

it was a simple swap for me. i recommend it to anyone who has the 2.9 with a bad alternator as well as any 2.9 with any extra electricl draws. i also thought about adding the ground wire and still might but i haven't had any issues with not having it.

 

[sid]

Great write up ---- a 86 5.0 130amp alternator fits my 2.3 with a slight mode to my alt bracketm, also had to clock the hookups

 

[Twister]

Woot, thanks for the Special Thanks . This swap is so easy everyone should do it. I was about to make a write then i saw yours, didn't think we needed two of them. I would like to add, do a thorough job looking over the alt when you get it from the junkyard. I got mine tested and it tested ok but the regulator was busted which caused my battery to die as well as blow my mega fuse.

 

[94xlt4.0]

Woot, thanks for the Special Thanks . This swap is so easy everyone should do it. I was about to make a write then i saw yours, didn't think we needed two of them. I would like to add, do a thorough job looking over the alt when you get it from the junkyard. I got mine tested and it tested ok but the regulator was busted which caused my battery to die as well as blow my mega fuse.

no problem, thanks again for the help, good call on the inspecting too.

 

[Mudhound]

Okay. I am a little confused here. Where does the white wire "plug in"at? I feel kinda dumb asking this, as I can figure out how to thin out the underhood wiring from a 93 Explorer to just what I need to run the motor, but, not how to connect one single little wire on an alternator.

 

[AllanD]

Damn, I wish I'd swapped a 95A 3g Alternator onto a buddy's 1989 Bronco2 AFTER I finally got dragged screaming and kicking into Digital photography.


I do wonder why you didn't simply adapt an alternator "pigtail" off of a 1993-94 Explorer

This pigtail includes a double fuseable link rated at 160amps and though I did my
4.0 conversion the way I did to eliminate as many fuseable links as possible, I've
never actually seen one of the "double links" on the 1993-94 Explorers "blown"

I've seen the "Singles" that were retrofitted onto 1991-92's blow when someone
ran a 130Amp alternator on a "single" link.

Last note, a 100amp mega fuse on a 130amp alternator?...

Just think on that a bit...

 

[94xlt4.0]

Okay. I am a little confused here. Where does the white wire "plug in"at? I feel kinda dumb asking this, as I can figure out how to thin out the underhood wiring from a 93 Explorer to just what I need to run the motor, but, not how to connect one single little wire on an alternator.

the white wire plugs in on the back of the alternator on a small plug with a single spade style terminal

Damn, I wish I'd swapped a 95A 3g Alternator onto a buddy's 1989 Bronco2 AFTER I finally got dragged screaming and kicking into Digital photography.


I do wonder why you didn't simply adapt an alternator "pigtail" off of a 1993-94 Explorer

This pigtail includes a double fuseable link rated at 160amps and though I did my
4.0 conversion the way I did to eliminate as many fuseable links as possible, I've
never actually seen one of the "double links" on the 1993-94 Explorers "blown"

I've seen the "Singles" that were retrofitted onto 1991-92's blow when someone
ran a 130Amp alternator on a "single" link.

Last note, a 100amp mega fuse on a 130amp alternator?...

Just think on that a bit...

there is no fusible link in the system. i ran a straight cable from the charging post on the alternator to the hot side of the starter solenoid. it was easier than trying to track down the fusible set up from the explorer. also, i only used the diagram as a reference because it is using a 95 amp alternator. i actually used a 140 amp mega fuse as stated in the parts list. i chose 140 amps for two reason, i was always taught to go 10-15% higher on the fuse than the circuit will draw at max capacity. the 10% was 13amps over the 130 which gave me 143. i would rather have had a 150 amp fuse but it was twice as much and a special order at any local place. i havent had any issues with a 140 but if i do i will change to a 150 at that point.