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How to install a one wire 3G Alternator

Heus33

Bronco Guru
Joined
Jun 1, 2005
Messages
7,407
I've waded through a lot of posts and had a lot of questions on how to wire my alternator. Its WAY easier that I thought it would be - here's my experience on my 76 351W.

Purchased a 105A 1 wire alternator from quality power (http://www.qualitypowerauto.com/catalog.php?item=17). Make sure you get the correct pulley (I needed a serpentine pulley).

You'll also need some 4ga wire (I used long battery cable wire from the local parts store), a 175a mega fuse and a fuse holder.

Disconnect your batteyr and remove the old alternator. You can also remove the voltage regulator and associated wiring. See first pic for the "stuff" that I removed.

Next, wire up your fuse to the positive side of your starter solenoid, then run that wire to the red post on the alternator.

Don't forget to cut the old harness (pic 2) and run the black/yellow wire to the positive side of the starter solenoid so you retain power to your fuse panel. Pics three and four shows how I wired my setup. The other wires from the harness are not used and can be taped off. ** You will lose the use of your ammeter with this setup **

Thats it. Hook up your belts and you're good to go. Way easier that I thought it would be. Should take about 30-45 min if everything goes as planned. Might be a good idea to replace your old worn out battery cables as well.
 

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Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,316
Don't forget to cut the old harness (pic 2) and run the black/yellow wire to the positive side of the starter solenoid so you retain power to your fuse panel.

You should really have a fusible link between this wire and the solenoid. If the old black-red wire is still in place on the solenoid it may have the fusible link still. If that's the case the black-yellow wire can be eliminated or you can connect it to the black-red wire on the firewall side of the existing fusible link.
 
OP
OP
Heus33

Heus33

Bronco Guru
Joined
Jun 1, 2005
Messages
7,407
You should really have a fusible link between this wire and the solenoid. If the old black-red wire is still in place on the solenoid it may have the fusible link still. If that's the case the black-yellow wire can be eliminated or you can connect it to the black-red wire on the firewall side of the existing fusible link.

Interesting - why? There was never a fusible link there before. If one is needed, any recommended fuse size?
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,316
There should have been a 16 gauge one at the end of the black-red wire which in reality is the other end of the black-yellow wire. Think of it as a master fuse for everything inside the cab. The fusebox takes care of the most of the circuit protection but there is no protection for most of the underdash wiring without the fusible link. It's good insurance.
 

JakeAlex

Sr. Member
Joined
Sep 7, 2009
Messages
654
Loc.
New Albany, MS
Don't beat me up too bad but what are the main reasons for upgrading to a 3g? I've see a few threads in my short time at cb but never really paid much attention.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,316
Don't beat me up too bad but what are the main reasons for upgrading to a 3g? I've see a few threads in my short time at cb but never really paid much attention.

More current to run accessories, gets rid of external regulator and excess wiring, keeps voltage high at idle speeds to prevent dimming of lights.
 

stock1970

Bronco Guru
Joined
Apr 2, 2008
Messages
1,793
Loc.
Olathe, Kansas
devils advocate, on the other hand if the voltage regulator goes bad you half to replace the alternator with the 3g .. but old school you only replace the reg.
 

jmhend

Bronco Guru
Joined
Dec 25, 2007
Messages
2,733
going to the pull a part this weekend anyone know of a donor vehicle?
 

RRRAAAYYY2

Bronco Guru
Joined
Nov 10, 2004
Messages
1,684
Loc.
Brantford, Ontario
devils advocate, on the other hand if the voltage regulator goes bad you half to replace the alternator with the 3g .. but old school you only replace the reg.

Four Torx bolts on the back of the laternator and the brushes and regulator come off the 3G. Rebuilt 1000's of them, almost always reused the regulators as they are near bullet proof.
 
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