MO POWAH!!

[LILCBRA]

So I installed a 3G alternator in my car today. The original plan was to use a 3G alternator that I had when I got some parts for the GT. When I went to re-clock the alternator so the plug was pointing the right way, the damned casing come apart too far and broke one of the two brushes in the housing which necessitated a new one. After having to make a run to O'Reilly's and Autozone for some 4 gage cable, ring connectors, a 175 amp Mega Fuse, and the new alternator, then a second trip out to the Depot for some miscellaneous bolts, it's in the car. And it works. BUT...... the voltage jumps at idle from around 14 to as high as 45 volts. I'm gonna go out on a limb and say that the new alternator has a bad voltage regulator. I followed the instructions from PA Performance, so I don't think I did anything wrong, but it's hard telling.

 

[LILCBRA]

Pulled the alternator back out, swapped the pulleys and took it back. They tested it 3 times and it was good each time, so I come back home and threw it back in. Just as I was finishing it started to rain, but I went ahead and tried it again. This time it stayed down between 13 and 15 volts. All I did was unplug everything and plug it all back in.

Forecast calls for rain until the weekend, so I won't get the chance to really check it out til then.

The swap is pretty straightforward if anyone wants to do it. (@Enzio , @2Blue2 ) I bought the 3G harness adapter and replacement "voltage regulator" from LMR. There's only 1 wire in the original harness you'd have to tap into, otherwise everything else is new. The pulleys swap, the mounting tabs are right, etc. Well, except the locking tab, the small one. It's a through hole, not threaded, so you'd need a longer 3/8 bolt and nut. But going this route should allow you to add any electrical load to the system without having to play Apollo 13 games.

 

[Enzio]

Next thing on my list.

 

[Manoah]

I’m gonna need this in about a year.

 

[2Blue2]

The ladies like a man with a big alternator.

 

[LILCBRA]

Now the forecast calls for rain through the weekend.

No matter though, I went ahead and ordered a new voltage gauge and while I'm at it I'm gonna add an engine vacuum gauge. Probably gonna have to mount them where I used to have the temperature and oil pressure gauges before I mounted them in the pod with the A/F gauge....

 

[429MII]

I have to play dumb and admit I don't know what the heck a 3g alternator is... but it sounds like something good... lol

 

[LILCBRA]

Ford's 3rd generation alternator. The 1st Gen put out 60 amps if you were lucky. The 2nd gen, which is what's in my 87, is apparently problematic. I can say I've had one in the 84 when I swapped the Mark VII 5.0 into it. It froze on me while I was on the highway, so I can attest to that reliability issue. They started putting the 3rd gen in different cars starting in, I think, 95. The SN95 5.0s and V6 cars had them as well as a few others. So if you need to keep the mounting locations like the 1st Gen with opposing mounting holes, these are the ones to grab. The 3rd gen puts out 130 amps minimum, so more than double the 1st gen.

This is one of the articles I referenced when I jumped into it. There's some good info in there.

How-to Install a High-Output Ford 3G Alternator into Older Fords

A Ford 3G integrally regulated alternator is the best choice for replacing old 1G externally regulated alternators on amped-up muscle cars.

www.hotrod.com

 

[Enzio]

Ford's 3rd generation alternator. The 1st Gen put out 60 amps if you were lucky. The 2nd gen, which is what's in my 87, is apparently problematic. I can say I've had one in the 84 when I swapped the Mark VII 5.0 into it. It froze on me while I was on the highway, so I can attest to that reliability issue. They started putting the 3rd gen in different cars starting in, I think, 95. The SN95 5.0s and V6 cars had them as well as a few others. So if you need to keep the mounting locations like the 1st Gen with opposing mounting holes, these are the ones to grab. The 3rd gen puts out 130 amps minimum, so more than double the 1st gen.

This is one of the articles I referenced when I jumped into it. There's some good info in there.

How-to Install a High-Output Ford 3G Alternator into Older Fords

A Ford 3G integrally regulated alternator is the best choice for replacing old 1G externally regulated alternators on amped-up muscle cars.

www.hotrod.com

Thank you for this!

 

[Enzio]

So the 3G doesn't get the little fan thing behind the pulley?

 

[LILCBRA]

No, it's actually installed inside the case, so really all you need to do is add the appropriate pulley and you're golden.

 

[Enzio]

What did you do with the leads to the Ammeter on your dash?

 

[LILCBRA]

All I did was follow the instructions that came with the kit. Obviously, the heavy gauge goes to the battery, then one wire attaches to the positive lead on the alternator, one lead attaches to another point on the alternator, and the last lead attaches to one wire in the original harness. Then you replace the regulator with the new one, which is supposed to do whatever voodoo it does so the ammeter works like it's supposed to. At least that's how I understood it. You'll need this kit:

PA Performance Mustang 1G to 3G Plug Upgrade 462802C1

Upgrade from factory 1G alternator to 3G style and retain your factory wiring and gauges.

lmr.com

Their instructions are provided in a link toward the bottom of the page.

 

[Enzio]

So I'm assuming there is a different shunt in the new "voltage regulator" to allow the ammeter to function without starting a car fire. I'm a little confused on that as the voltage regulator on the 3G alternator is attached on the back. That's where the harness plugs in.
With the new alternator installed with the kit from post #13 your stock ammeter operates in the mid range of the gauge? That would be very cool.

 

[LILCBRA]

Yep, it points north like it always has. I have a voltmeter waiting to be installed now, but while I have been cleaning things up around the carport/garage I've not found my double gauge mount. As I mentioned somewhere, I'm also mounting a vacuum gauge and I don't want to mount them separately. I probably should just throw them in the car anyway and worry about the dual mount when I find it.....

 

[7991LXnSHO]

The second gen alternator did not have enough output to run everything on a fully loaded car, and not enough for a thumping stereo or electric fan. That was the problem,

Ford's 3rd generation alternator. The 1st Gen put out 60 amps if you were lucky. The 2nd gen, which is what's in my 87, is apparently problematic. I can say I've had one in the 84 when I swapped the Mark VII 5.0 into it. It froze on me while I was on the highway, so I can attest to that reliability issue. They started putting the 3rd gen in different cars starting in, I think, 95. The SN95 5.0s and V6 cars had them as well as a few others. So if you need to keep the mounting locations like the 1st Gen with opposing mounting holes, these are the ones to grab. The 3rd gen puts out 130 amps minimum, so more than double the 1st gen.

This is one of the articles I referenced when I jumped into it. There's some good info in there.

How-to Install a High-Output Ford 3G Alternator into Older Fords

A Ford 3G integrally regulated alternator is the best choice for replacing old 1G externally regulated alternators on amped-up muscle cars.

www.hotrod.com

 

[LILCBRA]

I've only really had one that I've driven on a regular basis that I can recall, and that was the aforementioned Lincoln swap. Any others that I've been around didn't lock up like that one and they weren't pushed since those cars were stock (my sister's 85 GT, my brother's 84 GT....). The reliability issue I was referencing was a quote from the article I linked.

"Playing catch-up, Ford didn't come out with its first integrally regulated alternator until 1982, when the model 2G alternator appeared. The 2Gs were offered stock in 65- and 75-amp ratings, but they had reliability issues even in bone-stockers. "

My 87 still has the 2G, but it's hardly been driven since I bought it. By time I get around to doing anything with it I'll probably go ahead and go with the 3G anyway. Just seems like what needs to be done.

 

[7991LXnSHO]

My newest a Mustang came with a 3G swap, and I looked at quite a few to find one already clocked right when it went out. (I could have clocked it, but thought why if there is a direct fit.) The other Fox body cars I have owned wore out the air pumps, but not the stock alternators. Warranty returns at the part store were more common on similar era GM alternators, so I’ll take the article with a grain of salt.
Either way, the 3G is an improvement I hope you find trouble free now!
Edit: when one air pump went out, the front came off the shaft while parked at college. The belt tension rolled it across the parking lot and onto the nearby fairway. I wish I would have been watching when it happened.

 

[Enzio]

PA Performance Mustang 1G to 3G Plug Upgrade 462802C1

Upgrade from factory 1G alternator to 3G style and retain your factory wiring and gauges.

lmr.com

Their instructions are provided in a link toward the bottom of the page.

I read them. Did the one you installed come with an internal wiring diagram? If so could you snap a pic and post it? Not doubting you but I'd like to see how they did what they did with the shunt.

 

[LILCBRA]

I'll look around, but I don't recall an internal diagram.