Dual Alternators

[TegGs]

Has anyone ran twin alternators? Just looking for pics of brackets. I'm running a secondary deep cycle for the winch and lights and I would like it to have its own power source.

[4DI2D]

Your best bet for winch power might be twin golf cart batteries (6 volt in series) and a battery isolator. IDK but an alternator could best be mounted in place of an AC compressor.
6Ga welding wire comes to mind.

[JBfab]

Someone on here had a second mounted up for trail welding. They put it inplace of the smog pump and i belive it was a gm style one wire. Id hit up fireguy (ryan) for a high amp 3g. I think he has them up to 120 amps.

[Steve83]

Originally Posted by TegGs

...I would like it to have its own power source.

That's not how it works. Just like the batteries, the alternators should be in parallel. Attempting to isolate them only creates a HIGH risk of fire & electrical damage to every system & component on the truck. Your best move is to simply upgrade to a junkyard 130A factory alternator. If you find it's not enough, THEN go looking for a higher-output single aftermarket replacement.

Ford never offered dual alts on a Bronco, but this album shows a factory GM arrangement, including the wiring diagram:



This shows how Ford wired dual batteries:



This is how mine are wired:



This is where the 2nd battery is installed:

[351w500]

Fireguy goes up to 160 amps.

[Saltlife]

Originally Posted by 351w500

Fireguy goes up to 160 amps.

I have Fireguys 3g 160 amp and it seems to run everything just fine. I have winched, HIDs, and small system in the bronco.

[351w500]

i got me one too, giggity.

[BigBlue&Goldie]

Definitely stick with one alternator; we only run one on our race car and keep a spare mounted under the hood for backup. Like the others have said, a single high output unit will fill your needs with less drag on the motor and less potential for problems.

[mkinsman]

wouldnt it just make sense to go to a higher amp one then run 2 lower ones? that just seems to make sense

[TegGs]

Thanks, I got thinking about it and for the cost of doing it I'll just do a 3g swap. A guy locally has 3 alternators in his jimmy and 4 Gell batteries. Friggin cool setup. I'm working on a way to mount a secondary battery and isolator setup instead.

[BigBlue&Goldie]

3 alternators........does he weld while he winches with his high beams on?

[Madcat455]

Originally Posted by BigBlue&Goldie

3 alternators........does he weld while he winches with his high beams on?

Stereo systems.... When I used to compete in IASCA, it wasn't out of place to see 2 or 3 alternators to run all those high power amplifiers(Along with 10-20 batteries.. lol).

Heck, I could drain my battery in less than 10min @137db. Headlights would literally SHUT OFF as the bass hit. Was considering a 2nd alternator before it was all ripped off.

[helirich]

Interesting idea. My understanding of a alternator is that it senses the bat volts and puts a charge on if needed. So if you wire two in parallel and there was enough draw to exceed one alternator, I'm sure it would work fine. The question I have would be, would they share the work?

For example, if one alternator was running and not to max output, the volts would be at aprox. 13.5. So if you connected a second alt, it would sense that voltage and determine that no charge is required.

Of course if both were hooked up from the start, maybe they would share. But maybe one would start charging a little before the other and the only time the second would come into play was when the first was exceeded. (and the voltage dropped)

I guess you could run two "one wire" altenators to two selinoids. Then you could pick which alternator you want to run that day (or both if needed)

My opinion would be that the only reason you would want two alts is for redundancy. If you want more power, get a bigger alternator.

[bulrid8]

Most Ford ambulance packages run dual alts.

One charges dual batts in truck and one charges dual batts in the box.

For just dual batts I would run a higher output single 3g. Keep it simple.

[DNBELOWBRONCO]

I have Ryan's 3G 160 set-up and it works fine with HID's, Stereo, winch, and rock lights. I run a single Walmart Everstart Maxx 850cca battery and at some point will buy another and will run them together with an isolator just for peace of mind off-road. I have used Motorcraft batteries, Optima yellow & red tops, and Ever-Ready's but for the money the Maxx with it's 7 yr 3 yr free replacement warranty has never let me down and can be returned to any Walmart in the U.S. and you know there's tons of them in every town. The isolator will let you run them both or use one for wheelin' and winchin' and rockin' out in the camp site and still have a charged one to get you home while it charges up the first one. I think the thing I like best about it is you can use one battery to "jump start" the second in an emergency! Really dual 850's and a 3G 160 should be all you need anywhere with way less clutter! -Kevin-

Check out Steve's post above, http://www.supermotors.net/registry/media/905321, and his link to his Supermotor's site with the Ford isolator wiring schematic....

[JohnMcD348]

Just as everyone else has pretty much said, stay single with a Hi output 3G unless you are looking at doing something like an onboard stick welder setup or something like that. Unless you're running a setup that's requiring massive amounts of power like an emergency vehicle, I doubt going to a 160a 3G wouldn't solve any problems

[helirich]

The reason for doing this would be for redundancy. (if your alt quit, your other takes over) lets face it, you could have two batts and a 160 amp alt. but if that alt quits at night, you could run the battery's down before getting home. (depending how far you were.)

[BigBlue&Goldie]

Originally Posted by helirich

The reason for doing this would be for redundancy. (if your alt quit, your other takes over) lets face it, you could have two batts and a 160 amp alt. but if that alt quits at night, you could run the battery's down before getting home. (depending how far you were.)

This is why we carry an extra in our race car. Swapping an alternator is cake, so its not worth it in our eyes to run duals, and we are all about dual everything.......fuel pumps, ignitions, CV boots, belts, etc.

[Kalashnikov]

The new trucks, the diesels at least, have a dual alternator option.

The 80-96 diesel trucks with dual batteries have the battery terminal on the passenger side for the positive with a "T" with battery cable coming out both sides. One side goes to the starter and the other right to the second battery's positive terminal.

I plan to add second 3g and 2500 watt power inverter (continuous wattage).

[DNBELOWBRONCO]

Originally Posted by BigBlue&Goldie

This is why we carry an extra in our race car. Swapping an alternator is cake, so its not worth it in our eyes to run duals, and we are all about dual everything.......fuel pumps, ignitions, CV boots, belts, etc.

That's actually how I will be doing it after I buy another battery and the isolator switch. For me it would be easier and I am a huge advocate of having spare parts handy whenever I go camping, wheeling, or on extended road trips like SoCal etc. I used to keep a spare 65 amp alt after replacing mine just so I would have a trail spare but sold it after upgrading to the 160. Good you mentioned it so I can add it to my future, (my wife's gonna divorce me) , parts list.
-Kevin-