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Installing a second alternator

762 Views 3 Replies 3 Participants Last post by  Junk Yard Genius
For those of you that are running a second battery for winches etc., and are sort of limited because of your pcm controlling the field circuit, has onybody ever thought of just installing a second altenator? A friend of mine that ownes a Scout did just that. It is a pretty cool setup. He just installed a complete charging system for his auxiliary battery, and completely isolated both the battery and charging system for it. Now he has aver 190 amps total for his electricial system. Can anybody see any drawbacks? It looks kind of wierd with two volt gauges on his dash, but he only has about $50 bucks invested.

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I know the NJ Police cars are starting to use double altinators.

1997 TJ w/ 33's & 1984 CJ7 V8/35's
I've seen cars with competition sound systems that have as many as 10 alternators. And Jeeps with a second alternator converted to a welder.

Wayne in Hawaii
I need to get with that guys' parts supplier!
Second battery, battery tray, battery tray brackets and tie down, alternator, alternator brackets, alternator connectors, alternator wiring and fusible link, and I assume starter cables and starter solenoid so the second complete charging system can be used for something, and all the miscellaneous loose hardware it takes to do an install like that for $50 !!
I NEED to meet that guys' supplier!

Even if your buddy had ALL of the stuff laying around, everyone else here is going to have to pay for it.

I can see the need for a second battery for added reserve while winching or running radios or something while the engine is off and the alternator isn't charging.
A second alternator does you no good at all when the engine is off anyway.

(my opinion, not to be confused with fact)
I don't think a complete separate charging system is needed unless you would be running continues operating loads that far exceed maximum alternator supply.
(back to facts)
An ambulance is a prime example.
So are any vehicles that operate outside of available support, like long range operations vehicles.

Some of the long range vehicles and industrial vehicles also have two starters .


I guess if you are doing a geology survey in a remote mountain range, 500 or 1,000 miles from the nearest garage,
OR, If you were driving an ambulance or fire truck and lives depended on it...
OR, If you were 1,000 miles out to sea,
OR, If you were taking care of daily operations inside the Arctic circle or Antarctica...
A second charging and starting system would be a necessity, not a frivolous extra expense and added extra maintenance so you can point to and tell your buddies,
'Lookie There What I Done!!'.....

Another use of the extra charging system would be someone that had 11 dozen huge off road lights, or those stereo guys.
No matter how many alternators you have running, if the engine is dies or is switched off, that stuff is useless anyway, and you are back to batteries. (for a few minutes anyway...)

We built the mini van that Kenwood used for stereo demonstrations a few years ago...
Half of it's total weight was batteries. It was useless for anything but making noise.
About 5,500 watt continuous drain.(figure that for 12 volt batteries!)
It was a nightmare to keep operational.
We lost real money on that deal.

I'm so glad it self destructed.
The shock waves created by the sound tore the body seams apart (we had nothing to do with the body...). It was always parked within a few spaces from us at the car shows, and it got really old to hear that, 'BUMP- BUMP- BUMP' crap all the time. You couldn't talk to customers, hell, you couldn't even think.
(My personal opinion is that is why the current generation is so far down the tubes, all those sonic blows to the head have turned their brains to mush.../wwwthreads_images/icons/wink.gif)

(my opinion again...)
I don't see why the average guy would need a complete second charging system.
However, I do see a lot of potential for a second battery, and it's pretty easy to install. You don't even need to isolate it if you watch what you are doing, and don't leave the lights or some other current drain on...
(end of opinion)

To each their own. If you want wiring diagrams of dual batteries, or dual charging systems, let me know and I'll whip them up.

Later, Aaron.

If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?
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