Anyone evr run dual alternators?

[KYJ10]

I have 3 or 4 old alt laying around here, with a ton of brackets. On my 360, the alt is located toward the bottom and there is plenty of room up top,where an air conditioner would be. Since im running 3 sets of 100watt axillary lights and a winch, why not run 2 alternators? I dont have the dash gage hooked up and am basically running the alt with just one wire. So I would think 2 would do fine? Any thoughts? Dennis

[mdill]

If you run two alts, you will want to still run one regulator. If you run two regulators
they tend to fight each other, as the reguators use a pulse with modulated type
field control, two reguators don't like to play nice together. The other option is
to make a dual setup with a separate system to run you accessories, with it's
own battery and a isolaton relay between the main and the secondary setup.

Mike D.

[Damage, Inc.]

Do you have two batteries?

[KYJ10]

No I have 1 battery and both alt have internal regulators. Sound like too much trouble anyway. Maybe I'll just stick to the single and if I have any problems, i'll add the 140 amp kit to one off them. Dennis

[joe]

Do you "need" 140A alt? I run a 90A on my CJ and it keeps up with a winch and dual batts just fine. I eventually will run an OB welder and I think the alt that come with them squirt 170A's or so but my past experience with 120A alts and larger(some smaller too) is that they won't charge at idle. Sometimes you can get away with installing a smaller alt pulley...sometimes not. BIG alts come with their own piles of grief(not to mention cost). If you don't really need them...avoid mega amp alts.

[Chero77]

Well you could just wire the lights, fans, etc to a seperate electrical system supplied by the second alternator. I don't see why you would need a second battery since you are not going to be using any of that gear except when the engine is running.

[Narnian]

I don't think you are going to get the benefits you are looking for. Everything you strap to that crankshaft robs you of HP. I picked up a 135Amp alternator from some dude on Ebay for $45 set up as bolt in for the AMC 360. He sells them all the time for CJ-7's. If you want to do this for the fun of beating the technical challenge go for it, but if you are really concerned about the lights and winch I think you are robbing Peter to pay Paul and creating new sources of problems for yourself.

The only time I really needed more juice than the stock blender put out was when I wanted to tow a trailer with 12 lights, run my stereo at full blast (250 Watts), run my fog lights, regular lights, defroster and CB during a rainstorm with the windshield wipers going. I fouund out my battery was dead after I fueled up at a gas station. After an hour wait for a jump I turned off the stereo and didn't have any trouble at my destination. Removing any one of those items stayed inside the ability of the stock 65 Amp alternator.

Ever since that incident in the rainstorm, I DO carry one of those $29 jumpstart things, and I keep it charged with a solar panel on my dashboard. I installed the 135 AMP alt so I can use the stereo next time out. In your case, if it ain't broke don't fix it. But if you are thinking you really have trouble, I'd rather buy a bigger alternator than try to rig two to work together.

[Andrew]

I agree with what everyone here is saying too. You can run 2 alts and 2 seperate systems but in reality you don't need it. Dual Batt's will give you much more bang for the buck.

BUT if you are concerned about power loss and effciencey. You can wire your headlights, 100watt lights and other high amp stuff with relays. This eliminates a lot of heat (energy) lost in the wires.