Was out climbing huge sand hills the other day, with a water pump that was seeping. I should have kept a closer eye on the temperature gauge, but I was too busy having fun bouncing around and climbing huge inclines.

I saw the gauge up in the red and immeadiately popped the hood to find my overflow bottle boiling and in "blow off" mode.. I was like wowsers!!!

I kept the hood up and started feeding my 5 gal water can into the rad the temp quickly came down. I filled the bottle back up and never heard boo from it again. However... This got me thinking about a new project idea

Unrelated ...

I was bouncing around so hard, lol, I can't believe this... The passenger side engine mount broke free from the cradle!! I mean the engine slipped up out of the v block. Totally nuts right?

I will post a pic up in this thread when I get a chance to repair it.

I also need 5 new doors and a set of rockers, I have literally been pounding the piss out of my KJ

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

I know I have been all over the place with ideas and what not.

But materializing in the very very near future will be a dual battery mod and possibly dual alternator, I am picking the brain of certain electricians about the possibility of splicing a second "alternator" harness onto the factory one and running tandem alternators and batteries. Same voltage, double the available amperage... In theory. I dunno for sure tho, I am not a electrical guy. I know the KJ monitors voltage, not amperage, so it may not even know the second alternator is even there.... If the second alternator will even do anything?? I dunno.

Oh and I want a WAY bigger radiator...

This girl can't keep up with my lead foot. Tons of power when cool, and dead as a... I dunno when it's hot.

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

And why the pic below is my motor mount brackets now..................

Dual batteries doesnt necessarily require two alternators.
A single alternator can just as easily charge two batteries as it does one. It just takes it a little longer to do so.

The real question is, how much load are you putting on that one alternator?

If you have a 90 amp alternator and your super duper amplified stereo system pulls 100 amps, then yes, you might need a dual alternator setup. Or you can just replace your alternator with one that puts out more amps.

It really all depends on what stuff you are trying to power and for how long.
Some folks use an isolator with their dual battery systems. The isolator allows you to power whatever accessories you want, while the engine is not running, off a single battery.
Then, when that one battery dies, you still have a fresh reserve battery for starting the engine.
Both batteries are charged by a single alternator.

_________________
U.S. Army Retired

Sexy lookin mounts tjkj!


I want to do dual electric fans, and winching seems to just kill the power, when the fans are running, it takes forever...

I get the whole theory of dual alternator and isolator, I just wanna have tandem systems like they did in the military.

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

I dont know how many amps your stock alternator puts out, but going to a higher amperage alternator would be a lot easier than fabricating a bracket and finding a longer belt.

Electric fans generally pull 8-15 amps. About 15 amps at startup but that drops to 8-9 once running at full speed. And the fans dont need to run all the time. Only when the A/C is on or when the engine gets too hot.
Personally, I think a single 16 inch 3500-4000 cfm fan would be enough to keep the engine cool.

Winches can pull a lot of amps too, but they are never constantly running. This is where a second, high capacity, deep cycle battery would come in handy.
Used with a isolator, it could provide plenty of reserve capacity to support winching.

Have you considered adding a high idle switch?
I have no idea how to install one on a KJ but lots of heavy duty trucks have them for supporting high drain electrical accessories and/or hydraulics.
All it does is kick up the idle speed to where the alternator is putting out max power.

Dual alternator setups are more for engines/vehicles that support high drain electronics that are constantly running.
Such as a large truck with a cabin in the back that has its own air conditioning, refrigerator, IT equipment, etc, etc.

_________________
U.S. Army Retired

I am inclined to agree with you.

I think the alternator I am running at the moment is a 160 amp?? I could be wrong. RockAuto had two options I picked the higher amp one.

If I ran a second alternator, I could put a relay on the field exciter wire and use it only when all the extra bells and whistles and dings are required and leave the stock system alone :s

I really really really need an excuse to make this happen.

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

Amp ratings are a myth on alternators.That 160 amp Renny alternator actually only puts out 112 amps max and the rpm's seen during highway driving,you'd have to be redlined to get close to 160 amps.The stock 136amp alternator puts out like 98 amps at the same rpm's.

If the engine would have to be redlined, do you think it would work having a smaller pulley made up? Like they do with super chargers? You know, to make the alternator spin faster than normal?

Would the belt just slip not having enough contact? Would at that point it be better to move to a mechanical style belt tensioner?

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

I think a smaller diameter pulley would help.
You could probably take your alternator to a shop that specializes in alternators and have them fit a pulley for your needs.

If the belt slips or just doesnt seem to get tight enough, you might have to use a belt that is a few mm shorter.

_________________
U.S. Army Retired

I agree.

I don't really like the whole idea behind the spring loaded tensioner (mines new), having like a 1/4" throw when the engine speed suddenly increases. I know it's menial to worry about such little things but I do.

_________________
2004 KJ 3.7 Limited:
IRO WJ Upper Arm -- WJ Rear LCA's -- Rear Driveshaft Spacer -- JBA Upper A Arms -- 4 inch Lift -- 265/75/16 4" B/S -- WasherBottle Relocate -- Custom High Mount Intake -- Carpet Delete -- Homebrew Winch Bumper -- Warn VR8000 -- Homemade Plow -- Pinch Weld POUNDED -- POR 15 inner fenders --

" I know it's menial to worry about such little things but I do."

Anal might be a better choice of words.

Bob