Since my alternator went out, I found a used 2002 model for $60. So I still have my old one that I was going to rebuild. . I was talking with a local company that have been rebuliding alternators for like 30 or 40 years that sell kits. He said having 110 AMP alternator would mot help when you were in a low idle condition. Not sure why. He suggested hooking up another battery if you were going to have winch, KC's, CB etc. Would that act as a stronger battery? Would it not cause voltage issues i.e. 2 12 volt battteries = 24 volts?

Alternators of all sizes cannot provide high current at idle. That's why he made that statement. An alternator provides it's rated output at several thousand RPM. At idle it's barely enough to keep the voltage constant and may sag as you add load.

His recommendation for 2 batteries is valid. You wire them in parallel so the voltage is still 12 volts but your current capacity is the amp hour capabilty of both batteries added together. And the higher output alternator will charge them faster during normal driving.

I would add that you should install a automatic low-voltage cut-off on the second battery and connect all the accessories, winch, aux lights, and etc., to the second battery. This will protect you from a dead primary battery.

Where would it be a good place to install another battery? I thought of a smaller battery. About the size of a motorcycle or a tractor battery with at least 300 cramking amps. I thought that most of the time we only need a backup in case the regular battery cunks out when winching(playing the stereo for a long time). This would allow for the vehicle to be started and the battery charged again. I see very limited space inside the engine compartment. I agree we need the switch to go back and forth with the two batteries. Right now I have a jump start battery pack I carry in back of the truck.

Thanks for the input.

Mar,

I put mine in the back. I ran the wire underneath the truck and up through the back. Walmart carries a black plastic battery case that can be secured. I do not know where else to put it.

An added benefit is that I have a portable winch that you can attach to a traler hitch receiver. That way I can use it in the back to winch backwards.

I also have a battery pack jump starter as well. Overkill, Yes. Let me tell you why. My wife and I were wheelin and were back in the woods about 6 miles on top of a mountian when the alternator went out. We had to hike out. I had my brother bring me a battery. He has a 2 wheel drive. Could not get anybody with a 4 wheel drive to help and it was getting late in the day. I did not want to leave my truck in the woods over night. So we hiked back up the mountain carrying a battery. It about killed me. Got back up, installed the new battery (which is why i have two now,) gulped some cold water way too fast and threw up. I can tell you from experience that if the alternator goes out the battery pack will start the car but it will die. If the battery just goes dead because of a loose connection you will be fine and it will recharge. I usually carry extra coolant, belts, hoses, air compressor, tools and such in the woods just in case. I am gald to have 2 batteries now and soon will have a backup alternator.

As we all know it is not a good idea to go wheelin alone and I usually don't but the wifey talked me into it.

When running two batteries I like using a Batery Isolator. Your alternator will keep both bateries charged but you use the 2nd for your winch and other assessories. Also if your main batery goes dead you can jump yourself <img src="/forums/images/graemlins/lol.gif" alt="" /> <img src="/forums/images/graemlins/lol.gif" alt="" />. If you had your old alternator rebuilt to 110 Amps it would keep both bateries charged (above idle) better. A good place to mount the 2nd battery would be to make a air snorkel and use the spot that the air filters is now.
Dennis

Just one word of caution on batery isolators. Check your charging voltage first, as most isolators will drop the voltage out to the batteries by nearly 1 volt. If your sport is like mine and charges at around 14.5 volts this will be fine, but if you currently charging at under 14 volts you will likely have a problem after the isolator. I personaly prefer to use high current relays. A relay when the connections are properly done will not result in any voltage loss, also remember to install a fuse near both of the batteries, especially if you are running wire thru the body. I am not trying to discount the isolator, I just wanted to show an alternative, especially if you have a lower charging voltage.

I've been installing the isolators in all our Search and
Rescue trucks but they all have 140 amp altinators. I would like to see a diagram for the relays you talked about. The isolators take a fair amount of space.
Dennis

If you plan to use a smaller battery like you said you were thinking about then maybe you could fab up your own tray and put it all the way to the left side of the engine compartment up by the firewall. It seems that there would be enough room there for a battery. Or even a tools box or something.

I'll try to get something together with a diagram, the relay has a major size advantage. I'm used to caling it a relay as that is what we typically referred to it as while I was installing, but it is really a 200 amp solenoid like you'd find in an electric golf cart, electric fork lift, or man lift. If you'd like to take a look at a picture check out mcmaster-carr at www.mcmaster.com and look at page 826