National Luna Dual Battery Install

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Joined
Nov 14, 2004
Threads
157
Messages
1,068
Location
Kansas City, Missouri
I figured I would start a write up on my dual battery install project that is currently in progress. After researching the different options there are for dual battery set ups, I choose to go with the National Luna Kit. There was a great article in Overland Journal well over a year ago on dual battery set ups and it really helped me understand my options. I ordered the kit from Paul at EQUIPT Expedition Outfitters www.equipt1.com . Paul was kind enough to answer any questions I had and delivery of the kit was very prompt. I choose the NL kit over other options for many reasons but a few of them are as follows:
(1)It is a complete kit! Although I did go out a buy a few extra things to complete the install how I wanted, the kit comes with everything you need without having to purchase anything additional.
(2)I’m able to monitor the primary and secondary batteries with the in cab monitoring system (very cool)
(3)I’m able to combine both primary and secondary batteries together to jump start the primary battery if ever needed with a push of a button.


NOTE: I am an electrically challenged and have been taking and listening to advice as I have been doing this install.... disclaimer now set.. ;p
 
Once I had made the decision to go with the NL set up I had to choose what batteries to go with. NOTE: I don’t want to go into the pro’s / con’s of battery options and nor do I want this thread to become that discussion. I choose to go with a Yellow Top Optima Battery for my Secondary battery that will run all of my accessories. Actually my wife purchased this battery for me as a Christmas gift! J I wasn’t going to replace my primary OEM battery, but during the install I had noticed that the positive terminal post was a bit loose and decided to replace it with at 34R Red Top Optima Battery. I should have that tomorrow!

The first step in pulling all the pieces together was to build a tray for my secondary battery. First let me say that I took the baseline design of the Slee battery tray and Spressomons ideas for a fuse block/breaker holder and the additions of lower support legs to fab up the tray. So they get all the credit for how it is designed, I just pulled it all together with some scrap steel in my garage, so thanks guys!
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I live close to a Bass Pro Shops so for convenience sake I purchased all of my accessory fuse blocks and circuit breakers (CB) from them. You can find the fuse block here. And the circuit breakers here. I will have two fuse blocks, one for accessories that sit under the hood and another one that will be in cab for all of my accessories/outlets in the cab of the truck. More to come on that stuff as I start installing them. Each fuse block will be protected by its own 40 amp CB’s and if I ever out grow them, I will simply replace them with larger breakers. Better to have the CB be the weakest link than anything else in my opinion.
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You will see that I decided to use different battery post terminals. The kit came with some really nice post terminals, but I liked the Military spec terminals a bit better for their overall strength and low profile. The ones with the kit would be just fine, but like I said I wanted to do a few things different. I purchased these from my local NAPA auto parts store. Napa part numbers are as follows: #728222 for the negative post and #728223 for the positive post.
Next step was to find a place to mount the intelligent solenoid. I decided to mirror how Paul mounted his. I mounted it on the passenger side between the air box and the new battery tray. Two things needed to be moved in order to give you a flat place to mount the isolator. I moved the small little horn over to the right using an unused factory thread in the fender (simple). I then had to move the Diagnostics plug over to the left. You could just zip tied it out of the way, but my goal was to make the install as factory as possible. The factory little bracket is shaped like a “U”. I cut the bracket vertically in half leaving me with only one side of the “U” with the clip that attaches to the plug. I then welded a small 1/2” x 3” inch (only guessing) long strip of metal to the bottom of the clip. This made an extension log enough to reach a bolt in the fender to hold it in place as far left as the wire harness would allow. In this picture you will see the new placement of the horn and the diagnostic plug giving me enough room for the solenoid.
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After the solenoid was mounted I started cutting, crimping, heat shrinking and running my battery cables. The kit comes with plenty of wire and cable lugs for the install. I had to purchase some additional cable lugs due to using different terminals at the battery than what came with the kit. I was able to borrow a battery lug crimper (the kind you hit with a BFH) from a friend. I know the manual hand crimpers work great, but I didn’t have access to one and I didn’t want to drop big $$$$ on one for a single job. It seamed to work really well, only time will tell. I used heavy wall polyolefin, adhesive lined heat shrink wrap from NAPA. You can buy it in Red #NW 727622 and black #NW 727659, they come in 10” sections. I purchased 2 of each.

I ran all of my wires that go from my primary battery to the secondary battery & solenoid across the firewall. After I had run all of the wiring I decided to cover all of the wire in black wire loom to protect the wire. Some of these pictures are before I added the looming. You can purchase that stuff from Home Depot or even by the foot from…. You guessed it… NAPA…

The kit comes with inline fuses. One 50 amp fuse for the line going from the solenoid to the secondary battery (seen in above picture mounted to the passenger fender well) and one 100 amp fuse to be installed as close to the primary batteries positive terminal as possible. I couldn’t find a good place to mount the large inline fuse, so I built a small bracket to hold it. I can now easily access the fuse if needed.
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The only real tricky part to the install of the kit is the factory negative ground that connects to the negative post on the primary battery must be cut and a new battery lug be crimped on the end. This is due to the factory ground wire is connected to the clamp that wraps around the batter post. To use the battery post terminals that I purchase as well as the ones that came with the kit you have to do this. It was not that hard, I just don’t like cutting what came from the factory. It now is more than likely better that it was before as I added a larger ground wire to replace the small wire that attaches to the body/fender on the drivers side. See pic. The two wires on the left of the terminal are the factory ground wires. The wires on right are the ground wires to the secondary battery and the ground wire to my winch. It is recommended by National Luna to hook up your winch to your primary battery as the alternator supplies a large portion of current to the winch in doing so.
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[FONT=&quot]To hook up the large factory fusible link as seen on your positive battery terminal using the military style post terminals I had to make a small bracket. If you use the ones that come with the kit this is not necessary. This picture shows what the bracket looks like. The very small cable I made is redundant and more than likely not needed, but I wanted to make sure to have adequate electrical flow from the battery to the factory fusable link. I will post up a picture of what it looks like installed once I get my red top in place. [/FONT]
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more to come as I continue working on this project. You can make this install as simple or complex as you like. I tend to go toward the complex in everything I do! ha.. I hope this thread will be helpful to some of you.
 
Looks great so far, when are the finished pics coming! Optima yellows, I've been running them for years as main starting and auxiliary and have had no dramas. I found they really spin the starter motor and fire the engine up quickly (turbo diesel), will be interesting if you note any difference when you put your red in.
 
Looks great so far, when are the finished pics coming! Optima yellows, I've been running them for years as main starting and auxiliary and have had no dramas. I found they really spin the starter motor and fire the engine up quickly (turbo diesel), will be interesting if you note any difference when you put your red in.

I hope to get this wrapped up before Cruise Moab. Step 1 in this project is to get the main system installed. I still need to run and install the in cab battery monitor. I then need to hook up all my accessories, run wire and install rear fuse block, 12v power outlets, etc.. so its a much bigger project to get it all completed and buttoned up. But it sure is fun!
 
You posted a heap more pics while I was typing and got them in before I sent my post!
You may want to get some of these terminal post covers, they cover my military style battery terminals very well.
That's an Optima Group31 in there, I have one both sides, they're big suckers but they fit and they spin the diesel really easily.
Get rid of the small cable that is now replaced by the buss bar.
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Zane: Nice write up! FYI: West Marine also has battery terminal covers in several different sizes.
 
Isn't your fusible link no longer fusible? Is it insulated from the bracket? I can't tell from the photo...

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This wire is NOT a fusible link. it is just a wire. I know its redundant as the twisted bracket will pass the electrical flow to the factory fusible link (the one that is big and black that attaches to you positive terminal). I just wanted to make sure I had proper current to the primary factory system.

see picture installed and connected to the factory fusible link.
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Trumped me again Zane! Nice bracketry and terminations. I like the way you moved the fuseable link away from the battery. It is a tight fit on the Optimas anyway.
 
Thanks Travis! I completed the cables for the circuit breaker and fuse block. I still need to get a nut and bolt to attach the wire to the fuse block, but you guys can get a good idea of the set up from this picture.
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