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Dual Batteries

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G
I just bought a dual battery tray for my CJ7. I would like to see some recommendations on what type of batteries to use...Optima Red or Yellow or one of each. Accessories include winch, off road lights, CB, and stereo. How do you recommend hooking them up? I've read to hook them up in parallel instead of using an isolator.

Thanks,


Mike
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Use an automatic battery manager. Two batteries unless they are exactly alike (which no two would be) will drain each other if left unued for a time. I have seen it happen in as little as one week. One battery has a higher internal resistance and it will pull current through it from the other battery until it has a higher resistance and so on until heat generated from resistance has caused both batteries to die. If you do not plan to be in an extreme off-raod situation - on your side or top - the optima's are a waste of money. There are cheaper batteries than can hold up to vibration just as well as long as you don't need the upside ability of an Optima.

The automatic manager will take charge from the alternator and send current to both batteries as necessary and deliver current from each battery or together as needed for your accessories. Do you winch that much to need two batteries? What kind of alternator do you use?

Hank

5
/wwwthreads_images/icons/smile.gif Do a search and find Joe's photo of his very sanitary twin optima setup using the isolating solenoid and the oil pressure switch.....beefy and simple. Look under dual batteries....we beat this subject to death. Of course I'm here to tell you that the only way to go is with a continuous-hold solenoid which is pulled in by an oil pressure switch/wwwthreads_images/icons/crazy.gif

CJDave
Quadra-Trac modified by the crack moonguy/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/tongue.gif transfer case team.
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In a nut shell how does that work Dave? Ill let my Navy electrical training (22 years ago,)take over from there, (they still use vacume tubes for everything, Right?).
Jeff
89 Wrangler

5
/wwwthreads_images/icons/smile.gif You can go to the auto parts and buy a regular solenoid that is made to stay closed for extended periods....they call them CONTINUOUS HOLD solenoids....and then THAT feeds the second battery (+). So, when the solenoid is open, the (+) of the second battery is not connected to the #1 battery(+). Then you use a Hobbs oil pressure switch that closes on rising oil pressure, and you use THAT to feed the new solenoid. The Hobbs gets current from the ignition "RUN" side of the key. TeamRush posted an excellent diagram and so did someone else...I can't remember who...but cjJoe has some real good photos of his bulletproof setup. Just do a search...it's all there./wwwthreads_images/icons/crazy.gif

CJDave
Quadra-Trac modified by the crack moonguy/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/tongue.gif transfer case team.
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Thanks,
Nice simple set up.
Jeff
89 Wrangler

7
/wwwthreads_images/icons/smile.gif My moonguys/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gifstand in awe of the utter simplicity of that diagram/wwwthreads_images/icons/crazy.gif

CJDave
Quadra-Trac modified by the crack moonguy/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/tongue.gif transfer case team.
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The diagram is simple enough to understand but I have one question...If I have my oil presure line hooked up already with a
mechanical type guage...how do I hook up another oil presure that is needed in the setup? Maybe I am missing something!

Alec

10
/wwwthreads_images/icons/tongue.gif Alec....this is your lucky day..../wwwthreads_images/icons/smile.gif My best moonguy-in-chief-of-lubrication/wwwthreads_images/icons/wink.gif just got back from Massilon Ohio where he was consulting on a big standby generator job. His thoughts are that you are already set up/wwwthreads_images/icons/smile.gif and just by popping in a "line" tee, you can insert the Hobbs oil pressure switch in the line which feeds the gauge/wwwthreads_images/icons/cool.gif Usually, it is easiest to do it where it originates at the engine block, because those plastic lines which feed the gauge are not really able to be "teed". Additionally, the line will not mechanically support the heavy Hobbs oil pressure switch. So, just install the line tee.....(that's a tee with a male-female-female tread arrangement)....then screw the oil pressure gauge feeder line in one hole and the Hobbs in the other/wwwthreads_images/icons/smile.gif BTW...tees are always called out as : RUN-RUN-SIDE OUTLET....male-female-female/wwwthreads_images/icons/crazy.gif

CJDave
Quadra-Trac modified by the crack moonguy/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/tongue.gif transfer case team.
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Glad to hear that your best MoonGuy made it back ok! Thanks for the info., it definitly makes sense now!

Alec

G
I think the best isolator/combiner on the market is the Hellroaring unit http://www.hellroaring.com

Their site contains a wealth of information and different setup idea. Their support is also incredible.

hope this helps
A.B.
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