Do I Really Need Dual Batts? What say you? (3 Viewers)

Stumpalama

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So, I've been thinking lately about swapping my carb for a SNIPER EFI setup with a surge tank pump in my 1981 FJ40, and as I survey my engine bay, I don't see a lot of white space to accommodate the surge tank.
I installed dual batteries back in the day, when we used to drive the 40 twenty miles out to the trailhead and wheel in remote locations where you brought what you needed to ensure you could get out of the woods and drive your rig home.
Now that my rig is an East Coast trailer queen that wheels 90% of the time in ORV parks, I'm debating the need for dual batteries, or at least 2 full size batteries. I could use the space, for sure.

I will also be replacing my single cylinder VIAIR compressor with a recently acquired ARB dual pump, so that has to fit too.

What are your thoughts?

Ignore the :hillbilly:bungy over the batteries, that was for a road test after finishing the dual battery tray. It has been replaced with a legit steel bar.
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If you are not wheeling or doing trips that benefit from dual batteries then yeah I'd eliminate one. Any long winch fests you have to deal with when the engine if off?

I'd just get one of those small starter/jumper packs that can jump your rig if the single battery goes low. That will get you back some reassurance you get by having two batteries.
 

Stumpalama

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If you are not wheeling or doing trips that benefit from dual batteries then yeah I'd eliminate one. Any long winch fests you have to deal with when the engine if off?

I'd just get one of those small starter/jumper packs that can jump your rig if the single battery goes low. That will get you back some reassurance you get by having two batteries.
I have a hi output alt and don't anticipate long winching sessions without the engine running. I also have a NOCO jumper that is the bomb.
 

GLTHFJ60

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If you are not wheeling or doing trips that benefit from dual batteries then yeah I'd eliminate one. Any long winch fests you have to deal with when the engine if off?

I'd just get one of those small starter/jumper packs that can jump your rig if the single battery goes low. That will get you back some reassurance you get by having two batteries.

Exactly the same advice I'd give. If it were a diesel, that might be different, but with a 2f yeah, no need IMO.
 

Stumpalama

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Exactly the same advice I'd give. If it were a diesel, that might be different, but with a 2f yeah, no need IMO.
I knew I could count on you, Johnny.
How about one of these Dyna-Batts for dedicated starting and one of my yellow tops for all other loads?

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GLTHFJ60

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That battery has a tiny capacity, only 16AH. It would work for starting, but if you had to winch with the motor off like @boots4 was suggesting may happen, then you wouldn't be able to winch very far.

If you're still running a yellow-top with that, then how much space are you really saving? Run a single, decent size, AGM and jumper cables :hillbilly:
 

Stumpalama

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That battery has a tiny capacity, only 16AH. It would work for starting, but if you had to winch with the motor off like @boots4 was suggesting may happen, then you wouldn't be able to winch very far.

If you're still running a yellow-top with that, then how much space are you really saving? Run a single, decent size, AGM and jumper cables :hillbilly:
Solid reasoning.
 

GLTHFJ60

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FWIW, from 2007 until 2014 I had a single battery (even with my 4bt) with no issues. I added the second battery only to have more reserve capacity for running a fridge. If you don't have that kind of accessory load, I don't think it's necessary at all to have dual batteries.
 

Stumpalama

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Single battery and put a real fuel pump in not that surge tank stuff. Too many possible leaks and takes up space.
Yeah, I hear ya, but it may be an interim solution because I don't want an external pump. I have a spare 1981 FJ40 fuel tank that I could modify for an in-tank pump, but that will take some planning.
 

Stumpalama

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FWIW, from 2007 until 2014 I had a single battery (even with my 4bt) with no issues. I added the second battery only to have more reserve capacity for running a fridge. If you don't have that kind of accessory load, I don't think it's necessary at all to have dual batteries.
Yeah, no plan to run a fridge in the 40 in the near future. The dual Batts came in handy a few times but unless I move somewhere where I am regularly wheeling in remote places I think its time to downsize.
 
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I too, think a good single fuel pump in the tank is the best solution, but may be painful/expensive to do. It is the best approach and worth doing though.
 

Stumpalama

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I have a tank from an '81 FJ40 that I can modify. It has been empty for years and is ripe for modifying. I just need to take another look at it and double check the clearance from the body floor. Fi-tech Hyperfuel and Holly are the 2 pumps I was considering.
 
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Regarding the AGM, I read somewhere on MUD that it can be drawn down so low that the NOCO won't work. I went conventional after reading that.
 

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