[kevinmrowland]

The Overly Complicated Approach to Dual Batteries


Desmogged 85FJ60
Alternator bracket from a 62
OEM;
Alternator
Fusible Link
Wiring Harness (part of it anyway)
Ignition Relay
Water Pump Belt

Non OEM;
106mm Pulley
8mm spacer for tensioner bolt

On an FJ62 the alternator goes where the FJ60 smog pump sits. The 62 bracket bolts directly to the 60 block and body mount.
The bracket needs to be cut a little to give the alternator enough room to swing.

[kevinmrowland]

The belt from a 62 will not work because the 62 block is shorter, so the water pump is closer to the crank, sooooo the belt is to short.
The 60 smog pump pulley is much larger than the alternator pulley and they are not interchangeable.
A 44” belt will fit just fine with the stock alt pulley, but it is hard to find and it is NOT OEM TOYOTA. Which when it comes to belts is very important.
So I sourced a larger pulley from an alternator shop and modified it to work.
106mm O.D. 17mm Bore. 16mm belt groove.

[kevinmrowland]

This is the wiring diagram. The only difference from what I put in the truck is that the white wire goes to the fuse before the I.G. relay. The charge and discharge of the two systems are completely separated.

[kevinmrowland]

There is a spare spot that fits another ignition relay almost perfectly, the little guide rail just needs to be thinned down with a dremel tool.

[GLTHFJ60]

That is pretty amazing. How did you route the cables from the second alternator? Did they go directly to the second battery?

[kevinmrowland]

Wiring the relay, before and after.

[kevinmrowland]

You can see the new mini harness wired into some of the spare fuse spots on the bottom of the fuse box. There are 5 empty spots that I can fill with fuses and run power to various accessories.

[kevinmrowland]

The parts are all interchangeable and OEM so there are fewer spares to carry. (ultimate redundancy)
I ran a battery cable over to the main battery to facilitate self jumping (eventually I will put a battery switch on there) You can see the overflow bottle has been moved to the fender where there is already a nut of the same size. And I used two sexy new battery trays from stainlesstrays.com.
All finished.

[kevinmrowland]

Originally Posted by GLTHFJ60

That is pretty amazing. How did you route the cables from the second alternator? Did they go directly to the second battery?

Did you reply before or after I posted the wiring diagram?
The wires travel exactly the same as they do in the OEM setup, just in a different one.

[GLTHFJ60]

Sorry. That was a premature reply to your post.

Definately an original solution to the age old problem of not having enough power.

[94landcruiser]

Very cool. Thanks for sharing!

[sandcruiser]

looks good.

I'd reroute the air intake.... higher is better than lower, but otherwise, a very elegant solution all the way around. Thinking about doing something more or less similar in my HJ60.. but no smot pump location to take advantage of :(

[euclid]

Wow.

[RredFJ40]

Cool. A couple of considerations to think about (and maybe you addressed them or they are inconsequential): #1 Does the larger diameter pully spin the alt fast enough to generate good voltage (mostly at idle)? #2 Is having the alt underneath the PS pump a good idea considering that it will eventually leak?

Otherwise, very nice. Wish I was adept in the way of the electron. I have trouble with basic wiring.

[kevinmrowland]

Way to drag up an old thread.
In this case I happen to have a certain affinity for the topic at hand, so I don't mind..........

Sandcruiser, I'll trade you my dual alternator for your HJ.
The Air intake comes out at the same point as stock, right behind the headlight. Snorkel someday.

RredFJ40, I was concerned about the pulley size, and at a low idle the volts are a tad lower than at speed, but the motor only needs to be at about 800rpm before that alt takes full effect, really not that high.

PS pump leaking on an alt is better than leaking on a smog pump, if it does leak on it and happens to effect it, no big deal, I have 2 under the hood now.
I suppose it is no different than having the smog pump in the same location.



P.S. After field testing this for the past few months,........... I really like it.
All things electrical just seem to have more juice/faster response and having the high watt headlights run of the other battery is great.
Not even mentioning the whole fridge thing, which just kicks serious a$$

[CaliCruiser]

Very nice workmanship on the project and very well thought, nice job

Dylan

[Elbert]

that looks like a good setup. Sure make sense if you have a electric winch and or high powered lights / radio. i've been thinking about the same thing.

You running two 55amp alternators?

[Tinker]

Cool!
Is that an E-Jag or a Lotus in the background of the bandsaw pic?

[FJ40Jim]

Late E-type.

Do I win a prize?!

And Kevin, that is an excellent way to fill the smog pump location.

[Mark W]

I routinely run second alternators in that location. One is even just there as a replacement for the smog pump so that the belts all work right, not even wired in yet...

But I've never done it quite that cleanly...


Mark...