I believe that the component you are looking at is a voltage regulator.

YOU NEED THAT if you don't want to blow up your battery.

Just removing components because you don't know what they are or what their purpose is would be viewed as bad practice.

that's how a buddy of mine nearly burnt down his truck. Just started removing stuff one of which was a black box with a few wires going to it. Don't remember what it was but when he turned the truck on, he heated a couple new splices and other components and then woosh!!!! FIRE!!!!

A couple pounds weight saved = few hundred $$$$ lost on replacing stuff ruined by fire. Luckily he had a fire extinguisher handy.

 

I realize that, but the factory voltage regulator is still hooked up, and if you saw the hack job of wiring that they did on this truck, you would understand why I ask as well as why I have to install a whole Painless wiring system.  Why would the truck need two voltage regulators?  I'm not removing wires just to remove them, but there is no need for extra things either...

Jeremy

 

Intially, I thought it was a dual battery isolater, but I don't recall seeing any connections like that before.
Definitely not a regulator, it would need addtional wires going to it if it were.

 

Not the voltage regulator.'
So, where does the wire hooked to the body go?  Anywhere?  You said it looks like it might have been the old alternator wire.

That thing almost looks like an old isolator of some kind.  That way you could feed 2 batteries from 1 alternator and keep them isolated from each other.

 

It looks like the dual battery isolator that was on my old (73) boat.

 

It's awfully small to be a battery isolator.  Maybe some sort of RFI filter?

 

Maybe an old ammeter shunt. With that big of a heatsink it had something to do with power. But I think shunts had 4 wires.

 

Not the voltage regulator.'
So, where does the wire hooked to the body go? Anywhere? You said it looks like it might have been the old alternator wire.

The wire hooked to the body of the 'thing' is a 10 gauge black wire that comes out of the wiring harness up by the alternator (which, according to my FSM the only 10 gauge black wire up in that area would have went to the main lug on the alternator).

Since you guys have brought it up, there are two battery trays in that truck though, one where it normally goes, and another one on top of the driver's side inner fender (about a foot back from the first one), but I assumed that one was added because the extra wires the last bonehead ran were too short, so they just moved the battery up there . If the truck did come with two batteries, wouldn't there be one on each side of the engine compartment?

Jeremy

 

The truck didnt come with dual batteries someone added them. That being said they could put the second one wherever they wanted.

 

I'm wanting to say the guy I bought it from said it was originally a railroad truck, and when it came it didn't have a front bumper on it....could they have possibly added a second battery to run a winch or something?  I am guessing since I am only running one battery, I could remove it if it was, in fact, a battery isolator.

Jeremy

 

Yes you can remove it, might want to save some of it in case you decide to run duals later.

 

I'd test it.  See what has power where.  It's hard to say what it is but it still looks very small for a battery isolator.

 

I'd test it. See what has power where. It's hard to say what it is but it still looks very small for a battery isolator.

They make smaller.

It looks like the kind used on a lot of tractor trailer- trailers that have a heating system, its not a true isolator, (they have three wires, one input, and two outputs), this is more like a one way switch for the electrical system being used as an isolator, but does a poor job of letting both batteries get charged.

I could remove it if it was, in fact, a battery isolator.

Jeremy

Yes, I would remove it, it will only put an unnecessary drag on the electrical system. Just make sure there are not any unconnected wires from the second battery left connected.

 

Ok, great thanks!  I am completely re-doing the entire wiring harness in the truck, so I would prefer to make everything as right as I can in the meantime.  Thanks guys.

Jeremy

 

Howdy,

Make sure you still have at one continuous wire from alt charge lug to battery, or things will get quiet and dim pretty quick!

Cheers


Chris

 

I still don;t think it's an isolator, but without a detail of the wiring it's hard to say.  It looks to me like some sort of filter or maybe even a voltage reducer.  I'd test it and see what it reads.

 

I still don;t think it's an isolator,

Just do a Google image search or battery isolators. here is one that works the same way.

 

it is an old style isolator.if you test it with an ohmmeter,and if it still works,it will allow current to flow in only one direction.
i think i have seen that style in older conversion vans.
i'd pull it out.
if you ever decide to run dual batteries,get an isolator that is rated much higher than your alt output.
i have seen many of these things burn up,one was on fire as it came into the lot.got it snuffed before anything serious happened.that was the end of dual batteries in the local government vehicles.

continous duty solenoid style isolator is a safer way,but it does have its downfalls.

 

Just do a Google image search or battery isolators. here is one that works the same way.

All the ones I have seen are like this:

or the solenoid style.

 

All the ones I have seen are like this:

or the solenoid style.

No doubt, those are the most common. The other style is used mostly with trailers (RV & commercial), where the other battery is not hooked up all the time, and charging the second battery is not as important as the isolation of the two.

Like ORD says, the best thing to do is get rid of it.

 

This reminds me, where can I get a new battery tray or replacement for my 79 RC.