Need help installing volt gauge...

[latrucker]

I am in the process of replacing my old ammeter with a volt gauge to go along with the 4g upgrade I am working on. First off, is it possible to replace the ammeter without removing the cluster from the dash? It looks possible but would like some experienced opinions before I waste my time trying it. Second, the two thick black wires that go to the ammeter. I know one powers the the cab functions (assuming its the black with yellow stripe) so it needs to be connected to a constant 12v source. What is the best thing to do with these two wires once they are removed from the ammeter? Should they be connected to anything in the cab?

 

[B RON CO]

Hi, the wire which goes through the loop on the amp gauge is very important and should not be messed with. You can just cut the loop on the amp gauge to remove the wire, and push it out of the way. I think you would have to remove the speedo cable and the 4 dash screws and twist the speedo down to work on it. Follow the instructions to hook up your new volt gauge. I would think most key on wires could feed the volt gauge. If your wires bolt to posts on the amp gauge, splice the together and tape the up as best as you can. Good luck

 

[latrucker]

Hi, the wire which goes through the loop on the amp gauge is very important and should not be messed with. You can just cut the loop on the amp gauge to remove the wire, and push it out of the way. I think you would have to remove the speedo cable and the 4 dash screws and twist the speedo down to work on it. Follow the instructions to hook up your new volt gauge. I would think most key on wires could feed the volt gauge. If your wires bolt to posts on the amp gauge, splice the together and tape the up as best as you can. Good luck

I don't see any post or connection on the back of the ammeter just a plastic loop that the wires pass through. I am looking at it in a confined space and it is still installed but all I see is a flat plate and a plastic loop, does that make sense?

 

[SHX669]

Yes the big black wire just passes through the loop . there is a "bullet " connector for/on the black wires somewhere close to the Ammeter that you can unplug if you don't want to cut the "loop".
You can remove and replace the ammeter without removing the gauge cluster/ speedo assembly you just have to lay on your back and wiggle around a bit to get good access and to see what youre doing. There are two screws that hold the ammeter to the cluster- i think they take a 1/4" socket to fit the head of the screw .
Actually the 'cluster/speedo" isn't that hard to remove in case you aren't able to acesss the new voltmeter - I've done it both ways.

 

[Steve83]

...is it possible to replace the ammeter without removing the cluster from the dash?

Maybe, but it's a LOT easier to pull the cluster for the rest of the job. Click this & read the captions in the photo album:

...one powers the the cab functions...so it needs to be connected to a constant 12v source.

Think of them as 1 wire, because that's what they are. Neither is "connected to" the ammeter; they just pass through an inductive loop on the back of the meter, as this diagram shows:



The loop isn't actually plastic - it's metal, but it's dipped in rubber to insulate it. If you disconnect the heavy wires (withOUT disconnecting the battery), at least one end is still hot. If you then slide the male bullet through the loop, it could short against the bare metal of the cluster. The rubber coating reduces that risk slightly.

What is the best thing to do with these two wires once they are removed from the ammeter?

Splice them together permanently. The connection is a weak point in the circuit, and after the ammeter is gone, it's unnecessary. So the best thing to do is cut off the connectors, and butt-splice the wire ends. Solder & heat-shrink would be best, but it would require a hoss soldering iron to join such heavy wires. A small torch would be better, but more dangerous. A crimp butt connector would be quick & easy, IF you have a tool to crimp one that large. This one might do it with a yellow butt crimp:



...but the ones being sold now are apparently lower-quality than they used to be.

Your entire install should follow this diagram:

Should they be connected to anything in the cab?

Not really. Technically, if their terminals are very clean & solidly-connected, and you know what you're doing; you could use them to power cab accessories. But if any of those conditions is NOT met, you could burn out the fusible link or cause other problems. So it's best NOT to try to use that circuit - just splice the ends together & seal it up.

 

[DirtDonk]

What they said.
As for access, another popular method for servicing the cluster is to remove the driver's side air vent from the cowl under the hood. Once that's out, you can easily get to the back of the cluster as it's right there.

But if you're still young and flexible, you can do it on your back. Personally though, I only like to do that when I remove the driver's seat, so likely I'd just take the whole cluster out and let it sit there hanging under the dash or sitting on some sort of support stand while you work.

Heck, you could probably just leave the ammeter hanging off the wire if you needed to. But since that plug is there for this very reason, go ahead and use it. It's a good idea to pull it apart when working under there anyway, to inspect it for rust or any other problems.

And take what Steve said to heart. That Black w/yellow wire IS your main feed that everything else takes power from. That's your "charge loop" if you will, where one end is (or used to be in your case) on the back of the old alternator and the other end is at the starter relay. It's how everything is powered and how the battery is charged.
So yeah, it's pretty important to leave it intact or splice it permanently like Steve suggested. As said though, if the connector looks to be in good shape, just keep it as is and make sure it's plugged back together nice and tight.
Since it's only powering your cabin accessories now, and no longer has battery charging duties, it's load is reduced. This is assuming you now have the larger 6 or 4 gauge cable from the alternator to the battery?

As for powering the new volt-meter, don't bother with the big Black wire. Simply take the power for the gauge from the input side of the IVR, or from the stud on the back of the ignition switch. Both are very convenient to the gauge, with the IVR literally being there to power gauges already, and only with the key in RUN.
Just don't use the normal output side to the gauges. Use the input side from the ignition switch.

Paul

 

[latrucker]

Wow!!!

Steve....when you answer a question you go above and beyond. That is exactly what I was hoping for and more, you even answer questions I hadn't asked yet...lol. Big thanks to you and anyone else who chimed in. Gotta love this site...