Amp to volt gauge

[b454rat]

Saw this somewhere now I can't find it. I have a super nice big truck tach dash that has the fuel gauge in with the tach, and has an air gauge where the normal small fuel gauge will be. I want to put this in my 89 crew, but that has the volts not the amps. I'm hoping I can just rewire the amp gauge, but if not what do I need to do??

[b454rat]

anyone?

[ray_mcavoy]

Hi b454rat,

Seeing as how your truck is already wired for a voltmeter, I think it'd be easiest to swap a voltmeter into the tach cluster.

If I remember correctly, there are 3 square holes in the cluster housing behind the ammeter/voltmeter location. Two of them are used for the snap-in electrical contacts that connect the printed circuit to the gauge. The other is unused. And the position of the unused hole is different for ammeter vs. voltmeter. So swapping a voltmeter into your tach cluster would involve re-locating one of those snap-in contacts. And probably adding a little jumper wire since the printed circuit won't have a trace going to that formerly unused hole.

I'd also be a good idea to follow the printed circuit traces back from the ammeter/voltmeter location to the instrument cluster plug. Do that on both your existing cluster and the tach cluster just to make sure they both lead to the same locations on the cluster plug.

[b454rat]

I have a couple of dashs here, got looking at them and traced the wires back. They both go to the same spots on the plug, just the location of the pins on the back of the gauge is different. I think all I need to do is make a small hole for the snap connection thing and install the volts gauge.

[SCOTI]

Just swap the amp & volt gauges. If the contacts are removed so it doesn't contact the printed circuit, the amp gauge is non-existant. The volt gauge only requires a ground & 12v supply from any power source under the dash.

My 74 had an amp gauge. I got a dash cluster from Jonboy that had a voltmeter (which is what I wanted). I removed the amp gauge & swapped the voltmeter in it's place (direct swap). Since my OE clock didn't funtion, I simply used the power wire to it for the 12v supply & ran a ground wire to the chassis. Works like a champ.

[BLE 'BURBAN]

Originally Posted by b454rat

Saw this somewhere now I can't find it. I have a super nice big truck tach dash that has the fuel gauge in with the tach, and has an air gauge where the normal small fuel gauge will be. I want to put this in my 89 crew, but that has the volts not the amps. I'm hoping I can just rewire the amp gauge, but if not what do I need to do??

Is your speedo cable driven or an electronic one? I did this swap a couple years ago on my '90 burb with an electric speedo.
If it's a cable driven one, it'll be ALOT less involved than what I did.

[b454rat]

It's cable, out of a 74 C70 IIRC. I was gonna put it on evilbay, but since my crew is gonna be a gasser and not a diesel, figured might as well use it. Get some silver overlays for it, swap the air for clock or something else, and use it.

After I got looking at it, didn't look like it would be a big deal, but would rather wait and see what the experts would say. ")