So, I had seen somewhere over on FTE there was a guy who does this, and I decided I would try it myself, since I had an extra cluster full of gauges I picked up to have spares. I bought a Cen-Tech analog voltmeter from Harbor Freight for $8, and went to work.
The only tools I used were a Dremel, a soldering iron, and screwdrivers/pliers. Total cost for this would be a $5 junkyard gauge (Probably 10 of them in the one yard I go to here) and the $8 gauge from Harbour Freight.
The idea is to swap a voltmeter interior into your ammeter, because I have seen people simply cut a voltmeter into the cluster where the ammeter goes, and it looks OKAY, but I really wanted to keep the stock cluster look.
First, I took the face off of the ammeter, I had to use a screwdriver to [carefully] open the plastic tabs that held it onto the gauge body.
Then I bent open the tabs on the back that hold the actual gauge guts into the body.
Next, I removed the ammeter itself (the posts just pull out of the plastic insulator) and snipped the wires off of the lead posts (tried to desolder them, but it's not solder holding them on, or I didn't have enough heat. This turned out to be a benefit because I had something to solder to when I installed the new guts). I snipped the needle off of the ammeter with scissors to put onto the new gauge.
This picture shows the entire Cen-Tech voltmeter disassembled in order on my desk. The only thing I used from this was the main part of the gauge (in the cylinder).
Next, I took the metal cylinder off. There are two magnets (that CAN NOT be reversed otherwise the gauge will be off by 180 degrees) that were shoved in between the case and the electromagnet assembly. I just wrapped a piece of Scotch tape around the whole thing to hold them on there after I took off the cylinder. I used a cutting wheel to remove the needle from the needle hub, since I wanted it to look perfectly stock, and use the original needle.
Finally, getting down to the actual modding. I used a sanding wheel to trim the legs down a bit, and a bit off the face of the gauge needle hub. This is because the gauge as it sat would be compressed by the instrument cluster front piece, and wouldn't allow the hub to turn.
I soldered new wires to the electromagnet assembly and to the lead posts. Lead posts pushed back in, and the electromagnet assembly is in the ammeter case. I just cut up a hipolymer pencil eraser and used the pieces to wedge the assembly where it needed to be.
I used a cutting wheel to trim the metal posts at the top, since they interfered with the ammeter face going back on the case.
The voltmeter hub was too far up to go through the ammeter face hole, so I used a sanding wheel to notch it a bit for fitment. I tested it with the trim on to make sure I wasn't cutting where I would be able to see it when the trim was one.
Here is a picture of the face back on, the hub trimmed, and it ready to be assembled.
I used a soldering iron to melt a few lips in the back of the face to hold it onto the case. This appears to be what the factory did when they attached it, and it was easy, so that's how I held it on. Then, I took my old ammeter needle, and very carefully lined it up and glued it on with modeling cement.
The cement is drying as I type this. I don't have my truck in Albuquerque with me, so I can't just drop it in for a test, but I know that the middle bar SHOULD be 12 volts. From my measurements, the D bar should be 10 volts, and the C bar should be 14 volts.
I'll test this as soon as I can to see how well it came out and how accurate it is. As it sits, the needle will travel WAY further to each side of the gauge than the other gauges, so I may add two pegs to keep it looking the same as the others when it's off. This would reduce the gauge's range to about 9.5 volts to 14.5 volts. But, the way I see it, if my voltage drops below the center mark when I'm driving, there's a problem, and I'll know it. I just like the idea of having a useful gauge and keeping it looking perfectly stock. I'll be repainting the needles on all of my gauges with the fluorescent orange from HiPo Parts to get rid of the classic faded/not faded line on them.
I'd love to hear any feedback any of you have to offer! I'm really happy with how it looks for only spending $13 and a few hours of detail work on it.
The only tools I used were a Dremel, a soldering iron, and screwdrivers/pliers. Total cost for this would be a $5 junkyard gauge (Probably 10 of them in the one yard I go to here) and the $8 gauge from Harbour Freight.
You must be registered for see images attach
The idea is to swap a voltmeter interior into your ammeter, because I have seen people simply cut a voltmeter into the cluster where the ammeter goes, and it looks OKAY, but I really wanted to keep the stock cluster look.
First, I took the face off of the ammeter, I had to use a screwdriver to [carefully] open the plastic tabs that held it onto the gauge body.
You must be registered for see images attach
Then I bent open the tabs on the back that hold the actual gauge guts into the body.
You must be registered for see images attach
Next, I removed the ammeter itself (the posts just pull out of the plastic insulator) and snipped the wires off of the lead posts (tried to desolder them, but it's not solder holding them on, or I didn't have enough heat. This turned out to be a benefit because I had something to solder to when I installed the new guts). I snipped the needle off of the ammeter with scissors to put onto the new gauge.
You must be registered for see images attach
This picture shows the entire Cen-Tech voltmeter disassembled in order on my desk. The only thing I used from this was the main part of the gauge (in the cylinder).
You must be registered for see images attach
Next, I took the metal cylinder off. There are two magnets (that CAN NOT be reversed otherwise the gauge will be off by 180 degrees) that were shoved in between the case and the electromagnet assembly. I just wrapped a piece of Scotch tape around the whole thing to hold them on there after I took off the cylinder. I used a cutting wheel to remove the needle from the needle hub, since I wanted it to look perfectly stock, and use the original needle.
You must be registered for see images attach
Finally, getting down to the actual modding. I used a sanding wheel to trim the legs down a bit, and a bit off the face of the gauge needle hub. This is because the gauge as it sat would be compressed by the instrument cluster front piece, and wouldn't allow the hub to turn.
You must be registered for see images attach
I soldered new wires to the electromagnet assembly and to the lead posts. Lead posts pushed back in, and the electromagnet assembly is in the ammeter case. I just cut up a hipolymer pencil eraser and used the pieces to wedge the assembly where it needed to be.
You must be registered for see images attach
I used a cutting wheel to trim the metal posts at the top, since they interfered with the ammeter face going back on the case.
You must be registered for see images attach
The voltmeter hub was too far up to go through the ammeter face hole, so I used a sanding wheel to notch it a bit for fitment. I tested it with the trim on to make sure I wasn't cutting where I would be able to see it when the trim was one.
You must be registered for see images attach
Here is a picture of the face back on, the hub trimmed, and it ready to be assembled.
You must be registered for see images attach
I used a soldering iron to melt a few lips in the back of the face to hold it onto the case. This appears to be what the factory did when they attached it, and it was easy, so that's how I held it on. Then, I took my old ammeter needle, and very carefully lined it up and glued it on with modeling cement.
You must be registered for see images attach
The cement is drying as I type this. I don't have my truck in Albuquerque with me, so I can't just drop it in for a test, but I know that the middle bar SHOULD be 12 volts. From my measurements, the D bar should be 10 volts, and the C bar should be 14 volts.
I'll test this as soon as I can to see how well it came out and how accurate it is. As it sits, the needle will travel WAY further to each side of the gauge than the other gauges, so I may add two pegs to keep it looking the same as the others when it's off. This would reduce the gauge's range to about 9.5 volts to 14.5 volts. But, the way I see it, if my voltage drops below the center mark when I'm driving, there's a problem, and I'll know it. I just like the idea of having a useful gauge and keeping it looking perfectly stock. I'll be repainting the needles on all of my gauges with the fluorescent orange from HiPo Parts to get rid of the classic faded/not faded line on them.
I'd love to hear any feedback any of you have to offer! I'm really happy with how it looks for only spending $13 and a few hours of detail work on it.
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