12 volt

I have been helping a member change his 47 sedan too 12 volt, it is now negative ground. How do you get the gas gauge to read right?? It is reading backwards. I have tried swaping the wires but no change, I tried swaping the wires on the voltage reducer, no change. Do i need to swap the amp guage wires?? I know it will read backwards, but we would rather have the gas gauge read correctly.

For the most part--12 volt has little or no effect on the fuel guage--Been doing it for years.When changing from - to + the amp gauge will read backwards.Just reverse the wires on the gauge(amp). I am planning to add a small 6 volt battery with a push button for the gas gauge on mine when I change to 12 volt negative ground.

That will work but it's a lot of unnecessary extras.

We have a voltage reducing regulator (not just a resister) that attaches to the back of the fuel gauge to regulate the voltage to a steady 6 volts and make the gauge read correctly.

The correct way (IMHO)is probably cheaper also.

Butch and Fonda Williams, Service Motors, 1-574-664-3313, www.servicemotors.net

why? The gauge reads ohms, not volts or polarity. 6 volt, 12 volt it doesn't care. If it reads backwards then the float wire is bent the wrong way. I had a fuel gauge problem also. I put in new gauges and the gas gauge was not properly grouinded to the panel, when it was reinstalled. I could bump the dash and it would jump up to full. But when the key was turned off it would go down and stay, even after the key was back on.I pulled the gauge assembly back out, removed the gas gauge, cleaned where it mounted and put everything back in and it works beautifly now. Problem solved.