The Stovebolt Site Forums The Shop Area The Electrical Bay I have a gas gauge problem

Did a search,and all the gas gauge problem. So I apologize for asking again. Been working on a 1949 1/2 ton installed a 235, a complete wire hardness for 12 volt put in a new sending unit and 12 volt gauges, had the tank out and cleaned it. Just now got to the place I could put gas in, was mainly looking for any leaks in the line connections. Put about 4 gallons in , turned the key on and nothing, no movement at all, gauge stayed on E, Took a test light reached up touched the E post to ground got light with the key on. So I took out the sending unit and tested with an ohm meter, tested ok. My question is I touched the E post with the key off to ground a complete circuit , touched the sending post to ground a complete circuit. Also tested the sending wire at the tank with it disconnected from tank a complete circuit to ground . By the way the hot is connected to the Empty post .Test the tank to ground good , have a wire to ground. Is it possible that the E post is taking the 12 volts straight to ground? Any help much appreciated ! Thanks

This post, thanks to Volfandt, should help explain how the gauge should work. [Click]

I see you put in a new sending unit BUT is the sending unit for 12 volts, if not it needs a resistor I think.

Senders are not voltage specific


He stated he has 12 volts and a 12 volt gauge. No resister needed.


If this is a new 12 volt gauge there are 2 common issues to check.

Good grounds, and clearance at the needle. The reproduction 12 volt gauges have a needle that sits higher than original. Sometimes it get pinched by the bezel. So check for clearance.


Another common error is the ground. There is a metal tab on back of the fuel gauge with a solder glob..this need to contact clean metal in the cluster. If you refurbished the cluster and painted it you'll need to clean the paint off so the back of the gauge touches metal


Let us know what work you have done to this gauge. There is more troubleshooting to do.

Going to have to pull the gauge again. I pulled the sender unit again and hooked it up to the sending wire and with the key on, moved the float manual nothing. And I know I have power to the E terminal, so the gauge is not grounded ,or I have already smoked the gauge.

Did you ground the sender for this test?
Sender also need to be grounded even for a test.

If the gauge was properly grounded but the sender was not the gauge would go to full.

Not fun pulling the gauge in and out the dash

The sender was grounded, maybe the gauge is not, I've never had the needle move at all . I know the gauge is no fun to pull ,but better now then latter, I want the gauge to work .Maybe the needle is stuck on the bezel. Thanks

I've mentioned this before, but before I even thought of trying to get the original gauge to work, I gave up, and just use my Fluke meter to check fuel level. It actually works very well since it's so accurate using 10ths of and Ohm. You can calculate fuel mileage even on short trips. On a 17.5 gallon tank you just read the ohms, and multiply it by .583333. Tells you exactly the fuel level in gallons. Pretty much how they do it on new cars.