Re: 1937 120 Conv. Sedan - Blanche

Posted by TxGoat On 2024/5/13 17:07:32

The gauge unit in the dash is a low power device with high internal resistance. While you will have full power at the switch terminal of the gauge with the key on, 6 volts+), the amount of power from the sender terminal on the gauge to ground will be much reduced. The gauge unit should have a specified DC resistance in Ohms, but I don't know what it is. The sending unit's resistance will vary with the fuel level within a specified range. A very small 6 volt bulb, like a dash light bulb, might glow if it was connected to the sender end of the gauge wire and grounded, key on, and the gauge would probably show a reading. If your dash gauge shows continuity on an ohm meter with the sender disconnected and the key off, it's (probably) OK.

When I turn my key on, my gas gauge moves up to "empty" and stays there until I turn the key off. My guess is that my float is missing or full of gasoline, or that the sender is defective.