Fuel gauge / sender puzzle

[tailwind22]

The fuel gauge on my 77 backdate seemed to have stuck on 3/4 full. I pumped all of the gas from the tank and the gauge reads 3/4 and the low fuel light is on. I am guessing the issue is the gauge as the sender would be the source of tripping the low fuel light and thus working? Thoughts?

[blucille]

Sounds like a bad sender to me.....the low fuel light operates separately from the fuel level signal to the gauge. Sometimes it’s not really the sender at fault, it’s a slightly bent mating flange in the tank, could be caused by denting the bottom of the tank....

Best test is to remove the sender and turn it upside-down, this will show if the sender is operating normally out of the tank.....sometimes the wire that the float rides on has some rough spots high causes the float to stick at that spot.

[76FJ55]

Un plug the sender and then turn the key on. The gauge should read employ, but the low fuel light will not be lit as it will also be disconnected. If it still reads 3/4, the problem is either the gauge or wiring.

[tailwind22]

Thanks, I'll give these a try.

[tailwind22]

Closing the loop here. Took the sender apart and found one of the three single strand wires that run from the top to the bottom had severed. Stripped a 12 gauge wire to get a single strand that I then soldered back in place and had a working sender.