newbie, trying to fix fuel gauge

hey everyone, first time posting but i have been lurking around reading a lot lately.
i have a 1962 ford falcon window van. the wiring is a huge mess, all cut up and spliced all over the place. it runs and drives fine though. i had to wire up the turn signals and now i'm working on fixing the fuel gauge. its after market and not sure how to tell if its a 73-10 ohm one or not. but i know the fuel sender works cuz i tested that full tank reads about 68ohm. my question is, how do i test the gas gauge to see what ohm it is and also, i figured out how it wire it in to the harness, without the ground wire attached to the gauge reads full, when i attach the ground to the gauge it drops to empty. the tank is full right now though.

any help is appreciated in diagnosing my problems.

thanks a lot

-hill

Welcome Hill,

Not sure if it will help but I did a diagnostic thread for Econo fuel gauges a while back:

https://vintage-vans.forumotion.com/t14006-fuel-gauge-sender-diagnostics

Maybe it will help. Turns out grounding is the main culprit but there is a logical sequence to follow to get to that conclusion.

Hope it helps,
George

Welcome to VV!!!

Welcome to VV hill. Can't remember how to test the gauge. I no it's only a 6 volt gauge and some one in here posted before how to test them, and I'm sure they will chime in. be sure to post a pic so we can see what your working on.

The way I test them is to remove the sending unit wire at the dash on the gauge itself, turn the key on, and touch a ground wire to the sending unit side of the gauge. The sending unit is really just a variable ground. So when I see the needle come up completely to full, I know that more than likely the problem is the sending wire and or the sending unit side. The idea of the resistor to the two gauges is to slow down the movement of the needle, if you watch it sometimes you can see the needle pulsating.
The top of the gas tank is supposed to complete a ground to the truck, so don't do what I did one time and put weatherstrip there, its supposed to be raw metal for a ground for the sending unit. I some times solder a spade connector to the sending unit and simply connect a ground wire to the frame if I have a problem there...
Old Skool

BTW,,,,, NO GOOD PICTURES till Friday or so,, BUT,, finally have the new replacement idiot lights done for the gauge cluster. EXACT SAME FORD SCRIPT,,, done in lazor writing for all three. ALSO,,, the green turn signals are cut to fit inside the small cardboard exactly as well as both blue and red for the high beams, depending on what color yours used or you want. Also, the idiot lights come with new cardboard pieces in the kit. Will get some pictures ASAP..
OLD SKOOL

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