I have a 12V '56 Chevy gas gauge in place of the 6V one in my '53 Chevy. I also put in a new sender and tank. I ran a separate ground wire to the sender. All worked perfectly for a year. Now, for no reason, it reads 3/4 after a fill up, and reads 1/4 when AROUND empty. My Dad's '56 had this problem, then he put in a digital dash (Dad's old, but not old school), now the robogauge reads correctly. Was this self fix a coincidence, or did some wire jostling correct a wiring problem at the gauge? What should I be looking for?
This sender has the plastic float. If the arm was bent up, it would still go all the way to "E". If it was bent down, it would still go all the way to "F". That's assuming that I've left the car somewhere that this could even happen. Seems like the sender is sending half of the signal, or the gauge is only reading half the signal. Why would this even happen?
Because the tank was allowed to sit dry until dried gas is all over the rheostat windings. Try cleaning it off gently. Does your state have ethanol in the gas?
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