Hello All,
Belonged to this site years ago. Changed computers and web carriers a few times and lost my paper work. Question: I have a 1963 uni pickup. Been working on if for a few years. I just took out the cab gas tank and installed a 1965 mustang gas tank in the rear between the rear frame rails. Using original dash gauges. Ran new hot and ground wires to the tank. The test light showed I have pulsating current. Only thing is gauge does not work. Do I need to buy a new gas tank sending unit? since I never pulled it out of the tank? I thought that since there was a two year difference between the model years it would work. Thank you for some guidance on this issue.
If you still have your old sending unit you can plug it in and move by hand to see if it works.
or ground the hot wire and it should make the gauge move.
Try grounding the fuel rank sending unit wire to the frame. Gauge should go to full. If it does, the sending unit is likely bad. If it doesn't, the gauge is likely bad