Question about 1983 Jeep CJ7

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1980 CJ 7 Fuel gauge/ sending unit issues

I bought a 1980 CJ 7 and the fuel gauge doesn't work. Long story short the tank was bad and I figured so was the sending unit. I now have brand a brand new tank & sending unit and hoses clamps etc. Everything is disassembled and off of the vehicle. I noticed during the tear out portion that there were two wire coming off the old sending unit I assumed one was a ground because it was grounded to the frame, the other lead must be low voltage or positive lead that goes all the way to the dash gauge??? I didn't find anything that it would have been connected to? I know the dash gauge must have some lead going to it from the sending unit?? I am better off jut running a brand new single lead all the way up front? Is there a lead that goes all they way up front and I am not seeing it?

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  • kenwed May 31, 2009

    Need more HELP. I have a new brand new fuel gauge and new sending unit. I decided to do a little test just to see if they were compatible or not. I hooked up the gauge to the positive and ground wire connections, then ran a separate line to the sending unit and also grounded the sending unit. When I turned on the ignition the gauge went to 3/4 full right away and the ball on the sending unit was in the empty position, as I moved the ball the gauge went to full as it should but it would never went down to empty only 3/4 full...What am I doing wrong???



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There is a lead that you must be missing. but given its age, i would run a new wire. the gage should have 3 wires out the back. positive , negative, and the signal wire.

Posted on May 27, 2009


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