New 12 volt sender and fuel gauge reading full. Took out the fuel sending unit, measured gas 1/2 full in tank, checked ohms 12-48. Checked sending unit and gauge in front of me and gauge read full when sending unit was at was all the way up, and gauge read empty when sending unit was all the way down. What do you think the problem is? Bad ground or sending unit or ??? Thanks for all the replys. Chris
usually when it reads full all the time it is a bad ground or none at all . that truck looks just like what i am working on .
bad ground or connection, if it bench tests ok. or...is the sender hitting something in the tank? at 1/2 tank, the ohm reading from sender in tank should be 30
Fords use King-Seely gauges which need the matching sender to work properly. They will not work accurately with an aftermarket sender. Use the OE 6V one with a volt drop.
If your sending unit is secured to the tank with several screws/bolts just add a wire to one of the bolts and run it to the frame. If it is held in with the locking ring what I do is expose a 1/2" of wire and hose clamp that to the fuel outlet (like on mopars) and run the other end to the frame. Every old car I get the first thing I do is add an extra or redundant ground to the fuel sending unit. If the gauge/fuel sender works off the car but not while in the tank...is your float arm binding at all so it reads full all the time? Is it "clocked" correctly in the tank so its not getting hung up on the side of the tank? I ask because I ran into this problem on an OT car after a fuel pump replacement and it was a matter of changing the fuel pump "clock" from 12 to 1...
The Jalopy Journal
