I do love this forum, you guys have been a tremendous help. I’m still scratching my head with this, so maybe you can still give me some direction.
Here’s what I can relate… 1) ’50 3100 2) Converted to 12v system. 3) Fuel gauge is 6v. 4) Entirely new wiring harness. 5) Gauge is original (as far as I know). 6) Gauge has always worked (for me). 7) But I don’t know if gauge ever worked accurately . 8) I’ve never paid attention to it, never had more than a couple gals in it. 9) Sending unit is 30 ohm, …”30 ohm” stamped on unit. 10) Checked Sender with Ohm meter, checked good at stops …0 ohm empty, 30 ohm full. 11) Float Rod moves freely “stop to stop” and is basically straight (as found) 12) Float is completely buoyant. 13) I’ve made every effort to loosen & re-tighten all electrical connections.
I’m working on the assumption that I have it all wired correctly because it appears to be functioning correctly except for the fact that when I move the float manually to the full up position, the Gauge only registers 1/2 full.
From the full up position (of the float) the instant I begin to move it (from full up), the Gauge begins to move down (from it’1/2 full position).
Now, (for reference) let me back up just a bit, before doing these tests with sending unit installed in tank and tank is 3/4 full, Gauge registers 3/8 full, as in photo "C"
Returning to the “bench test”; while doing these tests, the sending unit was setting on the seat of my truck, the only (2) wires connected to it were the same as it is in photo “B”, 1 wire connected to the terminal fitting/stud and the other wire connected to the sending unit flange.
Again….it appears to function properly except that for full up travel of the Float, the Gauge only registers 1/2 travel.
Can’t think of anything I left out, I don’t know what else to do, maybe you can help…. I’m all ears. Thanks, Jim
