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Tips
Tips

fuel guage

tinman58

Jedi Knight
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Don't ask me how I know but my fuel guage does not work.
What is the best way to test it? I have a new sending unit and a new wiring harness, the guage was in a box with a bunch of other junk TR3A 1958
Dan
 
For a simple test, connect 12v to the gauge (between the B terminal and the case). With the tank (T) terminal open, it should read past full. If you short the tank terminal to the case/ground, it should read empty.

For more than that, check out
https://mgaguru.com/mgtech/electric/fg_01.htm
Although the resistance values are not precisely correct, they are close enough.
 
If you suspect the sending unit you can manipulate it with a length of wire suitably shaped to fish thru the gas cap opening and hook the arm of the sender. If the hook part is a big 'L' it can also be used to push the arm down. I use copper wire and make it long enough I'm not going to lose it in the tank if I let go.
 
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