Fuel sender unit

[RollyTG]

I am about to install a new left hand fuel tank and testing the new sender unit before putting it in the tank shows that it works, but in reverse. When the float is in the fully up position it shows empty. Surely that is not right. Could it be that this unit is for a negative ground car and mine is positive? If so can I just reverse the wires at the gauge? If I do that presumably the right hand tank will then be reversed??????? Any advice welcome.

[John Quilter]

I do not think that is the issue as many years ago when I converted my car to negative ground there was no issue with the fuel gauge readings.

And FYI, from my Morris Minor experience, at least for those cars, there was a change in the gauge and sending units which reversed their function when they went from an earlier gold faced gauge to a black gauge circa 1963. Could there be a similar change in the sending units for Jaguars?

[RollyTG]

Thanks John. You are right, that is not the issue. The problem has been located - it is in the mind of the operator. I was looking at it upside down. I wish they were all that easy.