Fuel gauge problem.

[chrisdebois]

Hello, I bought a second hand fuel gauge and fitted it, but when I turn the ignition on it reads half full all the time - even when I disconnect the cable from the fuel sender?

I would be grateful of thoughts.

Chris.

[bmcecosse]

Age of car? Colour of gauge ? Colour of speedo? Does it jump up to that reading - or just slowly move there? What does it read when not connected to anything? And what was wrong with the old gauge anyway?

[chrisdebois]

Hello. It is a '64 car with the gold surround. It reads empty when disconnected and jumps to half full when connected. The car is a distance away so unsure about the colour of the fuel gauge. I put this in last year and have just re-read my old post which said that the other gauge was stuck on full all the time. I think that one jumped to full - certainly didn't slowly move in to the that position.

[bmcecosse]

Ok - so it it's not the black 'hot wire' gauge. It should go straight to Full when you connect it to 12 volts - so I guess the needle is sticking. If you have the tank sensor there - then obviously if connected through that it should swing up and down as the sensor moves. The old gauge sounds as though it was working correctly? But the tank sensor may be faulty.

[chrisdebois]

Hi - I had a look this afternoon after a mechanic said to touch the cable that attaches to the sender unit to earth and see what happened. It flicked quickly back down to empty?

[bmcecosse]

The polarity is wrong - change the wires on the back of the gauge.