Fuel Gauge stopped working

The sender unit in the tank of my old 75 series is simply a spiral wirewound resistor with a float operated contact that runs along the resistor to provide the output voltage. Don't know what the voltage should be - that would be decided by the gauge, but probably not as simple as 12V. In mine the resistance wire broke in the middle, the gauge read full for over half, and empty for under half full.

If your problem is the sender unit, suggest the best fix is to replace it. I actually repaired mine by replacing the broken resistance wire, but that was because I had suitable resistance wire and was interested to see if it was possible. It was possible, but it's not something I'd recommend to anyone with finite patience and time!

If you drop the tank from the vehicle (empty it first) and remove the sender assembly, you should see any obvious damage there. Unless your problem is that the gauge shows only full and empty, I think I'd explore other possibilities first.

Cheers

John

Michael,
Had the same thing happen recently in my 75ser Troopy and it was the sender unit. The resistance wire had worn through and the pickup had snagged at about mid way. Replaced the sender unit and all is well. Cost was about $200 for a third party unit which was a better design than the original. Lasted 380,000 - wonder what the new one will do?

cheers
alastair

Try to take the wire off the sender unit and earth it out, you will need some one to watch the gauge in the dash with the ignition on, If the gauge goes to full by doing this, you will then know that it IS the sender unit,

Shane

Thanks for all the replies, looks like I will be replacing the sender unit.

Regards
Michael