Fuel gauge sender gremlin.

[DavidSaw]

Hello cobra chums
I have a problem with my fuel gauge sender in my Dax-the clock itself works fine,and i have power at at the gr/black wire on the teminal of the sender,but when i connect the earth-not a sausage. But-and this was when my brain really started to hurt-when i connected the test lamp from the neg on my battery to the sender live and made a strong earth with the black wire the gauge reads 3/4 what ever the position of the float.Any other combinations.either nowt or of the clock.Help!
Thanks in advance.
Dave the confused.

[madjohnny]

Sounds to me like you've got a duff earth on the sender and when you connect the test lamp to the pos. on the sender the gauge is reading the resistance of the lamp and giving a corresponding reading. Run a separate earth from the battery to the sender and see if that cures it. Otherwise looks like a faulty sender.

[DavidSaw]

Hi John,thanks for your reply.
My sender only has 1 terminal on it,is that different to yours? the wires off the wiring loom are the same length,and both have eyes on them,making me think that there should be another terminal somewhere. The tanks ally,is that an issue? I've run earths to the batt etc. from the loom wire-nothing.

[madjohnny]

David, yeah that's right, one single stud. This goes to the gauge and the part of sender that bolts to tank (the alloy flange) should be earthed. Try earthing this metal flange, I assume your tank has an earth connection elsewhere possible there is problem with this. If you have Digital multimeter you could check out the sender, measures approx 10 ohms with the tank full & 250 ohms with the tank empty.

[DavidSaw]

Cheers John,will check it out in a bit!
Many thanks
Dave