Fuel gauge not working

[greens]

I have recently replaced all the gauges on my 135. All is well bar the fuel gauge that does not work. I have installed a new gauge, fuel tank sender unit and checked that the wiring is OK. Even when I remove the sender unit and move the float up and down there is no movement on the gauge. When the ignition is turned 'on' the needle moves to '0' (empty) and when the ignition is turned off the needle goes down past the empty mark - this is the only movement detected on the fuel gauge. Can anyone please advise what may be wrong with this set-up.

 

[deerseeker001]

Check and make sure you have a good ground.

 

[banjodunn]

Check and make sure you have a good ground.

X2

You need to ground the sender unit for it to work try a quick jumper wire from under the sender mounting screw to ground on the battery


Jon

 

[greens]

Thanks for the prompt response Gents. I will try that tomorrow and let you know how it went.
Cheers

 

[banjodunn]

G'day I should have said a quick way to check the wiring and gauge is to short the sender wire to earth the gauge should go to full


Jon

 

[greens]

G'day Jon

Yep, I tried that and it does go to full when shorted - put it back onto the terminal and no reading.

I also used a separate wire to the battery negative terminal from earth (mine is negative earth) with no result.

Thanks for the feedback.

 

[The kid]

There is one wire going from the tank sending unit to the gauge. The dash gauge must get 12vdc for the circuit. The gauge on the tanks must get a good ground usually provided be the mounting screws that secure it to the tank. The wire wound resister type sending unit inside the tank attaches to the float. I have found that the resistance can be wrong and give little to no reading. The tank sending unit sends back a variable ground resistance back to the fuel gauge. A few gator chip leads can verify whether the gauge and sending unit are matched. Good luck. -kid

Sent via Ipad2

 

[banjodunn]

G'day I think you might have got a dud sender unit it sounds like the gauge and wiring are working as it should, do you own/know how to use an ohm meter? If you remove the sender unit and clip one lead from the meter to the mounting plate of the sender and put the other lead on the terminal of the sender and lift the float arm up and down you should see a change I the resistance reading ( lower at the top and more resistance at the bottom of float travel)

Jon