the new fuel gauge story

Part 1 : after 2 years of tests and spending money for nothing, after discussion with a friend I decided to use an independant battery to fix a good fuel gauge.
I bought a new gauge, as we can see there is a screw to put the needle at low position when it is really low. It is useful.
Then I'll test my gauge with my small battery, stopping the main battery to avoid possible problems.
I know that the sender unit works, so it will be clear for me.

Then what to do? stay with the small battery or connect the gauge to the main 12v battery.
Not clear again. I don't want to buy new fuel gauges permanently. There is some electronic inside to transform into 5v this ohmmeter/ fuel gauge, and if wrong connection, dead. It is very sensitive.

 

Hmmm...you've been struggling with this for quite a while haven't you? I don't know the intricacies of exactly how the gauge works but have never had any problems actually getting one to function as it should, so let me try & help....If the battery you have in the picture is 12 volt, it should work OK....first thing I would do is take a small screw & nut & run a ground wire from one of the mounting holes on the gauge to the negative terminal on the battery...next I would take & run a wire from the terminal on the back of the gauge (I think it's marked "S") to a "new" fuel sending unit, then put in another screw/nut & ground wire from the sender mounting plate back to the negative terminal on the battery....when you have all that done, you're ready to put power the the gauge...when you run the wire for power, you should be able to pick up the sender & move the float up & down & see the fuel gauge move from full to empty....

ETA: I would forget about trying to adjust the screw that's inside the hole on the gauge....If your gauge doesn't measure the level of fuel to your satisfaction, it's best to bend the arm of the float to get it to where you'd like it....

 

I don't think that fuel gauge has any mounting holes on it so I would put a metal hose clamp around the housing with two ground wires clamped under it. Connect one ground wire to the sender outside metal housing and the other ground wire to the negative terminal of the battery. From your picture it looks like the fuel gauge swings from left to right. That is the opposite of the stock early jeep. Now connect another wire from the "S" terminal on the gauge to the center screw (stud) in the middle of the sender. Now you are ready to power it up. Connect the Positive lead from the battery to the "I" ignition terminal on the gauge and you should get gauge movement when you move the arm on the sender. This movement is slow moving so don't get in a hurry. Let us know how this works.

 

Good catch Walt & great idea on a ground...