Arrgh...Another gauge problem

[chitown40]

Just finished putting the fuel tank in after herc'ing the tub. Now the fuel gauge stopped working. All of the other gauges function normally. Does the fuel tank ground itself to the tub normally and by herc'ing the tub did I just unground it? That's all I can think of. My test light went out on me, so all I have is my meter for tonight. I'm getting a pulsing voltage at the sender wire (red/yel) w/ the key on, but I am not getting a resistance reading at all when I go from the red/yel wire to the white/blk ground. Anyone have this problem after re-installing their tank ?

 

[atoyot]

No the fuel tank should not be sitting flush on the tub. If I remember there are two wires going to the fuel tank one for ground and one hot. Did you get the tank lined also?

 

[nhfj40]

there should be 2 wires ground on the outside of the sender and the terminal goes to the gauge ther is no voltage thats how you blow yourself up! I had a similar problem with my gauge come to find out when I pulled the sender out the contacts were dirty cleaned them up and it works fine! I forget the resistance reading that you should have but I know that is is in the Haynes service manual the test light won't help you there.

 

[lunap]

Whats the easiest way to get to the sender on a 1980 Fj40?

 

[chitown40]

Ok, more awake now... The tank is not lined,, just the tub floor and the tank cover. The tank was in brand new condition and I just left well enough alone. There were four pads underneath the tank that cushioned it from the tub. As far as the voltage reading, there has to be a voltage at the positive sender wire, just no amperage I would guess. Anyway, I'll take out the sender again and try cleaning the contacts.

Lunap,

I have no idea if the fuel tank design is different between a '77 and an '80, but on mine I can tank out the sender just by removing the passenger seat and the dust cover on the tank cover.

Rob

 

[lunap]

Rob,

if your 77 is located under the passenger seat, inside the body then it is different. I think in 80(?) they started putting them under the body in the middle. I will have a look tonight and see if there is access from the compartment.

 

[chitown40]

You're right, it's under the body. Logic dictates that unless there is an access cover somewhere in the bed, you'll probably have to drop the tank. Then it should be right on top. I've never seen a 1979+ cruiser tank, so this is my best guess just from dropping the tanks on other cars with underbody mounted tanks.

 

[3_puppies]

I vaguely remember in my 79 a trap door bolted to the floor, 4or6 bolts, under the pass. seat. or maybe between the seats, can't remember. I assumed it was to get to the sender.

 

[wdorry]

It's between the seats

 

[lunap]

a safety question. If I am pulling out my sender to test it, or even just the terminal to test the gauge, do I need to empty the fuel tank?

 

[wdorry]

Disconnect the positive (+) terminal of the battery. Make sure the wire cant spring back and touch the terminal. If you want to be real safe take the battery out. Bill

 

[lunap]

silly question. Disconnect the pos terminal even if I want to see if the gauge works? where does the charge come from?
new to this here.

 

[chitown40]

I think he is referrring to disconnecting the battery before removing the tank. To test the gauge, diconnect the red/yel wire to the sender and ground it with a test light....light should flash and gauge should deflect.

On a side note, went outside today and my gauge works fine. I didn't change or fix anything....Another intermittent problem to add to the list.