Fuel Gauge not working, but was?

Hey Gang,
Well, its 22 degrees this morning and the cover is on the 79B, but a nagging not working fuel gauge that would go unsolved till spring gets the best of me, so thankfully my garage has a heater, so I fired it up and pulled the cover and here are the facts:

1. Last week the Fuel gauge worked fine.
2. All other gauges work.
3. Did nothing near the sending unit.
4. Did replace a cooling fan that was bad and had blown the fuse. (replaced fuse, of course)
5. Frustration level high.

Any help solving my problem would be much appreciated.
Ken


Note: Still in love over new purchase of 79MGB, pictures when time cooperates, which will be in (8) eight working days when I retire. Yahoo!

Mine "sticks" all the time, I just give it a tap with the finger and it springs to the correct level of fuel. You probably whacked it a couple of times already...

Same thing just happened to me with the GT. Found a short at the push on connector to the sending unit. Looked fine, but no voltage passed through. Cut the wire short, put on a new connector and voila, the gauge worked again

Greg,
I just did the same thing, but with no results, condition unchanged.

An update. I checked and have 12volts at the green wire on the back of the fuel gauge and 12 volts at the green wire on the voltage stabilizer.
Ken

You should have 12 volts at the "B" terminal on the stabilizer and about 10 volts on the "I" terminal which feeds to the gauge. With the engine running, check your voltage at the gauge terminal. If you're OK there, then your float might be suspect.

I have a replacement gauge if you need one, but they're pretty rugged, so I suspect it's electrical and not the component itself. Is your temp gauge working?

Have you grounded the Green black wire on the sender to see if the gauge goes to full?

Dan,
I have 12volts on the
B terminal and 9 volts on the I terminal.

Paul,
It does nothing when I ground the Green/ black wire after removing it form the Sending unit.

Also Temp gauge is working fine.

Ken

Another update. I thought about sanding a clean surface on the frame thinking it might not have had a good connection to ground. I was right. After crimping a male spade connector to a wire and plugging it into the sending unit green/black wire and clamping the bre end of the wire onto the bare spot on the frame, I went to the ignition and when I turned on the key the fuel gauge went to near full which is where I think the fuel level is. Now what?

So does the above post prove the sending unit is bad or the fuel gauge is bad? When the green/black wire was removed from the sending unit and grounded, the fuel gauge went to the full level.
Ken

The sending unit Ken but also check the ground on it.

Thanks, Paul. I have ordered one this morning with a lock ring and rubber seal.

what a bunch of nice people.............only here..........a new party the EMG party, problems solved.