Gas gauge

[fatride]

After a couple of panic stops to check my brakes I noticed that the gas gauge is not working. It reads full all of the time, No amount of wggling wires or tapping the dash will bring it back. I have cleaned the ground on the tank and plugged and unplugged the sending unit wire. Would the panic stops have anything to do with it not working all of a sudden? Maybe the quick stop jambed the float hard enough to damage something?:confused:

[bobs409]

Sounds like trouble with the fuel gauge wire that runs from gauge back to the sending unit. Maybe wire is broken or bad connection.

[bubbletop61]

Thought I would jump in on your post with another question that might help both of us if someone on this board has some info. I am trying to restore and test the instruments before installing in the dash cluster.

When I apply 1 volt to the gas gauge it goes to "E". This didn't make sense because most gauges go to "E" when the ignition is off, therefore no power applied ( I think???) I am thinking that this is because the voltage is applied with no resistance. As the resistance increases from the sender unit, does the gauge move from E toward "F"? Any thoughts on this guys?

This is a great site and will be a great source of info as I will be heading into a 348 hi-horse rebuild soon. Thanks to the founders and glad to be on early.

With Best regards
Gar Gibb:cheers

[fatride]

I took the tank sending unit out and it is broken. I had another one from my parts car and after trying it out I put it in. now that one doesn't seem to work right and it's leaking from someplace. I can't tell if it's the rubber hose or a pin hole in the steel line. Well my question is, can I solder this flat copper wire together or will it somehow effect the resistance in the system and give me an incorrect reading at the gauge?

[fatride]

I soldered the wire together. I have an ohm meter hooked to the gauge. The range of resistance I get is from 31.1 ohms to 00.9 ohms. Does anyone have a tank unit that they can test so I can see if my readings are compairable ? :D

[tripowerguy]

I've got a brand new one out in the garage as soon as I get home from work I will test it and tell you what it is. Roy

[tripowerguy]

I ran out and checked it before I went to work. Mine tested .1 to 26.0 I lifted the float several times and I had a variance of 23 to 28 as the top number. Roy

[fatride]

Thanks tripower
Looks like the solder job did no harm. I would think a difference of a few ohms would not effect the reading at the gauge.:D

[bubbletop61]

Thanks Tripower and Fatride.
I would agree that the difference of a few ohms, in this range of almost 30 ohms should not effect the operation too much. Your information gave me the piece I need to test the works of my fuel gauge which is responding nicely to the change in resistance. Thanks for the help. Now I need to figure out the Temp gauge.
It operates on a change in Magnetic field it appears, between the two e/m coils. The needle is returned to Cold position by gravity
(counterweight on the needle pivot shaft), but is actuated toward hot, I assume by the H field??? There are two magnetic pointers coming from each coil toward the counterweight on the shaft, which I am guessing represent magmetic poles??? But there is a third point that comes from the chassis of the unit, that extends out under the counter weight and appears to be trimmable...
A calibration element?? Or just a ??? Anybody know anything about this??? Thanks again for the help.
Gar

[fatride]

The tank sending unit from my donor car works good enough to use. When I installed the tank unit I had around 5 or so gals maybe more in the tank. The donor tank unit read like a 1/16th tank. I put 11 gals in the tank yesterday and it reads a little over half a tank. So this will give me a little cushion, when the gauge says empty I'll have at least 3 gals in the tank. Somehow I think I would be better off not knowing that! :D

[tripowerguy]

Yeah, your always going to see it on empty and think I can go another few miles. One day you'll guess wrong and be walking. Roy

[bobs409]

I had a '68 Impala that never had a working gas gauge. Used to take the cap off and shake the car while listening at the filler neck. Slosh-slosh mean't lots of gas and trickle-trickle mean't getting low! :D Got pretty good at it and only ran out of gas once and that was going up hill. Walked for 5 gallons, came back and it still wasn't enough because if it being on such an angle! :mad:

Oh the days of being 16 again. Too scary to think about. :eek: