C1: Fuel guage

[Dave F.]

Since I've owned my '59 (2 years now) the fuel gauge has always read just under 3/4 when tank is full. Lately it has crept down to where I'm lucky to read over 1/2 tank when it is full. Is this the gauge, or I'm I going to have to pull the darn tank?

-Dave

[Dave F.]

Re: C1: Fuel guage

When I searched the archives I couldn't find an answer to my particular problem, but in one post someone said "There is a good article about C1 fuel gauge/sender problems in the December 2004 issue of the Corvette Enthusiast magazine. It is in the section called techbench and the author is John Hinckley"

Does anyone have this article that they could post? I looked online and I don't see that they sell back issues of that magazine, but I can check with customer service tomorrow.

-Dave

[John O.]

Re: C1: Fuel guage

Hi Dave

Like I did on my 62, add a second ground wire from the tank to the frame. Also it sounds like you may have a pin hole in the float and the float is filling with gas, keeping it from giving you the correct reading. If your tank is the same as 1962. Take the gas tank cover off and the sending unit is right there on top of the tank. If niether one of these help, it might be time for a new sending unit.

Good luck...John

[Christopher R.]

Re: C1: Fuel guage

Sounds like a sender problem. Sounds like the float is getting waterlogged. You need to take out the sender; remove the float; and, shake it next to your ear. If it has gas in it, you need to buy a new one. (probably a new shirt too.) You can also test the float by putting it in close to boiling water and see if bubbles come out. But your wife won't be happy you put that dirty thing in her good pan.

The usual Corvette vendors don't sell the float separately from the sender. But you can buy the float separately from Chevy vendors. It's a common part. I know 55-57 Chevys took the same float. I'll bet many other Chevys did too.

[Dave F.]

Re: C1: Fuel guage

Thanks John.

-Dave

[Dave F.]

Re: C1: Fuel guage

Thanks Chris.

-Dave

[John H.]

Re: C1: Fuel guage

Dave -

Use the link below to go to Barry K's site, scroll down to "Gauges and Instruments", and you'll find the article as "C1FuelGaugeTech.pdf"; you can left-click it to read it, or right-click it to download it.




C1 Fuel Gauge System Diagnostics

[Dave F.]

Re: C1: Fuel guage

Excellent! Thank you very much John.

-Dave

[Dave Suesz]

FWIW...

I have rebuilt the sender in my '55, and the float looks just like the one in my '66 Mustang. You can get that float new, too.

[Rob M.]

Re: C1: Fuel guage

Dave,

Just make a small hook out of an old wire close hanger and pull the float up while it is still in the tank. The full guage should read full when it is completely in the up position and empty when it the float is completely at the button.

If not you might have one of the following problems:

1) variable resistor on the fuel sender unit is malfunctioning
2) corroded/bad contacts on the fuel sender unit or back on the guage
3) bad ground on the fuel tank or guage cluster
4) badly calibrated guage (unlikely)
5) badly internal grounding (in the guage housing the guage unit should ground to the guage housing, sometimes people paint the inside to thouroughly so it doesn't ground, don't ask me how I found out, but this is not lickely your problem either since the guage is then packed on full)
6) sinking float (unlickely since it would then be lying on the button all the time since it would fill up completely and the guage would read empty all the time)

regards,
Rob

[Dave F.]

Re: C1: Fuel guage

Thanks Rob.

-Dave

[John Nuzzo]

Re: C1: Fuel guage

Over the years since my '62 fuel guage died, I tried to read all the technical articles and potential fixes. Last month I finally decided not to screw with the esoteric stuff and simply pulled out the sending unit and, of course, found a hole in the float. I believe that ZIP sells the correct float, but being cheap, I simply soldered the hole and reinstalled the unit. ALL BETTER....KISS (keep it simple, and if that doesn't work, just ignore it) John N.