UPDATE Calibration of Gauge & Fuel Sender 67

[Al R.]

Finally was able to get around to checking the fuel sender and gauge today on the 67. As you may remember, it would only read 3/4 full when it was full. Anyway, the ohm readings were .4 and 89.7 ohms, so this is mighty close. Not sure if it is close enough. I was not able to see the position of the float arm in relation to the upper and lower stops on the unit, but do know the float was against the bottom of the tank and was pretty sure it was against the top also. (Used a homemade device to pull it up fully). As a side note and as luck would have it, the gauge now will only read 3/4 full, regardless of what you do. I tried shorting the brown wire to get it to read full and it would not move. I also cleaned the sending unit ground lug and the ground wire terminal w/o any success. The tank has approx. 1/4 or less fuel in it. Thinking at this point maybe the gauge, since it has quit working. Any thoughts?? Al

[Joe R.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Al,

How long have you had the gauge and is it new or an original gauge? If it's a new gauge and doesn't work maybe the manufacturer will warrant the gauge. I suggest you send it back to the supplier and see if you can get it replaced under warranty.

JR

[Rob V.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Hi Al--

I had a new Quanta gas tank and sender unit kit, (of unknown manufacture), installed in my '67 Coupe one year ago. There was nothing wrong with the tank and sender unit that we removed; but it was rusty, and with my typical luck, if we replaced the original tank I figured it would start leaking in short order. Bad move. The Quanta tank fit ok, but the "new" sender unit would read in between 3/4 and Full when the tank was filled to the top. I drove the car in this annoying condition for one year until the tank started leaking at the sender unit. I pulled what I believed to be the original, (or very old), sender unit from the old rusty tank, as it always read correctly, and took it to the shop that had installed the new tank and sender unit. They reported that the "new" sender unit seemed to be not as tight a fit as the old unit which I provided. Now my wife is happy because the tank is no longer leaking and stinking up the garage and house; and I am happy because my fuel gauge is once again reading accurately. The point to my long winded story is if you have the original GM sender try and use that, or repair it as necessary. Good luck; I empathize with your situation.


Rob

[Jack M.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Perhaps this technical article could be of some assistance: CLICK HERE

[Al R.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Hi Joe, yeah it is a new gauge. I'm going to try to pull it out asap and get it back to the supplier. Rob, I had the original sending unit rebuilt, but with the ohm reading reading correctly, I'm thinking maybe I got a defective gauge, which does happen. I learned many, many years ago just because it's new, doesn't mean it is good. Thanks for the responses. Al

[Joe R.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Al,

Just received the new gauge that was installed in your cluster back sometime in 2011. I have checked it with a Delco sending unit that I check with all fuel gauges that enter the shop. The fuel gauge is in excellent shape so we won't have to ask for a replacement from the supplier.
I would suggest that you either fix the wiring or the sending unit as one of those have to be defective since the fuel gauge is in perfect working order. Below are posted some pics of your gauge and the sending unit I used. And as you can see the fuel gauge goes to full. Maybe a little past with a stock sending unit.

Good luck with your quest,
Joe RayDSCN4246.jpgDSCN4247.jpgDSCN4249.jpg

PS, The gauge is being returned via USPS Priority Mail Today.

[Ken A.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

Joe knows his gauges!

[Al R.]

Re: UPDATE Calibration of Gaage & Fuel Sender 67

still wonder why the gauge stuck on 3/4 full even with all wiring disconnected and would not move in either direction for me w/ or w/o the wiring connected/ disconnected. As previously said the wiring harness is new and the sending unit checks good with the ohm meter. As my wife says, she did not name this car CHRISTINE after the Steven King movie for nothing. I hadn't plan to mention Joe's name, but he let the cat out of the bag. I have nothing but praise for him for standing behind his work and trying to make sure everything he does is correct and that he has satisfied customers!! Will just have to keep looking for the source, hopefully it's something that 's just been overlooked. Will start with the wiring harness, since the sending unit checks out OK. Oh well!!!