I got tired of fooling with my other gas gauge set up so I bought a matched ohm set sending unit and gas gauge they are 240/full and 33 ohms empty and the brand is Autometer. The problem is the sending unit will only install one way and I have the float in the same direction as the old sending unit I had and the oem sending unit. The problem now is I have A FULL TANK OF GAS AND THE GAUGE IS READING 3/4 which I could live with if it meant when I got on empty I still had a quarter tank of gas.
I called Autometer tech service and they are insisting the float is hitting something and not letting it read to full capacity and I'm not convinced that's the problem.
I haven't tried the gauge test outside the fuel tank with the sender having 12 volts , seems unsafe to me to do that test and I don't want to take my gauge out.
Your help would be appreciated.
Thanks,
God Bless.

Claim to fame is the car was used as an extra in the movie Diner with Micky Rourke, Steve Gootenburg, Paul Riser and Kevin Bacon.

I have found from past experience with these types of senders is that you can use the instructions as a starting place for setting up the sender. In other words the amount of depth from the bottom of the sender and the length of the arm. I used a piece of cardboard and made a mark representing the tank bottom and another mark (based on your tank depth measurement) representing the top of the tank. Then holding the send so that it's bottom is setting on the top of tank line, then move the sender arm up and down. I think you'll discover that it doesn't quite cover the whole range. Adjust the depth and float arm until you're satisfied that the sender is covering the whole range of your tank and not prematurely hitting the full and empty stops.

Jeff Petersen

Thank you , I will try that tomorrow.

Claim to fame is the car was used as an extra in the movie Diner with Micky Rourke, Steve Gootenburg, Paul Riser and Kevin Bacon.

My fuel guage drove me nuts. I finally took it out of the tank and mounted it to a 4x4 sideways laying in the trounk and connected it to the guage source. (remember to ground it) I measured the depth of the tank and started moving the float and watching the guage. I was able to get full and empty by doing some creative bending on the rod. A replacement sender would read 1/4 to 3/4 as sent moving the float the depth of the tank.

I also floated the float to see how far is "sank" or set on top of the fuel to help figure it out. Seems to stay full a little longer than I wanted but I can live with that.

I refill at 150 miles and the dash indicates 1/4; it useally takes 11 gallons with city driving.....Good Luck

56 Vic, B'Ville 200 MPH Club Member, So Cal.

You don't happen to have a picture of that do you?
Mine is only 3-5/16" depth and the float is only 3-1/16" long so I'm installing a nub and it still only reads 3/4".
It's driving me nuts as well.

Claim to fame is the car was used as an extra in the movie Diner with Micky Rourke, Steve Gootenburg, Paul Riser and Kevin Bacon.

My tank depth is 6"+ at the hole. So I made the float movement the same; hitting the empty and full stop on the reostat. The replacement float assembly could move between 7-8" and leaving it as sent with my way of checking the gauge would read between 3/4 and 1/4. My "creative bending" actually shortens the length of the rod. Did the bending of the rod while holding the sender in my bench vice. Took many, many trys.

The supplier of the sender is the company that makes the replacement tanks and said it should work "as is" but it did not in mine. Their price was much "less expensive" than the others I have found. The rod to the float of the replacement and the stock rod were both 7-8" long The resistance of the of the reostat was the same for the one I bought and the original in the tank.

I took no pictures but as I remember I took a 4x4 about a foot long and screwed the sender to a side edge with one sheet rock screw, laid it in the trunk, conected the wire coming back, and used a twin alligator jumper to ground it to the tank. Slowly move the float arm and watched the guage. It takes time to move so this is not a fast process. I had about a half a tank of gas when I did this and when I was done that's what it read. The car was on level ground.....Good Luck

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Ten years ago I replaced my gas tank and like an idiot I purchased a new sending unit and being ever more stupid I threw the original one away before I installed the new one.
new one was way off, so I bought another and a few years later bought another, now the last one was the best as it reads 3/4 when full.

Just seems to me with everyone else having the same problem this would be a money maker for RE-BOP to either modify existing ones or make his own.
Put me down for one.

I think Carpenter lists one with the correct floats and resistance. Works in my '57. Also you may be able to shorten the float arm to allow more angle before it contacts the tank.

Frank/Rebop

Bristol, In ( by Elkhart) 

Starmistblue – I have “put you down for one”.

An electronic re-engineered replacement fuel sender that mimicsthe same electrical input to the gauge as the original sender did.The original King Seely sender sent on/off pulses to the gauge whichwas controlled by a point set in the sender. The original design hadnothing to do with the resistance of the sender. The fuel gauge canbe made to move using a variable resistance sender (which the presentreplacement senders appear to be) sending constant (non-pulsating)current to the gauge. My testing shows the following for constantinput (non pulsating) to the gauge:



Volts Gauge Reading

7       F

5       ¾

4       ½

3       ¼

1       E



So, you can see that there just isn't enough resolution usingconstant voltage from 1 to 7 volts. Just 2 volts difference wouldgive a reading of ¼ or ¾. The original design used 12 volts (for1956) for all readings, but varied the time it was applied to thegauge to give readings from E to F.

I am past some major hurdles in the design, but it will stillprobably be several months before I have the prototype working.However, it will initially be for 1956 Fords cars only. Ifsuccessful in selling a few, maybe I can make modifications to it for1957 Fords and 1949 – 1955 Fords.



Bill Newland

I replaced my sender recently and found when I tested the range on the gauge as DryLakesRacer mentioned. It would go to empty too early but only went up to 3/4 so I bent the stop and reshaped the arm so that the float would not hit the top or bottom of the tank plus changed the length to give a full range. After all that stupid me then discovered it had a grub screw for adjusting the arm on the rheostat which I then utilised for fine tuning it. I spent ages moving it small amounts trying to get it wright.

I'm still not completely happy with it as it reads overfull and stays there too long, but the important thing is it reads empty at the right time. Thinking about it, if I left the arm and the stop alone, and only adjusted the grub screw I think it may have been better than it is. I might get around to pulling it out again one day but there are too many other jobs right now.

That particular sender does give the full range on the gauge of my T Bird.