1955 fuel gauge sender

Gee I'm glad I'm glad I've stirred some discussion.
Having driven the car for a couple of trips, the gauge is certainly strange now to say the least. It takes almost 5 minutes for the gauge to reach its maximum reading when driving. The drama continues but, because the fuel level never seems to drop now, which to me from what has been said already suggests that the gauge heater strip is receiving enough to keep the needle pointing to just above 3/4.
I'm about at the point of fitting an aftermarket gauge and sender under the dash.
With fuel gauge sender I took out of the car, which I think was out of an Aust 57 which used 12volt gauges in an identical dash cluster, the needle would register all types of fuel levels depending what it felt like on the day. I ran out of fuel several times with the gauges showing 1/2 a tank. The gauge displayed a full register of movement at various times and would move immediately when the ignition was turned on.
I'm more inclined to think that the sender which is a Dennis carpenter unit built for them by Stewart Warner which is for 6 and 12volt for 32-55 cars is causing the antics of my gauge now, but am reluctant to buy another sender from another source as it may be no better.
 
rick55 said:
Gee I'm glad I'm glad I've stirred some discussion.
Click to expand...
Well I learned more than I knew before. Thanks Beav for the diagram you posted in comment #4.

Something I was told a while back, before I bought the replacement gauge and sender for mine, but didn't fully understand until this thread.....

For the fuel gauge to have a decent chance of reading the sender correctly...
know they function as a *pair*, and a mismatch may likely defeat you.

The '55, '56 & '57+ each use different that-year-only electrical specs.
Ford built to their own specs, and the after-market folks build as they choose.
Some reproduction parts are intended as a direct replacement for the oem parts, with varying degrees of success.
Other reproduction parts are built look the same, for whichever model year, but are not an electrical copy of the oem parts, and are made to be paired only with the same model year parts made by that same manufacturer, with varying degrees of success.

Add in all the different models, sizes & shapes of fuel tanks & gauges and the limited inventory of:
Used, NOS, NORS, and new reproduction parts for 60-ish year old cars, confusing cross-reference information, not to mention some sellers wanting to make a sale anyway.... and you've got the makings of a real crap shoot.

.
 
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Just add to the confusion. Some years ago someone called bergmanj had a long post over at Yblocksforever about the 55 gauges. He had extensive documentation, set up, and test procedures. They were King-Seeley products, and the sender fed back to the gauge. The oil and water senders were fixed, but the fuel gauge had adjustments on both the sender and the gauge. I can't find his old post (I think it got lost in an upgrade), and he doesn't show up very often as he's now on a slow dial up connection. Googling it only brings up Willy's and earlier model cars, and some extraneous info. But what you describe is what I remember him posting if you mismatched the sender based on ohm rating. It's also a lot like what happened on my 55 when I added a variable resistor to try to center the temp gauge. The lag in the gauge was quite long, but when it settled down, it was straight up at 180, and just hitting the high line at 220.
 
Once upon a time, I created a tool for recording the position of the sending unit float full and empty positions for the purpose of comparing the positions marked on the tool with the actual sending unit.
I made it out of metal scraps and a cutoff piece of coat hanger to duplicate the float arm. I just bent the coat hanger around in a loop to duplicate the diameter of the float and made the pivot point in the same spot as the sending unit. The measurement is taken by means of a metal strip fastened to the fake float arm with a pivot point so the measuring rod can swivel. The measuring rod needs to be long enough to stick up out of the top of the hole in the tank where the sending unit goes.
I punched two holes in the top of the tool to bolt it down to the tank using the fuel sender mounting screws so that you don't need to hold the top down while moving the measuring stick (and possibly accidentally moving the tool which would provide a false measurement).
To take measurements, push the measuring stick all the way down till the fake float loop hits the bottom of the tank. Mark the top of the stick and the top plate of the tool with a felt tip pen. That represents "EMPTY". Now pull all the way up on the stick till the fake float loop hits the top of the tank. Repeat marking procedure. This will be "FULL" position of float.
Now remove the tool from top of gas tank.
Get a little clamp (paper binder clip can work too). Clamp the measuring stick to the top flange of the tool in the "empty" position.
Collect a bunch of scrap lumber and stack up as needed on garage floor or workbench to achieve a height that will make the floor represent the bottom of the gas tank when the tool is set on top of the lumber stack. Now set your actual sending unit on that same stack of lumber and compare position of bottom of float with the floor (fake float on your tool should be resting on floor). Adjust your sending unit float arm till float rests on floor with arm in the empty position.
Now take your clamp off "empty" and clamp measuring stick to "full" position on your tool. Set tool back on lumber and use a ruler to measure from floor to TOP of fake float loop. Compare position of sending unit float to that same height when float arm is lifted up to the "full" stop point on the sending unit.
If it matches, you are done with float arm adjustment.
If sending unit float is higher than fake float, measure the DIFFERENCE between height of fake float and sending unit float. Divide that distance by one half and bend the sending unit float arm DOWN. This will give you a perfect reading in the middle of the guage when the gas tank is half full.
Do the opposite if the sending unit float is lower than the fake float.
NOW you know that your sending unit float is adjusted properly.
 
If you know that your sending unit float is adjusted properly, now you can test guage.
To do this adjustment, fuel guage must be removed from the dash. Remove the rear mounting plate of the guage to gain access to the two adjustment holes in the back of the guage. A very small straight blade screwdriver is needed to make adjustments. Be very carefull not to allow screwdriver to slip as it could result in damaging guage.
If your gauges are powered from a circuit connected to the coil circuit of the ignition switch, I would remove the power wire connection from the guage temporarily and connect a temporary jumper wire from battery terminal so that all other circuits in the car are dead.
Connect jumper wires with alligator clips from guage wires under dash out to the guage terminals. Use a very fine stranded wire with alligator clips to ground the guage case to the firewall ground.
In order to avoid the need of emptying and refilling the gas tank, you should be able to simply leave the sending unit in-installed and just connect jumper wires from the car wiring to the sending unit. Make sure your connection to the sending unit terminal is not touching the unit case. Run a jumper wire with alligator clips from the sending unit case to good body ground. (if you already have a ground wire for the sending unit, just clip on to it). If not I strongly suggest adding a ground wire for it.

Connect your power alligator clip to the guage terminal and see where the guage reads while moving the float arm to the "full", "half full" and "empty" positions.
If the guage does not read where it should. You need to make adjustments at the back. If corrections cannot be achieved by adjusting the little starwheels in the back, I think you should attempt to find a compatible guage.

PS. when I did this operation, I had the guage sitting upright on top of a short stepladder with some heavy objects holding the wires down to the top of the stepladder so the guage would not move BEFORE attempting to read the guage. If the guage is not sitting perfectly upright and level, the needle may read falsely.
 
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Not to argue or make light of how you did it but holy cow, that seems to be a lot of unnecessary work. Besides, to make my gauge work correctly with the sending units available today my float arm would have to be twice as long as the tank is wide. Why not just remove the sender and measure the depth of the tank through the sender hole to the bottom. Place the top of the sender under a piece of wood as long (or longer) than the float arm and secure with a screw from the bottom of the sender mounting plate into the wood. Lay the sender on its side and measuring down from the wood make a mark corresponding to the tank depth. Make half and quarter measurement marks. Now attach sender to gauge with jumpers. I'm not much on bending/tweaking 60 year old anythings, one wrong or too many tweaks and poof!, nothing left to work with.

Sorry, but my schedule and the weather hasn't left me much of a chance to move forward on this. I'm responsible for a lot of first responder vehicles and my best made plans don't always pan out. I've got everything I need except time.
 
I just thought I'd update the drama with my 55 fuel gauge. I replaced my sender with a universal sender from Carpenters that lists as being for 32-55 Fords 6 or 12 volt. Absolutely no change. I sent it to a auto electrician who found that the wires on the fuel and temperature gauges were swapped around. Connected up properly and then found the temperature gauge worked though was inaccurate but the fuel gauge remained pegged on empty. It was a 90-18 ohm sender but the needle never moved even whilst driving. I had an original old sender, put it in the tank and voila!, the fuel gauge works. Seems when I connected the gauges I had a seniors moment and reversed the two sender wire in the harness plug. Certainly explained why the fuel gauge was slow to register and just kept climbing the longer I drove and the temperature just bounced around where it felt like. I replaced the temperature gauge sender with the correct part and it works correctly as well.
I just thought it was the right thing to tell the outcome. Thanks for all the comments. I've accepted now I'm too old to get under dashboards anymore.
 
I just thought I'd update the drama with my 55 fuel gauge. I replaced my sender with a universal sender from Carpenters that lists as being for 32-55 Fords 6 or 12 volt. Absolutely no change. I sent it to a auto electrician who found that the wires on the fuel and temperature gauges were swapped around. Connected up properly and then found the temperature gauge worked though was inaccurate but the fuel gauge remained pegged on empty. It was a 90-18 ohm sender but the needle never moved even whilst driving. I had an original old sender, put it in the tank and voila!, the fuel gauge works. Seems when I connected the gauges I had a seniors moment and reversed the two sender wire in the harness plug. Certainly explained why the fuel gauge was slow to register and just kept climbing the longer I drove and the temperature just bounced around where it felt like. I replaced the temperature gauge sender with the correct part and it works correctly as well.
I just thought it was the right thing to tell the outcome. Thanks for all the comments. I've accepted now I'm too old to get under dashboards anymore.
 
rick55 said:
I've accepted now I'm too old to get under dashboards anymore.
Click to expand...

Maybe so, but you're still goin to do it anyway, cause whenever somethin goes wrong, you can't stand it till it's fixed, so you'll tackle it until you are satisfied. It's in your blood. :D
 
I bought a Carpenter sender for my '40 Ford Sedan. Mine is 6v and it too works very slowly, but when tank is full it goes past the full mark a little bit. It just takes some getting used to, but at least it works. The sender in my '57 F100 and the gauge work backwards. When full it shows empty. When empty it shows full !
 
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