1955 ford ranch wagon Fuel sender question.

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poolplayer1

Senior Member
I was driving my 55 yesterday and ran out of gas.The gauge was reading 1/2 tank of fuel. I had purchased a generic fuel sending unit awhile back.The part # was FAA-9275-B.It was a little off but not that bad.The vendor told me at the time that it would work on eighter 6 or 12v. At the same time that I replaced the sender,I took out the 6v fuel gauge and put in a 12v from a 1957 ford station wagon. Now I don't know if the sender went bad on me or did the gauge mess up. I know that expecting a true reading on this after market parts is not possible.I know that but being off half a tank is too much.I know that there has been quite a bit of discussion on this topic but I wanted to ask again.
For you that have replaced this parts before,is there any reliable sending unit for this wagon? Is there a parts house that might sell a sending unit together with the fuel gauge that both can work together pretty reasonable?
I wonder if I should try to find a 6 volt gauge (My oem was bad)and 6v sending unit and maybe use a voltage reducer to convert from 12 volt to 6 volt.If I can't find anything I guess the only thing I can do is have a full tank every time I go for a drive.
Let me know if you guys have info on this 2 parts.
Thank You.
 
Generic sending units won't play well with original Ford gauges from the late 50s and earlier. The original gauges work on a different principle from more modern gauges. Look up King-Seeley gauges and you'll see what I mean.

Your '57 fuel gauge is not 12v, it's 6v. Ford used 12v gauges for the '56 model year only when they went to 12v electrical systems. Beginning with the '57 models they went back to 6v gauges and used an instrument cluster voltage regulator for all gauges except the ammeter. If you weren't using a cluster regulator I suspect this is why your fuel gauge went bad.

There are aftermarket fuel sender and gauge sets available but will likely require you to mount the gauge under the dash since they usually won't fit in the cluster. If you want to keep it stock some of the usual suspect suppliers have the King-Seeley senders. I see used original gauges on eBay pretty often.
 
The oem '55, '56, '57 gauges and senders are each a one-year-only internal design.
The best chance you've got of having the Fuel level read correctly is to have a year matched gauge & sender pair.
Either oem or a reproduction pair, but not a mix.

The original '55 King-Seely type gauge & sender work on current flow and heat generated thru an on/off switched circuit, not variable resistance or voltage.
If you have a matched pair of those in good working condition they usually aren't voltage or polarity sensitive.

"You do not need to change any switches or gauges. The fuel and temp gauges will work on 6 or 12 V and are not polarity sensitive."
https://www.ctci.org/battery-for-6v-to-12v-conversion/
 

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The 57 gauge is a six volt gauge. They used a voltage drop to get to 6 volts. The voltage drops are readily available.
 
A '57 fuel gauge is designed to be paired with a sender that has a variable resistor inside.
 

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So, which is the best way to go at this problem.Do I order another 57 gauge and install a voltage regulator inline or maybe use a 10 ohm 1ow wirewound resistor to drop the voltage to 6v or try to find a sending unit that has the variable resistor built in that will work with the 57 gauge. What about if i try to find a fuel gauge and sending unit for a 56 ford.Do you think that those 2 would work ok? Is the 56 a 6V or a 12V.
Do you have any suggestions where I can find a place that will have this 2 parts?
I don't mind the reading being a little off but half a tank is too much.
I noticed that the 55 t-bird uses a gauge cluster that looks the same as mine.Maybe I can try getting those 2 parts from a T-bird place. Let me know what you guys think about this and as always,thanks for all your help.
 
I would use either a '55 gauge or another '57 gauge and a cluster voltage regulator, not a wire wound voltage drop. The wire wound ones have to heat up before they start resisting enough to drop the voltage. The '56 are 12v but can be hard to find since they were 1 year only.

The cluster voltage regulator looks like these and can be had from most parts stores. Get one that has the spade terminals, not the snap terminals.

https://www.google.com/search?q=for...WluFkKHUhkDeQQ_AUoA3oECBUQBQ&biw=1920&bih=937

The T-bird suppliers may be a good bet but keep in mind that the T-bird tank depth may be substantially different from the wagon tank. I would look for a sender that has an adjustable length float arm.
 
Thanks Dobie for your great help.I really apreciate your knowledge on this subject.
By the way,I had said that the fuel gauge that I had installed in the wagon was from a 57 ford but i was wrong.I found the receipt of when I bought it,I purchased the gauge from Macs Auto parts and it was from a 56 ford truck. I guess I messed up and thought it was for a wagon.But it is for a 56 and it is 12 volts.I looked at the picture of the gauge on macs website and you can see where it says 12 volts right on the gauge itself.Eventhough its a 12v,which my car is,the gauge is probably not compatible to the sending unit.The sender that I put in the tank was from macs too and it was for a 55 ford wagon.It stated that it could be used on eighter a 6v or a 12v system.Now I am really confused.
 
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OK, before you order any more parts you need to suss out the problem by testing. This is from the '53 passenger car shop manual but the tests still apply because the gauges operate the same as your '55.

FUEL GAUGE INOPERATIVE

Turn the ignition on and observe the fuel gauge. Follow (a) or (b), whichever applies.

(a) GAUGE READS OVER THE FULL MARK. If the pointer goes beyond the scale on the FULL side a wire in the circuit is grounded. Repair or replace the wire.

(b) GAUGE DOES NOT READ PROPERLY. If the gauge does not indicate properly or fails to indicate, momentarily short the terminal wire to ground with a jumper wire until the pointer reaches the highest reading on the gauge, then immediately remover the jumper wire. Follow (1) or (2), whichever applies.

(1) GAUGE READS FULL. If the pointer reaches the maximum travel on the scale when the wire is grounded either the sending unit or the wire connecting the sending unit and gauge is faulty. Turn the ignition off and ground the sending unit terminal. Turn the ignition on momentarily. If the gauge begins to indicate the sending unit is at fault. If the gauge does not indicate, the connecting wire is broken.

(2) GAUGE FAILS TO INDICATE. If the gauge does not indicate when the wire is grounded replace the gauge.
 
poolplayer1 said:
. . . I purchased the gauge from Macs Auto parts and it was from a 56 ford truck. I guess I messed up and thought it was for a wagon.But it is for a 56 and it is 12 volts.I looked at the picture of the gauge on macs website and you can see where it says 12 volts right on the gauge itself. Eventhough its a 12v,which my car is,the gauge is probably not compatible to the sending unit.The sender that I put in the tank was from macs too and it was for a 55 ford wagon.It stated that it could be used on eighter a 6v or a 12v system. Now I am really confused.
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Part of the problem could be that you've got parts designed for two different years. The electrical specs of the internal parts of the (original) gauges & senders changed from '55 to '56, and again from '56 to '57.
A replacement style gauge for a '55 may (should) be more compatible with the replacement style '55 sender you have.
IF the manufacturer is still making them the same way, and Mac's is using the same supplier.
.
 
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Thanks guys for your help. I will do some troubleshooting on both the gauge and the sender and see which one is the culprit.
 
I just put new aftermarket gauges in my 60 Ranchero and could not use the aftermarket sender that came with the gauges due to the side mount of the stock sender in the tank.
The sender worked the gauge but it would read full when empty and vice versa. I was told of a device sold by Tanks, Inc. That corrects any operable sender with any operable gauge. It is called Meter Match. Just ordered it and I will know in a week or two if it fixes my problem.
Rich
 
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