Fuel Sender Replacement

[1950 Special Deluxe]

Trying to confirm fuel sender for my car.

1950 Dodge Special Deluxe (Cdn. version of Plymouth Special Deluxe) 6 volt positive ground. Parts manual lists it as 1240864. It is a single terminal sender. I will attach pictures. Is number P232 from Roberts the correct replacement? It is listed as for 49 - 57 cars. Andy Bernbaum's P-193 is listed as for 49 - 55 Dodges. Gauge seems to work, slams to full when I ground the wire. I could not get any resistance when I had the sender removed and was moving the float so I presume the sender is faulty.

[P-12 Tommy]

When you had the sender out, did you ground it?

Tom

[55 Fargo]

Trying to confirm fuel sender for my car.

1950 Dodge Special Deluxe (Cdn. version of Plymouth Special Deluxe) 6 volt positive ground. Parts manual lists it as 1240864. It is a single terminal sender. I will attach pictures. Is number P232 from Roberts the correct replacement? It is listed as for 49 - 57 cars. Andy Bernbaum's P-193 is listed as for 49 - 55 Dodges. Gauge seems to work, slams to full when I ground the wire. I could not get any resistance when I had the sender removed and was moving the float so I presume the sender is faulty.

Can you use a universal single terminal fuel sender unit, very inexpensive.

As long as it has the correct ohm range.

1 wire fuel senders are much easier to deal with and to locate, you may not have to pay the extra money froma place like Roberts or Bernbaums, when a universal 1 wire sender may work........Fred ps yes your's is a 1 wire sender, as they were after 1949

[1950 Special Deluxe]

I used my meter and went from the terminal and used various spots on the shell itself. I made sure I had a good connection and then moved the float up and down and no reading.

When you had the sender out, did you ground it?

Tom

[1950 Special Deluxe]

I had bought an universal sender and that was my initial idea. But, the mounting flange on the universal one was a 5 hole pattern and on the original it is held in by the locking plate. I thought about trying to retro the 2 into making 1, but figured I would end up with nothing and possibly bugger up my tank in the process.

Can you use a universal single terminal fuel sender unit, very inexpensive.

As long as it has the correct ohm range.

1 wire fuel senders are much easier to deal with and to locate, you may not have to pay the extra money froma place like Roberts or Bernbaums, when a universal 1 wire sender may work........Fred ps yes your's is a 1 wire sender, as they were after 1949

[55 Fargo]

I had bought an universal sender and that was my initial idea. But, the mounting flange on the universal one was a 5 hole pattern and on the original it is held in by the locking plate. I thought about trying to retro the 2 into making 1, but figured I would end up with nothing and possibly bugger up my tank in the process.

Interesting, as the 46-48 Mopar tanks were a 5 hole pattern sender, guess Mopar was trying progress for 49.

Too bad cuz JC Whitney has 1 wire senders for Mopars, witha Ohm resistance range of 78-10 ohms........Fred

[TodFitch]

I had bought an universal sender and that was my initial idea. But, the mounting flange on the universal one was a 5 hole pattern and on the original it is held in by the locking plate. I thought about trying to retro the 2 into making 1, but figured I would end up with nothing and possibly bugger up my tank in the process.

See: http://www.ply33.com/Repair/fuelsender.html

[P-12 Tommy]

1 meter lead to the terminal screw, 1 meter lead to the body of the sender:) Move the arm, watch the meter.There is nothing to ground.

I thought if you check it with 6 volts from the battery, you have to ground it to make it work.

Tom

[aero3113]

Here is what I did with a single wire unit from JC Whitney.

[55 Fargo]

Keith, that looks slick,you used the cap from your oem sender correct? Is this sender from JC Whitney, the Mopar Universal type, they are only $22.99, a lot better than the $85.00 I paid fro my 2 wire deal from Roberts....

[aero3113]

Thanks Fred, I got the idea from this site http://www.ply33.com/Repair/fuelsender.html but attached the top plate a little different. Works great .

[P-12 Tommy]

I believe he was doing a ohms reading of the single wire sending unit by moving the float arm after it was removed from the tank:)

That makes perfect sense.

Tom

[1950 Special Deluxe]

Picked up a sender from my friend's donor car today. It does not function either, but it is a good candidate for adding a new universal sender to it. I can get a universal 1 wire sender with the appropriate ohm ratings for just over $20. Will try to do this week and post pictures and updates. Thanks to everyone for the info.

[BobT-47P15]

It just makes me wonder......every time I see one of these one wire

senders with an exposed wire end which will be residing inside a gas

tank. It seems like it would be dangerous due to a possible spark, but

I guess it isn't.

[TodFitch]

It just makes me wonder......every time I see one of these one wire

senders with an exposed wire end which will be residing inside a gas

tank. It seems like it would be dangerous due to a possible spark, but

I guess it isn't.

The current and voltage is quite low so a spark is unlikely even given a poor design. On the units I've looked at the sweep arm contact touches more than one fixed contact at a time (make before break) so there should be no possibility of a spark at all. And even if there is, you need the correct fuel/air mixture for an explosion and, with the possible exception of an empty tank, the mixture in the tank is too rich.

[1950 Special Deluxe]

Thanks Tod

You answered my question before I could ask it.

[BobT-47P15]

O K

[1950 Special Deluxe]

I could not source a universal sender with the proper ohms ratings locally. Found a 30 - 240 ohm sender and proceeded to alter it to fit. Then I added a couple of 220 ohm resistors in parallel across the single terminal and a ground terminal that I added. This brought it down to about 77 ohms when empty, I adjusted the float arm (not shown in my pictures) so that it travels further up when full to lessen the resistance to about 40 ohms when full. Right now from looking in the sender hole of the tank it looks about just over 1/2 and that is what the gauge reads. I am more concerned about the bottom half of the tank as opposed to the top half,

Thanks

[TodFitch]

I could not source a universal sender with the proper ohms ratings locally. Found a 30 - 240 ohm sender and proceeded to alter it to fit. Then I added a couple of 220 ohm resistors in parallel across the single terminal and a ground terminal that I added. This brought it down to about 77 ohms when empty, I adjusted the float arm (not shown in my pictures) so that it travels further up when full to lessen the resistance to about 40 ohms when full. Right now from looking in the sender hole of the tank it looks about just over 1/2 and that is what the gauge reads. I am more concerned about the bottom half of the tank as opposed to the top half,

Thanks

Looks like a cork float on that.... Is that the float that came with the universal sender? How will the shellac on that handle the ethanol in modern gas?

[1950 Special Deluxe]

I re-used the float off of the old donor sender.

There is a plastic one with the universal.

Should I change to the plastic one?

[Don Coatney]

Tod;

Once again (as expected) you made me search shellac origins. Below is a link to part of my findings but also the most interesting of my findings.

http://antiquerestorers.com/Articles/jeff/shellac.htm

I did not know shellac was an insect product until I read this.

[TodFitch]

Tod;

Once again (as expected) you made me search shellac origins. Below is a link to part of my findings but also the most interesting of my findings.

http://antiquerestorers.com/Articles/jeff/shellac.htm

I did not know shellac was an insect product until I read this.

Thanks for the search. It looks like shellac dissolves in all types of alcohol. And while that is good if you want a liquid to apply to a surface, it is not good for the long term:

Once the dry flakes are dissolved in ethanol, a chemical process known as esterification begins. What happens is that the alcohol starts to chemically modify the hard shellac resins and ultimately turns them into a sticky gum which doesn't dry.

Sounds like something that I would not want in a gas tank that will be filled with a liquid containing even a little ethanol.

[1950 Special Deluxe]

Tomorrow after work, I will remove the sender and put the plastic float on. I am in this deep, I might as well complete the task.

Thanks for the help.

[Chachos 49]

This is my sending unit from gas tank. It’s a ‘49 Plymouth. It’s set up for 1wire. Does tank ground itself and wire goes to ignition?

[Sniper]

The tank grounds itself and the wire goes to the fuel gauge