1949 Plymouth fuel sending unit

[normffff]

I am trying to get my fuel gauge to work...took the sending unit out of the tank...it looks completely different from anything I see online...it is a cylinder approx 2 inch diameter x 6 inches long... everything else i see is a skinny little bent rod with a float...any comments or suggestions...thanks

[Plymouthy Adams]

photo would be needed.....that does not sound anything near to stock and could well be a universal style as commonly found in the marine division.

[normffff]

thank you plymouthy...apparently its a "floatless" sending unit...definitely not stock...only one wire from it...is it safe to add a ground wire?

[Plymouthy Adams]

I will offer no advice toward connecting until I personally could identify the unit, its impedance and swing, as some are opposite of others.    Just this last Sunday I repaired a vehicle that was comingled with parts and totally inoperative.  Not only were the components not compatible, the man had added a CVR when not needed.  The sender not conmpatible for the gauge in use and on top of that, nuts on gauge were loose, the gauge was not connected good to the cluster, more loose screws and offering ground issues.  The wire to the tank I can confirm was good....!!!   While the cars did look identical from late 40's through 71, there were a few changes along the way....and yes either gauge would bolt to either cluster...and you can easily remove the face and switch if needed...little drilling of rivets, and many gauges are drilled for repairs for the last 30 odd years or better.  However, you first needed to know what would work with what and this was the main issue at hand.  Not knowing the differences.  I repaired two of these guages for bad connections internally and broken wires on the coils as I may have needed one for this build, I did not, just needed a bit of tender tweaking.

Edited April 5 by Plymouthy Adams

[normffff]

thank you for your comments, and i understand why you cant really offer advice... yes there could be a myriad of reasons the fuel gauge doesnt work...just thot I'd start with the sending unit, and work my way thru all the electrical connections...thanks

[Plymouthy Adams]

understand but as stated...you do not know what sender you have and without a picture we could never guess 

[Los_Control]

Makes me wonder if possibly you have a aftermarket tank installed ... and a sending unit sold with that specific tank.

If possible you knew where the tank came from ... might help identify the sending unit. .... then identify proper wiring procedure.

 

Just a heads up ..... I recently wired my new tank/sending unit to the original gauge ...... on my 49 Dodge truck ... sending unit had 2 wires, one for power and one for ground.

Exactly what my original gauge needed. .... Just a heads up, seems 2 gallons of gas is not enough to activate my gauge .... needs lots of gas, 4 gallons to get it off of E

 

With all that said, if you have a replacement tank and a 1 wire sending unit .... you might need to purchase a aftermarket gauge to work with what you have.

More info is needed.

[Harley PHD]

You should be able to unhook the wire from the sending unit and the gauge should read empty, and ground the wire and the gauge should read full.  If not, something is wrong between the sending unit wire and the gauge.

[normffff]

Thank you all of you... Yes this has got to be a different tank than original, and because of that, has a different sending unit.

I've also found some breaks in the wiring under the dash, I'll deal with that and see how it goes.

And I'll add a ground wire at the sender.

Thanks again