Sending unit

[Data Plate]

I replaced the gas tank and sending unit in my 69 charger and the gas gauge still does work This is what I did before installing the sender I tested it out of the car I put the power wire on it and grounded it I turned the key on and my friend lifted the float slowly up and down the gauge moved up and down in a jumpy way not smooth then I put it in and nothing the gauge didn’t move at all so I bought another sending unit and tried it and it did bathe same thing the ground is good any ideas on what it is

 

[Beekeeper]

The aftermarket senders are notorious for this exact issue. How much fuel do you have in the tank? The aftermarket senders are non linear in the way the windings are wrapped the originals were a linear design so the new senders will never work as well as the originals. The best thing to do if you have your original is send it out and have it rebuilt.

 

[PurpleBeeper]

New senders are junk...but, I would redo your tests. Ground the sender wire and see if the gas gage pegs on full (key on of course). If yes, then re-check your ground..fuel line to frame, ground strap to frame, pump to frame. Often that strap is the issue. If you have an aluminum fuel line or something, you may need to run an extra ground wire. "Somewhere" I saw an electronic part you can put inline with the sending wire and "dial in" the gage readings. OR, rebuild the stock sender

 

[66Satellite47]

Ground strap on the sender to fuel line may be the issue.

 

[Jc cooper]

Yep , if all test ck out and probably grounded and no success with repop sender , tanks inc , has a little device that works really well and not to very expensive!

 

[Data Plate]

Ok thanks for all the help when tested it went to full worked fine but once in the car nothing I thought it was a ground issue also but have it grounded well I do have the original sender from the car who rebuilds them

 

[Data Plate]

I see a place called tri Starr that rebuilds them in ny what’s the name of the device that goes inline

 

[Jc cooper]

Thinks it’s called meter mender , but tanks inc ,com makes them ! They work good, easy install and set up !

 

[Jc cooper]

Sorry correct name , Meter Match at Tanks inc .com I used this to solve bs fuel gauge repop sender !

 

[Data Plate]

Sorry co name , Meter Match at Tanks inc .com I used this to solve bs fuel gauge repop sender !

 

[Data Plate]

I saw it online the meter match I’m also gonna call the place that rebuilds the sending unit

 

[khryslerkid]

Do you have the ground strap installed that bridges the hose at the sending unit?

I also like the Spectra units. They're made here in the US.

 

[Data Plate]

I checked the power wire today and it’s not steady power it goes on and of pulsates should it do that or be steady power to it

 

[dadsbee]

Let's get beyond the fact that the wire AT the sender is not a power wire, it is the input wire for a variable ground to the gauge. Yes your dash gauges work on a pulsed 5 volts. If you are reading that pulsed voltage at the tank end of the sender wire then you know it's attached to the gauge at least. Ground the wire directly to a good ground while someone watches the fuel gauge. Does it go full scale??.. DO NOT hold it there, proper way is to have a 10 ohm resistor between wire and ground and it will (should) show a full tank. Put the sender wire back on the sending unit. If there is fuel in the tank and the gauge now shows nothing it's one of three things. You don't have a good ground to the sending unit, or the fuel level float has sunk, or the rheostat isn't making contact with the float arm contact.

 

[Data Plate]

Ok thanks for the help I’ll give that a try

 

[Data Plate]

I ran the ground wire with the 10 ohm resistor and when I turned the key on the jumped to like 1/4 then 1/2 then 3/4 and stopped at 3/4 it didn’t go up fast but in increments would that indicate a bad gauge ?

 

[dadsbee]

At least the gauge is working, so you know it's a tank ground issue or float/rheostat issue. The gauges work on a 5 volt pulse from the voltage regulator, so that is how the gauges move to some degree. The gauge is adjustable/calibrate though holes in the back as you can see in this picture while I had mine apart for restoration. It is of course possible you have some wire or connector corrosion from the tank to the gauge circuit board that could account for you being 1/4 tank off full, but doubtful considering it's working that well.

 

[hunt2elk]

The aftermarket senders are non linear in the way the windings are wrapped the originals were a linear design so the new senders will never work as well as the originals.

You have that backwards. The original senders were non linear and all the new reproductions are linear.

 

[Beekeeper]

You have that backwards. The original senders were non linear and all the new reproductions are linear.

I get confused easily

 

[hunt2elk]

I get confused easily

Lol, I do too.