none of the “new “ senders sold by all the vendors are calibrated correctly for our mopars . I have 5-6 in various cars ( little choice if old one is toast ) they do not track right . All the same chinese junk . Not one works right . Not just several 300 , —a Dart and two dodge trucks too . The rate of change of ohms or float travel ( arm geometry ) or both is wrong . If you look at the stock resistor winding , the resistor is non linear it changes width as wound on the form in the tank sensor in an engineered way to drive the probably non linear gauge to track the gas level . That non linearity probably varies with tank shape. Slanted bottom for instance .
= save the old one ...... job 1
you cannot fix that tracking problem with resistors either .
Two other possibilities , figure out E on gage vs arm out of tank and bend arm E so E end is near correct in tank (what you really care about ) , when float is down ,easiest when the tank is out of car , —- F accuracy really does not matter . Resistors will impact F end only , essentially . If you try to correct E with resistor to make it read lower gauge will not go full travel , as it can no longer get to 10 ohms. (F)
I have tried to put yellow stickies in each car ( sad ) telling me the story . You forget .
When Dart reads E it still takes 11 gallons . So you drive on E and watch odometer , leading to running out . It Goes from E to F in just last 8 gallons . Others not as bad but you get it . yet sender is correct 10-90 ohms approx .
The brass float tank on an old one can be fixed by adapting ford parts . Was 18$ for two new Ford brass floats a while back . maybe you can save the old resistor part by careful cleaning rust out with Q tip and wooden toothpick inside the little box . Do NOT bend little arm to “make better contact “ it will rip up the resistor wire in a month . been there . resistor wire is very fragile why no metal tools .
If winding wire is already ripped or loose it is junk .
Last , while chasing this , Tanks Inc sells a really nice universal mechanically adjustable sensor , available
with mopar 10-90 ohm range , designed for their tanks , but best part is it has a spectacular instruction exactly how to measure to set it up , the float travel , arm length , centering the pivot in the tank depth etc . Those parts come with it.
This looks to me to be rather easily adaptable to our stock inlet fitting and the stock resistor support or mount arm . I have not had the time — although I bought one .
Maybe someone else does it — with a tank out of car . Connect that tank on bench to the car with two jumper wires . Document it .
The other post about ground is very true . You can solder a wire , 14 ga stranded building wire to the outlet pipe below outlet hose . clean thoroughly till shiny . Run to frame . Mostly though , bad ground shows as an E reading there all the time or comes and goes , not an error in reading .
Hope this helps . Frustrating thing .
John g
ps don’t mess with dash gauge over this . goes nowhere but trouble .
PPS , new G tanks are listed —but not F ! It turns out the difference is length of filler pipe . It works ok
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