At my wits end, good ole fuel gauge troubles

[FlamesAreWicked]

The short and skinny of it. 1968 Dodge Dart

Sending unit is giving me a reading of 66 ohms. It’s a new sending unit. There’s about 4-5 gal in the tank. This reading was using my multi meter on the stud of the sending unit and the metal line that comes from upstream on the car. I applied ground briefly to the plug that goes on the sending unit stud using a power probe and the gauge in the cluster does rise as it should. With everything connected as it should, I added a supplemental ground with alligator leads from the metal line coming out of the sending unit to the metal line from the car. My gauge doesn’t budge off empty

I have a new solid state limiter in the cluster along with new circuit boards. I’m getting 5v at the plug when checking with my power probe.

At this point, only thing I can think of is maybe the plug isn’t getting a good connection to the stud. When I checked it with the power probe, since the end is pointy it’s touching at the very deepest point of the plug where the stud isn’t. I dunno, I’m just spit balling at this point.

The brand of sending unit is The Right Stuff and has a range of 6-78 ohms. Accuracy isn’t the goal.. but to have some function going on would be great.

 

[Dana67Dart]

With 4-5 gallons in the tank I would not expect much more than that from any aftermarket sender.

The curve (or lack there of) on these senders is full for 3-4 gallons, 1/2 for about 8 gallons then empty for the remaining 3-4 gallons.

Look at the graph in post 4.

Product Review: A100 Fuel Sender For 67 Dart

 

[FlamesAreWicked]

With 4-5 gallons in the tank I would not expect much more than that from any aftermarket sender.

The curve (or lack there of) on these senders is full for 3-4 gallons, 1/2 for about 8 gallons then empty for the remaining 3-4 gallons.

Look at the graph in post 4.

Product Review: A100 Fuel Sender For 67 Dart

I did see the the graph in another thread trying to read up on tips that I may have missed. Guess I can dump another 5 in and see what happens. When I replaced the tank and sending unit, all I had was a 5 gal can to pour in and I did take one little trip in it to check another thing I was working on.

 

[MadScientistMat]

Gauges read pretty close to empty at 66 ohms. I did a video of testing two '66 gauges with a set of resistors:

 

[FlamesAreWicked]

I poured some more fuel in. My resistance reading on the sending unit stud is a little bit over 50 ohms. Gauge is still showing empty.. passed empty even.