Finally, check the sender's output over the full range, making sure it produces a smooth continuous signal from ~16~160 Ohms. If not, replace it.
Broncos & front tanks use a hollow brass float as shown. (F-series rear tanks use a solid foam float.) If liquid can be heard splashing inside, or if the float remains wet with fuel, it should be replaced. But with EXTREME care, it can be emptied, polished, and the leaks soldered shut with a common electronics soldering iron & rosin-core solder.
To test it for leaks, put it in a freezer for ~5min, then quickly submerge it in HOT water. Bubbles will emanate from the main leaks. Repair & repeat testing until all leaks have been stopped, and the float is empty.
New replacements are inexpensive & common, but hollow floats are inherently UNreliable.
Aftermarket hollow plastic floats are also available, but a foam float is vastly superior.
