Diesel fuel tank sending units/gauges not working

[Four Suns]

This problem has been getting worse over the last year. My fuel gauges on both the port and starboard tanks are getting flakey. They are part of a gauge that has multiple embedded gauges in it (oil, voltage, fuel, temp). What happens is they will sometimes read correctly and then drop down to less than what is really in the tank. The port gauge pretty much reads "E" all the time now. I keep track of my fuel via the fuel burn on the digital cummins display but this is really annoying. The other embedded gauges work fine. Both sides (different gauges) are exhibiting the same problem but port side is worse.

Suggestions? Sticky/shot fuel sending unit?

 

[never monday]

floats on the sending units are saturated and not floating well.

 

[fwebster]

I agree with Pat...........you can test the sender by removing the wire from the center terminal on the sender and touching it to the tank ground....the black wire also on top of the tank. The fuel gauge should peg to full.

This will give you wife something constructive to do while you crawl around messing with the wires on top of the tank!