No Fuel Sending Unit?? Help!

[MPKehoe09]

I recently purchased a 1998 Aquasport 175 Osprey. The previous owner mentioned that the existing fuel gauge didn't work, so I figured I just needed a new sending unit, and problem solved.

After closer inspection, I'm a bit confused...It looks like the sending unit was removed, and some sort of "cap" with a clear lens was installed (epoxied??) in place. Right near this cap, are three wires that were cut (Black, Green, and Pink). Green is my ground that traces back to the fuel filler inlet. The black grounds to the battery, and the pink traced back to my fuel gauge.

This leads me to believe at one point there was a sending unit, and something was retrofitted. Any idea why this would be done?

I've been using a portable above deck tank, but would love to get the internal tank in use.
However, the lack of the sending unit and retro-fitted cap concerns me.

Anyone have any ideas?

 

[Grub54891]

That green wire is the bonding wire, it must be hooked up, to prevent corrosion, and spark protection at the filler neck. The other 2 wires actually are for the gauge, Some gauges have a clear lens, that indicates fuel level right on the tank, but also run the dash gauge. I'm guessing the sender went south, and they cut the wires. Was the po using the internal tank? And if not, it may have a leak and may need to be repaired first.