Back in 2015, the original cork sender float was fuel soaked and wouldn't float. I replaced it with one I made from thin brass sheet. It has done fairly well, but on my last trip out for fuel, the gauge was reading empty, despite a full tank. A quick test with a jumper cable showed the gauge was working, so I suspected either a bad earth ( a common problem ) or a sunk float. I had a feeling that the ethanol in the fuel may have attacked the brass or solder. The jumper wire was used to create a separate earth for the sender, but the gauge didn't move. Pulling the sender out showed my initial gut feeling was correct and I heard fuel sloshing around inside the float.

Back in the workshop, I found a small split in the rolled brass body of the float. After draining the float, the split was soldered and then a thin brass patch was soldered over the top of the repair. I lowered the float into the tank filler neck and felt that it wanted to float and saw no bubbles coming from it. It was then refitted and the power turned on to check the gauge. It works, but I need to bend the sender arm as it isn't reading accurately ( it didn't before! ). I'll wait to see if it stays floating first, before making any adjustments.