It’s been three or four years since I last took a fuel senders apart for the 911. These are for 914 tanks but they are the exact same unit sans the part number. They get corroded inside and especially along the stem that guides the float up and down. The corrosion looks like barnacles on a pier pylon in the Pacific. It picks and sands off easily enough but leaves the rod devoid of a protective coat from the plating process. I worry they might corrode faster now so I dress them with a little oil as they wait to rise to the occasion once again.