When I bought #1331 in 2005 the tank was removed, taken to a radiator shop, boiled out and pressure tested. I replaced all the inlet and outlet plumbing, including a new fuel shut-off valve. The outside of the tank was polished and the tank reinstalled.There seem to be a lot of different e-pinions on copper/Diesel. Because the boat was switched to Diesel circa 1983, and showed no signs of trouble when I bought her in 2005, I was comfortable leaving the tank in use. In case of a leak that sent fuel into the bilge, causing the bilge pump to happily pump it all overboard, I installed a Water Witch pump switch that cannot be activated by fuel. Better to have a bilge full of Diesel oil than a large slick in the marina!I like the location of the tank as it's high up in the boat, very visible for inspection, and away from exposure to salt water. It also gravity feeds fuel to the engine, which is a nice feature if the fuel pump takes a vacation. If I were to increase tankage I think I'd place something under the aft end of the cockpit floor, but at the consumption rate of about 1.5 liters per hour a 33 liter tank lasts a long time. For extended cruising I generally carried a couple of 2.5 gallon fuel cans, a more convenient size/weight to transport and stow than the 5 gallon size. I seldom needed to use them, but they were easy to stow and to transport on my bike.Peterwww.mostlyaboutboats.ca