The diesel fuel tank on my boat is in the center of my boat just forward of
the mast and the engines are in the back so the fuel lines pass through the
cabin. There are no fuel leaks, the lines are made from a gray rubber and
smell strongly of the diesel fuel. The boat is 6 years old. The runs are
about 45 feet and they do a fair amount of twists and turns. I am thinking
about replacing them with soft metal tubing, maybe copper (Home Depot water
tubing) or 3003-0 aluminum (aircraft grade fuel line). Of course I will
leave a short flexible part near the engine for vibration. Does anyone have
any advice about these or other metals for diesel fuel lines or other fuel
line material that will not end up smelling in a few years?

Thanks in advance,
Mark