It depends on the type of engine. My 272 has a Westerbeke 10-2. It has a self bleed system. I also use a TEMPO fuel tank/pump. I fish the long tube down the Diesel Filler Cap making sure that it reaches the bottom of the tank. Then pump, pump, pump. Very easy. I then pour the diesel fuel from the 272 tank into my diesel car. I also have a Groco fuel filter, and two filters on the engine, All renewed every year. If your tank is like mine, you can't remove in from its location.