trying to find out why tank is not venting properly - and in the course of things - don;t know which hose is which here. Labels gone. The boat has a diesel generator and an auxiliary diesel tank that can pump fuel into the main tank. I can see labels for the genset - feed and return but without tracing does anyone know what the other ones are ? I was thinking the one with a valve is probably the main engine feed and that is a shutoff valve ? Anyone have an idea which is which ? If one is the vent I was going to disconnect it and blow air through and out the mushroom valve. Thanks all