Generally the top of the diesel fuel tank
is accessible somehow as the vent, fill and return hoses all need to be serviced. On my built-in fiberglass
tank there is a steel
plate with pipe fittings for the hoses to attach. Additionally there is a "Gate valve" with a plastic pipe plug
in it. Removing the plastic pipe plug
and opening the gate valve allows straight through access to the tank. I use a brass rod that is a little longer than the tank is deep to measure the level of the fuel in the tank. Using a metal rod rather than a wooden one allows you to wipe the brass rod dry with a cloth and not have a diesel
For judging when the fuel tank
is full and to save tens of thousands of dollars in fines - I moved the fuel tank's vent from the outside of the hull
and installed it in the cabin
top side wall. I have a raised cabin
top with near vertical side wall. To the inside of the newly located diesel fuel vent I attached a Racor
Lifeguard LG100 Fuel / Air Separator which is a plastic device that allows air to vent into and out of the tank but shuts off when fuel gets to it. It is available in two sizes.
When fueling with this system air escapes through the vent under which I have positioned fuel absorbing pads - until the tank is full. At this time the fuel backs up the vent hose and the Racor
LG100 shuts off the vent preventing any fuel spillage. However, now the fuel will back up the main filler hose and it is not difficult to hear that happen. I have also positioned absorbent pads around the filler hole. Most fueling stations that I have been to have the automatic shutoff nozzles that sense the fuel backing up the filling hose and automatically turn off the nozzle. But I do not trust them much and put my ear down to the filler hole and shut off the nozzle when I hear the fuel backing up the hose.
With this system I have not had one drop of diesel go "over the side" into the water
. And an additional plus by the moving of the fuel vent to the cabin top, I have not had any sea water
make its way into the fuel tank when I am heeling over with the "rail in the water" kind of thing or waves are cresting over the side decks.