Catalina 30 TRBS #2889 "Northern Light"

Fuel overflow sight glass

The rest of the modifications.

The fuel vent is located on the transom. If the diesel tank is filled fast and is nearly full, the foam and fuel may spurt out the vent and into the water, which can ruin a good day especially if there are particularily vocal boaters around.

I cut the vent line and inserted a piece of vinyl hose so that when I'm filling the tank I can see what's going up the vent line. Of course, the best way to prevent overflows is by knowing how much fuel you actually need and pumping very slowly as you near full.

One would have to be certain that the clear section of hose is compatible with diesel or gasoline vapors/liquid.