Fuel Tank Vents Before Full

[biggerstaff]

Q1: what could cause a fuel tank to vent gasoline from the vent hose before the tank is actually full?

BACKSTORY
My 1999 OUTRAGE 17 [II] is in pristine condition. I am not the original owner. I believe the fuel tank was replaced by a previous owner. The fuel tank is made from a gray metal. The caulk on the deck has definitely been redone.

On the fuel tank a metal plate indicates the capacity: around 54-gallons, as best I remember. I have run out all the gasoline from the fuel tank, but then I was only able to add about 27-gallons before fuel started coming out of the vent.

When I thought the tank was empty the fuel tank level gauge indicated “E”, and when fuel began to come out of the vent the gauge indicated “F.”

[jimh]

Q1: what could cause a fuel tank to vent gasoline from the vent hose before the tank is actually full?

Q2: when you were adding gasoline to the internal fuel tank, was the boat on the water or on the trailer?

[jimh]

The fuel tank is made from a gray metal.

A below-deck permanent fuel tank on a Boston Whaler would typically be made from welded aluminum. The tank would typically have a metallized foil decal that gives the manufacturer’s name, the tank model, the tank capacity, and a date. This decal or sticker would typically be in full view when a deck access plate is removed.

The usual OEM would be Florida Marine Tanks. The typical capacity for a c.1995 OUTRAGE 17 would be 32- to 34-gallons. For a c.1996 or newer OUTRAGE 17 II the typical tank capacity would be 56-gallons.

Cf.: https://continuouswave.com/whaler/refer ... hulls11-19