UPGRADES IN FUEL SYSTEMS
BY JOHN ADEY
BIG CHANGES UNDER THE HOOD
At the spring boat shows, as you’re looking at new boat models, ask about the fuel systems.
Important improvements are being incorporated on the inside, that are not visible on the outside
FUEL SYSTEMS IN BOATS, even boats of fairly recent vintage, have more in common with those in 1930s-era automobiles. The great news is that this is about to change. The days of overflowing fills and vents will be a thing of the past on newer-model gasoline boats.
1. There are no user-serviceable parts in this
system. The canister and valves have a similar
useful life as the ones in your car; they’re not
predicted to fail over the life of the boat.
2. Should a fuel system be suspected as a
failure point, a qualified service technician
must make the repair to ensure the integrity
of the system.
3. Do Not over-fill! Just like your car, this system can be overcome by repeated attempts
to “top off” or using a very slow fill, such as
from a jerry can. The extra gallon is not worth
the risk of having liquid fuel end up in areas
that weren’t designed for it.
For now, these systems are not an after-market solution. Rigorous industry standards,
coupled with extensive manufacturer testing,
have created a robust, dependable system
that has different characteristics based on the
model of the boat.
Automatic Gas-Pump Shutoff
By model year 2013 (July 1, 2012), gasoline-powered boats will incorporate a more advanced
fuel system designed and tested to activate the gas pump’s automatic shutoff feature, eliminating overfilling. Though no one should leave a boat unattended while fueling, the new system
takes the effort out of knowing when the boat is full. Part of this new design is a carbon canister
tucked away in the boat’s vent line and packed with a special marine-grade carbon. The carbon
scrubs the hydrocarbons from the fuel vapor, eliminating fuel odors and contributing to cleaner
air. The components also include new fuel lines and tank-construction materials that reduce
the permeation of fuel into the line and tank material.
The technology used is nothing new; the secret lies in the valves. These components are
mounted on top or in the tank and are precisely calibrated to make sure the tank fills to the
proper level every time. By reacting to the fuel level in the tank, the combination of valves
sends liquid fuel up to the fill neck, activating the shutoff feature in the gasoline pump nozzle.
Ensuring a predetermined level in the tank eliminates traditional vent leakage from the fuel
expanding due to the daily temperature rise. This also protects the carbon canister located in
the vent line from becoming saturated with liquid fuel. There are some cautions:
Improvements For Small Outboards
New EPA requirements for portable tanks are
beginning to appear on the shelves. An innovative self-sealing vent eliminates the need
to constantly open and close the traditional
screw fitting on the top of the cap. This feature
eliminates the need to open and close the vent
manually, ending the entrance of water through
an open vent. This new technology vents at
a predetermined level and even reacts to a
vacuum situation, making the collapsed tank a
thing of the past. The reason for the addition of
the automatic vent is to retain fuel vapor more
reliably than depending on users to close the
vent every time the tank is not in use.
BoatU.S. Magazine contributing editor John
Adey is VP/Technical Director of the American
Boat & Yacht Council.
“HELP STOP THE DROPS” FROM AN OLDER BOAT: KNOW YOUR FUEL TANK’S LIMIT, RESIST TOPPING OFF, AND USE
AN ABSORBENT PAD TO CATCH DROPS. FOR MORE TIPS, WWW.BOATUS.COM/FOUNDATION/CLEANWATER/DROPS/