surveying, retrofitting, repairing, owning
or operating an older boat be sure to
determine the tank material. If the tank
is fibreglass make sure there is no degradation. Surveyors and repairers should
also pay close attention to the condition
of flexible gas lines and hoses whenever
When combined with MTBE gasoline, fuel filters severely clog and even
deteriorate. The two products mixed in
boat tanks upset the vapour pressure of
the fuel causing cold start and vapour-lock problems. In isolated cases, severe
corrosion of aluminum fuel system components have been documented and
attributed to mixing the two fuel types.
To avoid this problem, boat tanks should
be run down to the lowest safe level
before taking on ethanol fuel. Fuel suppliers are in transition. Boat owners who
navigate the initial switch need to be
wary of where they take on fuel during
the season. Boat owners who trailer their
boats and fill at service stations must be
aware of what they are buying.
Marinas must also sell their stored
fuel off before adding the ethanol blend.
Reputable fuel distributors will give
dealers the steps required to prepare
storage tanks and pumping equipment.
Those include: ensuring tanks are clean;
there is no water in the system; upgrading filters to 10-micron, ethanol compatible, and water separating filters.
Because ethanol is a solvent, it will clean
dirt or contaminants from both dispensing and boat fuel systems. Boat owners
and marinas report that filters clog often
with the first few loads of fuel but the filters do remove the dirt suspended in the
fuel. Carrying spare ethanol-compatible
filters will be a must for boaters and
marinas. Boaters must have the spares
and the means to change them, including a method of safely storing the old filter and the gasoline it contains, onboard.
Ethanol, being alcohol-based,
absorbs water. Marine fuel systems are
very susceptible to water intrusion. E10
has the ability to absorb 6,000 to 7,000
PPM of water into solution and allow it
to be burned by the engine. In a 375-
litre tank, the fuel could hold about 2.5
litres of water without separation. The
problem comes when the fuel is saturated beyond its capacity to hold any more
water. Phase separation takes place and
leaves two solutions: a high concentration of water and alcohol; and, gasoline
with no oxygenate. The water-alcohol
solution is highly corrosive to aluminum
and other fuel components and the oxy-genate-shorted gasoline will cause
engine damage. The only solution is to
drain the system and start over again.
The Thin Edge of the Wedge
US Renewable Fuels Association Makes a Case for E12 on the way to E15
Engine and boat builders should be aware that the
American Renewable Fuels Association (RFA) is making
a powerful case for E12 gasoline and the effects of
increased ethanol in fuels used by boats is a significant
Currently, the Environmental Protection Agency (EPA)
is considering a formal waiver request from the ethanol
industry to allow for the blending of up to 15% ethanol
in a gallon of gasoline. The RFA strongly believes that
both the science and existing statute compel EPA to
approve this waiver. Under the law, however, EPA has
270 days to consider the request. The clock is running
and a decision is due on December 1, 2009.
In the United States however, the RFA is promoting
the idea that fuel suppliers can immediately take steps
to increase ethanol use.
Their reasoning is that the EPA has authority to define
E12 (12% ethanol/88% gasoline) blends as “
substantially similar” to fuels used in certified motor vehicles.
The basis for this conclusion is that the weight percentage of oxygen that EPA allows in oxygenated gasoline actually equates to an oxygen percentage that would
be present in 12% ethanol blends. Ethanol as a fuel
additive is an oxygenate. Including ethanol raises the
oxygen content of gasoline, causing for a cleaner, more
complete combustion of gasoline in vehicles with closed
fuel tanks and systems.
The fuel systems in boats are open to ventilation and
adding 2% more ethanol will just increase the absorption
of water from the surrounding air, accelerating the process of phase separation.
“We need not wait until EPA decides on the formal
E15 waiver request to increase the amount of ethanol we
use,” said RFA President Bob Dinneen. “This interim
and legally supported step of approving E12 blends
would provide an immediate boost to America’s ethanol
producers and provide gasoline marketers the flexibility
they need to meet the requirements of the Renewable
Fuels Standard and capitalize on the cost savings associated with increased ethanol blending. “
The NMMA is aggressively opposing the move to E15
but the RFA lobby is powerful and marine use of fuel is
miniscule by comparison to vehicular use.
Boating Industry Canada will continue to cover this
issue as it develops.