Boston Whaler 270 VANTAGE, Manual

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3-6
270 Vantage
Section 3 • Systems & Components Overview & Operation
R
Additives
There is no practical additive known that can prevent
or correct phase separation. The only solution is to
keep water from accumulating in the tank.
If phase separation does occur, your only remedy is
to drain the fuel, clean and dry the tank completely
and refill with a fresh, dry load of fuel.
As a precaution, it is advisable to carry extra on-
engine
filters in case filter plugging from debris in
the fuel tank becomes a problem during boating.
Periodically inspect for the presence of water in the
fuel tank. If any is found, all water must be removed
and the tank completely dried before refilling the tank
with any fuel containing ethanol.
The use of fuels containing ethanol higher than
10 percent (E-10) can damage your engine and/
or fuel system and will void the warranty.
!
CAUTION
E85 FUELS COULD SERIOUSLY DAMAGE
YOUR ENGINES AND MUST NEVER BE
USED.
Example of Phase Separation
Fig. 3.6.1
1
2
3
4
1 2
3
4
CONDENSATION
UPPER PHASE (WATER+FUEL+ETHANOL)
LOWER PHASE (WATER+ETHANOL)
FUEL INLET TO ENGINE
Maintenance
Phase Separation
Humidity and condensation create water in your fuel
tank which can adversely effect the ethanol blended
fuel. A condition called phase separation can occur
if water is drawn into the fuel beyond the saturation
point. The presence of water in the fuel beyond the
saturation level will cause most of the ethanol in the
fuel to separate from the bulk fuel and drop to the
bottom of the tank, significantly reducing the level of
ethanol in the fuel mixture in the upper level (phase).
If the lower level (phase), consisting of water and
ethanol, is deep enough to reach the fuel inlet, it
could be pumped directly to the engine(s) and cause
significant problems. Engine problems can also result
from the reduced ethanol/fuel mixture left in the
upper phase of the tank.
Fuel Filters
Mercury already provides the appropriate level of
filtration to protect the engine from debris. The
addition of another in-line filter to the system may
create a possible flow restriction that can starve the
engine(s) of fuel. It is advisable to carry extra on-
engine
filters in case filter plugging from debris in
the fuel tank becomes a problem during boating.
Your Boston Whaler dealer will have recommendations
regarding filters that meet Mercury’s specifications.
The fuel/water separator has been determined to be
within Mercury specifications and will not restrict
the flow of adequate fuel to the engine(s).
Fuel/water Separator
Maintaining a Full Tank
It is best to maintain a full tank of fuel when the
engine is not in use. This will reduce air flow in and
out of the tank due to changes in temperature as
well as limiting exposure of the ethanol in the fuel
to humidity and condensation.