Specifications and requirements
18
Ethanol is hygroscopic (has a strong at-
traction to water). Therefore, any water that
inadvertently enters the fuel system, in-
cluding moisture that is absorbed from the
air, will mix with the ethanol in the gasoline.
If the amount of water is excessive, the eth-
anol and water mixture will separate from
the gasoline in a layer at the bottom of the
fuel tank. This ethanol and water mixture is
very corrosive to aluminum fuel tanks and
fuel system components.
The usable life span of E10 gasoline may
be shorter than the normal length of off-
season boat storage, causing starting and
running problems related to stale fuel.
For more information on using fuel containing
ethanol, visit: http://www.yamaha-mo-
tor.com
Gasoline Filtration
Yamaha outboard motors are equipped with
internal fuel filters. However, excessive water
or debris entering your engine’s fuel system
could prematurely clog the internal filters,
causing starting and running problems, fuel
system damage, and internal engine dam-
age. Therefore, it is recommended that an ex-
ternal 10-micron water-separating fuel filter
be installed on your boat and serviced fre-
quently. Consult your authorized Yamaha
dealer for a 10-micron filter that meets your
engine’s requirements.
EMU41342
Gasoline Additives
Gasoline blends change to meet automobile
emission regulations and economic condi-
tions. Additives, added by gasoline distribu-
tors, necessary for proper automobile engine
operation and durability, may not be suffi-
cient for typical boat applications. Intake
valve and combustion chamber deposits
may accumulate in boat engines more rapidly
than encountered in automotive use. In addi-
tion, gasoline used for boating will typically
age longer between refills than gasoline used
in automobiles, resulting in stale and unus-
able gasoline that may cause starting and
running problems, fuel system damage, and
internal engine damage.
Yamaha recommends the use of two Yama-
lube gasoline additives to reduce internal de-
posits and extend the storage life of gasoline.
Continuous use of Yamalube Ring Free Fuel
Additive Plus reduces harmful internal de-
posits. Yamalube Fuel Stabilizer & Condition-
er Plus added to fresh gasoline will help
protect the fuel system from varnishing while
helping to keep the gasoline’s octane level
from decreasing excessively during storage.
Other additives may also be available on the
market that may have varying degrees of ef-
fectiveness. Consult your Yamaha dealer
concerning what may work best for the local-
ly available gasoline and environmental con-
ditions.
EMU41352
Anti-fouling paint
A clean hull is required to maintain your
boat’s performance. Boats moored in the wa-
ter should be protected from marine growth
(barnacles, mussels, and marine plants). If
approved by regulations for your area, the
bottom of the hull can be coated with an anti-
fouling paint to inhibit marine growth.
Anti-fouling paints specifically formulated for
use on aluminum may be applied to the out-
board motor. The original Yamaha paint sur-
face may be scuffed lightly before applying
anti-fouling paint, but do not remove the orig-
inal paint. Removal of the original paint will in-
crease the rate of corrosion.
U6FW30E0.book Page 18 Tuesday, December 9, 2014 10:32 AM
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