Specifications and requirements
20
without Ethanol and gasoline with Ethanol,
which is typically referred to as E10 gasoline.
According to federal regulations, E10 gaso-
line may contain up to 10% Ethanol.
A high quality gasoline without Ethanol is the
preferred fuel for your Yamaha outboard mo-
tor. However, if gasoline with Ethanol is the
only fuel available in your area, your Yamaha
outboard motor is calibrated to run properly
on fresh E10 gasoline that meets the mini-
mum octane requirement specified for this
model.
NOTICE
ECM02402
Never use a gasoline for your outboard
motor that contains more than 10% Etha-
nol, such as E15 which contains 15% Eth-
anol or E85 which contains 85% Ethanol,
or gasoline containing any amount of
Methanol. These fuels can cause starting
and running problems, as well as serious
fuel system and internal engine damage.
Gasoline containing ethanol has several
properties that may cause boat fuel system
problems.
Ethanol is a strong solvent (cleaning agent)
that can clean gum and varnish deposits
from a boat’s fuel system, particularly in
older boats, as well as tanks and pipes
used in gasoline distribution. These re-
leased deposits contaminate the fuel and
can cause problems, such as clogged fuel
filters, carburetors, or fuel injectors, which
could result in engine damage.
Ethanol may dissolve resins used in the
construction of fiberglass fuel tanks. The
dissolved resins contaminate the fuel and
can cause problems, such as clogged fuel
filters, carburetors, or fuel injectors, which
could result in engine damage.
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-
U6DR38E0.book Page 20 Tuesday, November 27, 2018 2:08 PM
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Yamaha
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