Owner`s manual
Specifications and requirements
20
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
ECM02401
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 de-
posits from a boat’s fuel system, particular-
ly 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,
including moisture that is absorbed from
the air, will mix with the ethanol in the gas-
oline. If the amount of water is excessive,
the ethanol 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 contain-
ing ethanol, visit: http://www.yamaha-mo-
tor.com
Gasoline Filtration
Yamaha outboard motors are equipped with
internal fuel filters. However, excessive wa-
ter or debris entering your engine’s fuel sys-
tem could prematurely clog the internal
filters, causing starting and running prob-
lems, fuel system damage, and internal en-
gine damage. Therefore, it is recommended
that an external 10-micron water-separating
fuel filter be installed on your boat and ser-
viced frequently. Consult your authorized
Yamaha dealer for a 10-micron filter that
meets your engine’s requirements.
EMU41341
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 rapid-
ly than encountered in automotive use. In ad-
dition, gasoline used for boating will typically
6CE-9-34-1E0.book 20 ページ 2012年11月23日 金曜日 午後1時13分