Gasoline Additives - Yamaha F350 Owner's Manual

Specifications and requirements
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
20
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
age longer between refills than gasoline
used in automobiles, resulting in stale and
unusable gasoline that may cause starting
and running problems, fuel system damage,
and internal engine damage.
Yamaha recommends the use of two Ya-
malube gasoline additives to reduce internal
deposits and extend the storage life of gaso-
line. Continuous use of Yamalube Ring Free
Fuel Additive Plus reduces harmful internal
deposits. Yamalube Fuel Stabilizer & Condi-
tioner 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