Fuel Requirements; Gasoline; Ring Free Fuel Additive - Yamaha VZ175 Owner's Manual

Specifications and requirements
ECM01290
NOTICE
Serious engine damage can result from
the use of lower quality oil, including
some commonly available oil brands with
"TC-W3" on their label. To avoid the risk,
use only Yamalube 2-M or, if necessary,
another outboard motor manufacturer's
factory-brand TC-W3 oil.
EMU36360

Fuel requirements

EMU36781

Gasoline

Use a good quality gasoline that meets the
minimum octane rating. If knocking or ping-
ing occurs, use a different brand of gasoline
or premium unleaded fuel. Yamaha re-
comends that you use alcohol-free (see Gas-
ohol) gasoline whenever possible.
Recommended gasoline:
Regular unleaded gasoline with a min-
imum Octane rating of 86 (Pump Oc-
tane Number) = (R+M)/2
ECM01981
NOTICE
Do not use leaded gasoline. Leaded

gasoline can seriously damage the en-
gine.
Avoid getting water and contaminants

in the fuel tank. Contaminated fuel can
cause poor performance or engine
damage. Use only fresh gasoline that
has been stored in clean containers.
Gasohol
There are two types of gasohol: gasohol con-
taining ethanol (E10) and that containing
methanol. Ethanol can be used if the ethanol
content does not exceed 10% and the fuel
meets the minimum octane ratings. E85 is a
16
fuel containing 85% ethanol and must not be
used in your outboard motor. All ethanol
blends containing more than 10% ethanol
can cause fuel system damage or cause en-
gine starting and running problems. Yamaha
does not recommend gasohol containing
methanol because it can cause fuel system
damage or engine performance problems.
It is recommended that you install a water-
separating marine fuel filter assembly (10 mi-
cron minimum) between your boat's fuel tank
and outboard motor when using ethanol.
Ethanol is known to allow moisture to be ab-
sorbed into boat fuel tanks and systems.
Moisture in the fuel can cause corrosion of
metallic fuel system components, starting
and running complaints and require addition-
al fuel system maintenance.
EMU27270

Ring Free Fuel Additive

Gasoline is a precise blend of many different
substances, each chosen to give certain
characteristics. Gasoline blends have been
changing in recent years in response to con-
cerns about pollution and resulting emis-
sions regulations. One of the most obvious
changes has been the elimination of lead
from most fuels.
As gasoline has changed, the amount of ad-
ditives such as aromatics and oxygenates
has increased. These additives are impor-
tant for the engines in passenger cars, but
they can have detrimental effects in marine
engines, because of increased deposits in
the combustion chamber. When enough de-
posits collect, piston rings begin sticking.
Performance drops and engine wear in-
creases dramatically.
While many additives available may reduce
deposits, Yamaha recommends the use of
Ring Free Fuel Additive, available from