Start-In-Gear Protection; Engine Oil Requirements; Fuel Requirements; Gasoline - Yamaha 25 Owner's Manual

Specifications and requirements
ler for a smaller operating load and a smaller
pitch propeller for a heavier load. If you carry
loads that vary widely, chose the propeller
that lets the engine run in the proper range
for your maximum load but remember that
you may need to reduce your throttle setting
to stay within the recommended engine
speed range when carrying lighter loads.
For instructions on propeller removal and in-
stallation, see page 62.
1. Propeller diameter in inches
2. Propeller pitch in inches
3. Type of propeller (propeller mark)
EMU25770

Start-in-gear protection

Yamaha outboard motors or Yamaha-ap-
proved remote control units are equipped
with start-in-gear protection device(s). This
feature permits the engine to be started only
when it is in neutral. Always select neutral
before starting the engine.
EMU25651

Engine oil requirements

Recommended engine oil:
YAMALUBE 2-stroke outboard motor
oil
If the recommended engine oil is not avail-
able, another 2-stroke engine oil with an
NMMA-certified TC-W3 rating may be used.
16
x -
1 2 3
ZMU04605
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
Gasohol) 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
G
gasoline can seriously damage the en-
gine.
Avoid getting water and contaminants
G
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
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