Yamaha 8 User manual

8
OWNER’S MANUAL
6M8-F8199-1E
U.S.A.Edition
LIT-18626-08-33
U6M81EMC09.4.210:05AMページ1

EMU25062
ZMU01690
Read this manual carefully before operating this outboard motor. Keep this
manual onboard in a waterproof bag when boating. This manual should stay
with the outboard motor if it is sold.
U6M81EMC09.4.210:05AMページ2

Important manual information
EMU31283
To the owner
Thank you for choosing a Yamaha outboard
motor. This Owner’s Manual contains infor-
mation needed for proper operation, mainte-
nance and care. A thorough understanding
of these simple instructions will help you ob-
tain maximum enjoyment from your new
Yamaha. If you have any question about the
operation or maintenance of your outboard
motor, please consult a Yamaha dealer.
In this Owner’s Manual particularly important
information is distinguished in the following
ways.
: This is the safety alert symbol. It is
used to alert you to potential personal injury
hazards. Obey all safety messages that fol-
low this symbol to avoid possible injury or
death.
WARNING
EWM00781
A WARNING indicates a hazardous situa-
tion which, if not avoided, could result in
death or serious injury.
NOTICE
ECM00701
A NOTICE indicates special precautions
that must be taken to avoid damage to the
outboard motor or other property.
T
IP:
A TIP provides key information to make pro-
cedures easier or clearer.
Yamaha continually seeks advancements in
product design and quality. Therefore, while
this manual contains the most current prod-
uct information available at the time of print-
ing, there may be minor discrepancies
between your machine and this manual. If
there is any question concerning this manu-
al, please consult your Yamaha dealer.
T
IP:
The 8MH and the standard accessories are
used as a base for the explanations and illus-
trations in this manual. Therefore some
items may not apply to every model.
EMU25131
8
OWNER’S MANUAL
©2009 by Yamaha Motor Corporation, USA
1st Edition, March 2009
All rights reserved.
Any reprinting or unauthorized use
without the written permission of
Yamaha Motor Corporation, USA
is expressly prohibited.
Printed in France
P/N LIT-18626-08-33

Table of contents
Safety information............................. 1
Outboard motor safety .................... 1
Propeller............................................ 1
Rotating parts.................................... 1
Hot parts ........................................... 1
Electric shock.................................... 1
Engine shut-off cord (lanyard)........... 1
Gasoline............................................ 1
Gasoline exposure and spills ............ 1
Carbon monoxide.............................. 1
Modifications ..................................... 2
Boating safety ................................. 2
Alcohol and drugs ............................. 2
Personal flotation devices ................. 2
People in the water ........................... 2
Passengers ....................................... 2
Overloading....................................... 2
Avoid collisions ................................. 2
Weather ............................................ 3
Accident reporting ............................. 3
Boat education and training .............. 3
Passenger training ............................ 3
Boating safety publications ............... 3
Laws and regulations ........................ 3
Boating organizations...................... 4
Basic boating rules (Rules of the
road) .............................................. 4
Steering and sailing rules and
sound signals.................................. 4
Rules when encountering vessels .... 5
Other special situations..................... 6
General information .......................... 9
Identification numbers record.......... 9
Outboard motor serial number .......... 9
Read manuals and labels.............. 10
Warning labels ................................ 10
Specifications and
requirements.................................... 13
Specifications ................................ 13
Installation requirements ............... 14
Boat horsepower rating................... 14
Mounting motor ............................... 14
Propeller selection......................... 14
Start-in-gear protection ................. 15
Engine oil requirements ................ 15
Fuel requirements......................... 15
Gasoline .......................................... 15
Ring Free Fuel Additive................... 16
Muddy or acidic water................... 16
Anti-fouling paint ........................... 16
Motor disposal requirements......... 16
Emergency equipment.................. 16
Emission control information......... 16
North American models................... 16
Components .................................... 18
Components diagram.................... 18
Fuel tank ......................................... 18
Fuel joint.......................................... 19
Fuel gauge ...................................... 19
Fuel tank cap................................... 19
Air vent screw.................................. 19
Tiller handle..................................... 19
Gear shift lever................................19
Throttle grip ..................................... 19
Throttle indicator ............................. 20
Throttle friction adjuster................... 20
Engine shut-off cord (lanyard) and
clip................................................. 20
Engine stop button ..........................21
Choke knob for pull type .................21
Manual starter handle .....................21
Steering friction adjuster .................21
Trim rod (tilt pin) .............................. 22
Shallow water lever ......................... 22
Tilt support knob.............................. 22
Cowling lock lever(s) (turn type)...... 22
Installation ....................................... 23
Installation..................................... 23
Mounting the outboard motor .......... 23
Clamping the outboard motor.......... 24
Operation ......................................... 26
First-time operation....................... 26
Breaking in engine ..........................26
Getting to know your boat ...............26
Checks before starting engine ...... 26
Fuel level ......................................... 27
Remove cowling .............................. 27
Fuel system ..................................... 27
Controls ........................................... 27

Table of contents
Engine shut-off cord (lanyard)......... 27
Oil.................................................... 27
Engine............................................. 28
Install cowling.................................. 28
Filling fuel and engine oil............... 28
Filling fuel for portable tank............. 28
Gasoline and oil mixing (100:1) ...... 29
Operating engine........................... 30
Sending fuel (portable tank)............ 30
Starting engine................................ 31
Checks after starting engine ......... 33
Cooling water .................................. 33
Warming up engine ....................... 33
Choke start models ......................... 33
Checks after engine warm-up ....... 34
Shifting ............................................ 34
Stop switches.................................. 34
Shifting .......................................... 34
Stopping boat ................................ 35
Stopping engine ............................ 35
Procedure ....................................... 35
Trimming outboard motor.............. 36
Adjusting trim angle for manual tilt
models .......................................... 36
Adjusting boat trim .......................... 37
Tilting up and down ....................... 38
Procedure for tilting up (manual tilt
models) ......................................... 38
Procedure for tilting down (manual
tilt models) .................................... 39
Shallow water................................ 39
Cruising in shallow water (manual
tilt models) .................................... 39
Cruising in other conditions........... 40
Maintenance..................................... 41
Transporting and storing
outboard motor ............................ 41
Clamp screw mounting models....... 41
Storing outboard motor ................... 41
Procedure ....................................... 42
Lubrication ...................................... 43
Cleaning and anticorrosion
measures ...................................... 43
Cleaning the outboard motor .......... 43
Checking painted surface of
motor............................................. 43
Periodic maintenance ................... 43
Replacement parts .......................... 44
Maintenance interval guidelines......44
Maintenance chart 1........................ 45
Maintenance chart 2........................ 47
Greasing.......................................... 48
Cleaning and adjusting spark
plug ............................................... 48
Checking fuel filter........................... 49
Inspecting idling speed.................... 49
Checking wiring and connectors .....50
Checking propeller .......................... 50
Removing propeller ......................... 51
Installing propeller ........................... 51
Changing gear oil ............................ 51
Cleaning fuel tank ...........................53
Inspecting and replacing
anode(s)........................................ 53
Trouble Recovery............................ 55
Troubleshooting ............................ 55
Temporary action in emergency ... 58
Impact damage ............................... 58
Starter will not operate ....................58
Emergency starting engine .............59
Treatment of submerged motor .... 60
Consumer information ................... 61
YAMAHA MOTOR
CORPORATION, U.S.A.
OUTBOARD MOTOR TWO
YEAR LIMITED WARRANTY ..... 61
IMPORTANT WARRANTY
INFORMATION IF YOU USE
YOUR YAMAHA OUTSIDE
THE USA OR CANADA .............. 64

1
Safety information
EMU33622
Outboard motor safety
Observe these precautions at all times.
EMU36501
Propeller
People can be injured or killed if they come
in contact with the propeller. The propeller
can keep moving even when the motor is in
neutral, and sharp edges of the propeller can
cut even when stationary.
●
Stop the engine when a person is in the
water near you.
●
Keep people out of reach of the propeller,
even when the engine is off.
EMU33630
Rotating parts
Hands, feet, hair, jewelry, clothing, PFD
straps, etc. can become entangled with inter-
nal rotating parts of the engine, resulting in
serious injury or death.
Keep the top cowling in place whenever pos-
sible. Do not remove or replace the cowling
with the engine running.
Only operate the engine with the cowling re-
moved according to the specific instructions
in the manual. Keep hands, feet, hair, jewel-
ry, clothing, PFD straps, etc. away from any
exposed moving parts.
EMU33640
Hot parts
During and after operation, engine parts are
hot enough to cause burns. Avoid touching
any parts under the top cowling until the en-
gine has cooled.
EMU33650
Electric shock
Do not touch any electrical parts while start-
ing or operating the engine. They can cause
shock or electrocution.
EMU33671
Engine shut-off cord (lanyard)
Attach the engine shut-off cord so that the
engine stops if the operator falls overboard
or leaves the helm. This prevents the boat
from running away under power and leaving
people stranded, or running over people or
objects.
Always attach the engine shut-off cord to a
secure place on your clothing or your arm or
leg while operating. Do not remove it to leave
the helm while the boat is moving. Do not at-
tach the cord to clothing that could tear
loose, or route the cord where it could be-
come entangled, preventing it from function-
ing.
Do not route the cord where it is likely to be
accidentally pulled out. If the cord is pulled
during operation, the engine will shut off and
you will lose most steering control. The boat
could slow rapidly, throwing people and ob-
jects forward.
EMU33810
Gasoline
Gasoline and its vapors are highly flam-
mable and explosive.
Always, refuel ac-
cording to the procedure on page 30 to
reduce the risk of fire and explosion.
EMU33820
Gasoline exposure and spills
Take care not to spill gasoline. If gasoline
spills, wipe it up immediately with dry rags.
Dispose of rags properly.
If any gasoline spills onto your skin, immedi-
ately wash with soap and water. Change
clothing if gasoline spills on it.
If you swallow gasoline, inhale a lot of gaso-
line vapor, or get gasoline in your eyes, get
immediate medical attention. Never siphon
fuel by mouth.
EMU33900
Carbon monoxide
This product emits exhaust gases which
contain carbon monoxide, a colorless, odor-
less gas which may cause brain damage or

Safety information
2
death when inhaled. Symptoms include nau-
sea, dizziness, and drowsiness. Keep cock-
pit and cabin areas well ventilated. Avoid
blocking exhaust outlets.
EMU33780
Modifications
Do not attempt to modify this outboard mo-
tor. Modifications to your outboard motor
may reduce safety and reliability, and render
the outboard unsafe or illegal to use.
EMU33740
Boating safety
This section includes a few of the many im-
portant safety precautions that you should
follow when boating.
EMU33710
Alcohol and drugs
Never operate after drinking alcohol or tak-
ing drugs. Intoxication is one of the most
common factors contributing to boating fatal-
ities.
EMU33720
Personal flotation devices
Have an approved personal flotation device
(PFD) on board for every occupant. Yamaha
recommends that you must wear a PFD
whenever boating. At a minimum, children
and non-swimmers should always wear
PFDs, and everyone should wear PFDs
when there are potentially hazardous boat-
ing conditions.
EMU33731
People in the water
Always watch carefully for people in the wa-
ter, such as swimmers, skiers, or divers,
whenever the engine is running. When
someone is in the water near the boat, shift
into neutral and stop the engine.
Stay away from swimming areas. Swimmers
can be hard to see.
The propeller can keep moving even when
the motor is in neutral. Stop the engine when
a person is in the water near you.
EMU33751
Passengers
Consult your boat manufacturer’s instruc-
tions for details about appropriate passenger
locations in your boat and be sure all pas-
sengers are positioned properly before ac-
celerating and when operating above an idle
speed. Standing or sitting in non-designated
locations may result in being thrown either
overboard or within the boat due to waves,
wakes, or sudden changes in speed or direc-
tion. Even when people are positioned prop-
erly, alert your passengers if you must make
any unusual maneuver. Always avoid jump-
ing waves or wakes.
EMU33760
Overloading
Do not overload the boat. Consult the boat
capacity plate or boat manufacturer for max-
imum weight and number of passengers. Be
sure that weight is properly distributed ac-
cording to the boat manufacturers instruc-
tions. Overloading or incorrect weight
distribution can compromise the boats han-
dling and lead to an accident, capsizing or
swamping.
EMU33772
Avoid collisions
Scan constantly for people, objects, and oth-
er boats. Be alert for conditions that limit your
visibility or block your vision of others.
ZMU06025

Safety information
3
Operate defensively at safe speeds and
keep a safe distance away from people, ob-
jects, and other boats.
●
Do not follow directly behind other boats or
waterskiers.
●
Avoid sharp turns or other maneuvers that
make it hard for others to avoid you or un-
derstand where you are going.
●
Avoid areas with submerged objects or
shallow water.
●
Ride within your limits and avoid aggres-
sive maneuvers to reduce the risk of loss
of control, ejection, and collision.
●
Take early action to avoid collisions. Re-
member, boats do not have brakes, and
stopping the engine or reducing throttle
can reduce the ability to steer. If you are
not sure that you can stop in time before
hitting an obstacle, apply throttle and turn
in another direction.
EMU33790
Weather
Stay informed about the weather. Check
weather forecasts before boating. Avoid
boating in hazardous weather.
EMU33800
Accident reporting
Boat operators are required by law to file a
Boating Accident Report with their state
boating law enforcement agency if their boat
is involved in any of the following accidents:
1. There is loss of life or probable loss of
life.
2. There is personal injury that requires
medical attention beyond first aid.
3. There is property damage to boats or
other property over a certain amount.
4. There is complete loss of a boat.
Contact local law enforcement personnel if a
report is necessary.
EMU33870
Boat education and training
Operators should take a boating safety
course. This may be required in your state.
Many of the organizations listed in the next
section can provide information about cours-
es in your area.
You may also want to consider an Internet-
based program for basic boater education.
The Online Boating Safety Course provided
by the BoatU.S. Foundation, is approved by
the National Association of State Boating
Law Administrators (NASBLA) and recog-
nized by the United States Coast Guard.
Most, but not all, states accept this course to
meet their minimum requirements. While it
cannot replace an in-depth course such as
one offered by the U.S. Coast Guard, U.S.
Power Squadron, or other organization, this
online course does provide a general over-
view of the basics in boating safety, require-
ments, navigation, and operation. Upon
successful completion of the course, the
user can download a certificate of comple-
tion immediately or, for a small charge, re-
quest one by mail. To take this free course,
go to boatus.org.
EMU33880
Passenger training
Make sure at least one other passenger is
trained to operate the boat in the event of an
emergency.
EMU33890
Boating safety publications
Be informed about boating safety. Additional
publications and information can be obtained
from many boating organizations.
EMU33590
Laws and regulations
Know the marine laws and regulations where
you will be boating- and obey them. Several
sets of rules prevail according to geographic

Safety information
4
location, but all are basically the same as the
International Rules of the Road. The rules
presented in the following section are con-
densed- and have been provided for your
convenience only.
Contact the U.S. Coast Guard, the National
Association of State Boating Law Adminis-
trators, or your local Power Squadron for a
complete set of rules governing the waters in
which you will be using your boat.
EMU33681
Boating organizations
The following organizations provide boating
safety training and information about boating
safety and laws.
United States Coast Guard
Consumer Affairs Staff (G-BC)
Office of Boating, Public, and Consumer Af-
fairs
U.S. Coast Guard Headquarters
Washington, D.C. 20593-0001
Boating Safety Hotline: 1-800-368-5647
www.uscgboating.org
United States Power Squadrons
1-888-FOR-USPS (1-888-367-8777)
www.usps.org
Boat Owners Association of The United
States
1-800-336-BOAT (1-800-336-2628)
www.boatus.com
National Association of State Boating
Law Administrators (NASBLA)
1500 Leestown Road, Suite 330
Lexington, KY 40511 859-225-9497
www.nasbla.org
National Marine Manufacturers Associa-
tion (NMMA)
200 East Randolph Drive
Suite 5100
Chicago, IL 60601
www.nmma.org
Marine Retailers Association of America
155 N. Michigan Ave. Chicago,
IL 60304
www.mraa.com
EMU33690
Basic boating rules (Rules of
the road)
Just as there are rules that apply when you
are driving on streets and highways, there
are waterway rules that apply when you are
driving your boat. These rules are used inter-
nationally. (For USA: and are also enforced
by the United States Coast Guard and local
agencies.) You should be aware of these
rules, and follow them whenever you en-
counter another vessel on the water.
EMU33700
Steering and sailing rules and sound
signals
Whenever two vessels on the water meet
one another, one vessel has the right-of-
way; it is called the “stand-on”vessel. The
vessel that does not have the right-of-way is
called the “give-way”or “burdened”vessel.
These rules determine which vessel has the
right-of-way, and what each vessel should
do.
Stand-on vessel
The vessel with the right-of-way has the duty
to continue its course and speed, except to
avoid an immediate collision. When you
maintain your direction and speed, the other

Safety information
5
vessel will be able to determine how best to
avoid you.
Give-way vessel
The vessel that does not have the right-of-
way has the duty to take positive and timely
action to stay out of the way of the Stand-On
vessel. Normally, you should not cross in
front of the vessel with the right-of-way. You
should slow down or change directions brief-
ly and pass behind the other vessel. You
should always move in such a way that the
operator of the other vessel can see what
you are doing.
“ The general prudential rule ”
This rule is called Rule 2 in the International
Rules and says,
“In obeying and construing these rules due
regard shall be had to all dangers of naviga-
tion and collision, and to any special circum-
stances, which may render a departure from
the above rules necessary in order to avoid
immediate danger.”
In other words, follow the standard rules ex-
cept when a collision will occur unless both
vessels try to avoid each other. If that is the
case, both vessels become “Give-Way ”
vessels.
EMU25521
Rules when encountering vessels
There are three main situations that you may
encounter with other vessels which could
lead to a collision unless the Steering Rules
are followed:
Meeting:
(you are approaching another ves-
sel head-on)
Crossing:
(you are traveling across the oth-
er vessel’s path)
Overtaking:
(you are passing or being
passed by another vessel)
In the following illustration, your boat is in the
center. You should give the right-of-way to
any vessels shown in white area (you are the
Give-Way vessel). Any vessels in the shad-
ed area must yield to you (they are the Give-
Way vessels). Both you and the meeting
vessel must alter course to avoid each other.
Meeting
If you are meeting another power vessel
head on, and are close enough to run the risk
of collision, neither of you has the right-of-
way Both of you should alter course to avoid
an accident. You should keep the other ves-
sel on your port (left) side. This rule doesn’t
apply if both of you will clear one another if
you continue on your set course and speed.
Crossing
When two power driven vessels are crossing
each other’s path close enough to run the
risk of collision, the vessel which has the oth-
er on the starboard (right) side must keep out
of the way of the other. If the other vessel is
on your right, you must keep out of its way;

Safety information
6
you are the Give-Way vessel. If the other
vessel is on your port (left) side, remember
that you should maintain course and direc-
tion, provided the other vessel gives you the
right-of-way as it should.
Overtaking
If you are passing another vessel, you are
the “Give-Way”vessel. This means that the
other vessel is expected to maintain its
course and speed. You must stay out of its
way until you are clear of it. Likewise, if an-
other vessel is passing you, you should
maintain your speed and direction so that the
other vessel can steer itself around you.
EMU25531
Other special situations
There are three other rules you should be
aware of when driving your boat around oth-
er vessels.
Narrow channels and bends
When navigating in narrow channels, you
should keep to the right when it is safe and
practical to do so. If the operator of a power-
driven vessel is preparing to go around a
bend that may obstruct the view of other wa-
ter vessels, the operator should sound a pro-
longed blast on the whistle (4 to 6 seconds).
If another vessel is around the bend, it too
should sound the whistle. Even if no reply is
heard, however, the vessel should still pro-
ceed around the bend with caution. If you
navigate such waters with your boat, you will
need to carry a portable air horn, available
from local marine supply stores.
Fishing vessel right-of-way
All vessels that are fishing with nets, lines or
trawls are considered to be “fishing vessels”
under the International Rules. Vessels with
trolling lines are not considered fishing ves-
sels. Fishing vessels have the right-of-way
regardless of position. Fishing vessels can-
not, however, impede the passage of other
vessels in narrow channels.
Sailing vessel right-of-way
Sailing vessels should normally be given the
right-of-way. The exceptions to this are:
1. When the sailing vessel is overtaking
the power-driven vessel, the power-driv-
en vessel has the right-of-way.
2. Sailing vessels should keep clear of any
fishing vessel.
3. In a narrow channel, a sailing vessel
should not hamper the safe passage of
a power-driven vessel that can navigate
only in such a channel.
Reading buoys and other markers
The waters of the United States are marked
for safe navigation by the lateral system of
buoyage. Simply put, buoys and markers
have an arrangement of shapes, colors,
numbers and lights to show which side of the
buoy a boater should pass on when navigat-
ing in a particular direction. The markings on
these buoys are oriented from the perspec-
tive of being entered from seaward (the boat-
er is going towards the port). This means that
red buoys are passed on the starboard
(right) side when proceeding from open wa-
ter into port, and black buoys are to port (left)
side. When navigating out of port, your posi-
tion with respect to the buoys should be re-
versed; red buoys should be to port and

Safety information
7
black buoys to starboard.
Many bodies of water used by boaters are
entirely within the boundaries of a particular
state. The Uniform State Waterway Marking
System has been devised for these waters.
This system uses buoys and signs with dis-
tinctive shapes and colors to show regulato-
ry or advisory information. These markers
are white with black letters and orange
boarders. They signify speed zones, restrict-
ed areas, danger areas, and general infor-
mation.
Remember, markings may vary by geo-
graphic location. Always consult local boat-
ing authorities before driving your boat in
unfamiliar waters.

Safety information
8
ZMU01708

9
General information
EMU25171
Identification numbers record
EMU25183
Outboard motor serial number
The outboard motor serial number is
stamped on the label attached to the port
side of the clamp bracket.
Record your outboard motor serial number in
the spaces provided to assist you in ordering
spare parts from your Yamaha dealer or for
reference in case your outboard motor is sto-
len.
1. Outboard motor serial number location
1
ZMU02836

General information
10
EMU33520
Read manuals and labels
Before operating or working on this motor:
●
Read this manual.
●
Read any manuals supplied with the boat.
●
Read all labels on the outboard motor and the boat.
If you need any additional information, contact your Yamaha dealer.
EMU33831
Warning labels
If these labels are damaged or missing, contact your Yamaha dealer for replacements.
8
1
2
3
ZMU06306

General information
11
12
3
ZMU05697

General information
12
EMU35132
Symbols
The following symbols mean as follows.
Notice/Warning
Read Owner’s Manual
Hazard caused by continuous rotation
Electrical hazard
ZMU05696
ZMU05664
ZMU05665
ZMU05666

13
Specifications and requirements
EMU31480
Specifications
T
IP:
“(AL)”stated in the specification data below
represents the numerical value for the alumi-
num propeller installed.
Likewise, “(SUS)”represents the value for
stainless steel propeller installed and “(PL)”
for plastic propeller installed.
EMU2821E
Dimension:
Overall length:
802 mm (31.6 in)
Overall width:
343 mm (13.5 in)
Overall height S:
977 mm (38.5 in)
Transom height S:
436 mm (17.2 in)
Weight (AL) S:
27.0 kg (60 lb)
Performance:
Full throttle operating range:
4500–5500 r/min
Maximum output:
5.9 kW@5000 r/min
(8 HP@5000 r/min)
Idling speed (in neutral):
900
±
50 r/min
Engine:
Type:
2-stroke L
Displacement:
165.0 cm
3
Bore
×
stroke:
50.0
×
42.0 mm (1.97
×
1.65 in)
Ignition system:
CDI
Spark plug (NGK):
B7HS-10
Spark plug gap:
0.9–1.0 mm (0.035–0.039 in)
Control system:
Tiller
Starting system:
Manual
Starting carburetion system:
Choke valve
Alternator output:
80 W
Drive unit:
Gear positions:
Forward-neutral-reverse
Gear ratio:
2.08 (27/13)
Trim and tilt system:
Manual tilt
Propeller mark:
N
Fuel and oil:
Recommended fuel:
Regular unleaded gasoline
Min. pump octane:
86
Fuel tank capacity:
12 L (3.17 US gal, 2.64 Imp.gal)
Recommended engine oil:
YAMALUBE 2-stroke outboard motor
oil
Fuel:oil ratio:
Regular gasoline:
100 :1
Lubrication:
Pre-mixed fuel and oil
Recommended gear oil:
Hypoid gear oil SAE#90
Gear oil quantity:
0.160 L (0.169 US qt, 0.141 Imp.qt)
Tightening torque for engine:
Spark plug:
25.0 Nm (2.55 kgf-m, 18.4 ft-lb)

Specifications and requirements
14
Propeller nut:
17.0 Nm (1.73 kgf-m, 12.5 ft-lb)
EMU33554
Installation requirements
EMU33563
Boat horsepower rating
WARNING
EWM01560
Overpowering a boat can cause severe
instability.
Before installing the outboard motor(s), con-
firm that the total horsepower of your mo-
tor(s) does not exceed the boats maximum
horsepower rating. See the boat’s capacity
plate or contact the manufacturer.
EMU33571
Mounting motor
WARNING
EWM01570
●
Improper mounting of the outboard mo-
tor could result in hazardous condi-
tions such as poor handling, loss of
control, or fire hazards.
●
Because the motor is very heavy, spe-
cial equipment and training is required
to mount it safely.
Your dealer or other person experienced in
proper rigging should mount the motor using
correct equipment and complete rigging in-
structions. For further information, see page
23.
EMU34192
Propeller selection
Next to selecting an outboard, choosing the
right propeller is one of the most important
purchasing decisions a boater can make.
The type, size, and design of your propeller
have a direct impact on acceleration, top
speed, fuel economy, and even engine life.
Yamaha designs and manufactures propel-
lers for every Yamaha outboard motor and
every application.
Your outboard motor came with a Yamaha
propeller chosen to perform well over a
range of applications, but there may be uses
where a different propeller would be more
appropriate.
Your Yamaha dealer can help you select the
right propeller for your boating needs. Select
a propeller that will allow the engine to reach
the middle or upper half of the operating
range at full throttle with the maximum boat-
load. Generally, chose a larger pitch propel-
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 50.
1. Propeller diameter in inches
2. Propeller pitch in inches
3. Type of propeller (propeller mark)
ZMU04604
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123

Specifications and requirements
15
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
If the recommended engine oil is not avail-
able, another 2-stroke engine oil with an
NMMA-certified TC-W3 rating may be used.
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.
NOTICE
ECM01981
●
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
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
micron minimum) between your boat’s fuel
tank and outboard motor when using etha-
nol. Ethanol is known to allow moisture to be
absorbed 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.
1. Propeller diameter in inches
2. Propeller pitch in inches
3. Type of propeller (propeller mark)
Recommended engine oil:
YAMALUBE 2-stroke outboard motor
oil
ZMU04605
-
x
123
Recommended gasoline:
Regular unleaded gasoline with a min-
imum Octane rating of 86 (Pump Oc-
tane Number) = (R+M)/2
Other manuals for 8
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