Yamaha 25A, 30A User Manual

OWNER’S MANUAL

25A
30A

U.S.A.Edition

LIT-18626-04-54

EMU01449

TO THE OWNER

Thank you for choosing a Yamaha out­board motor. This Owner’s manual con­tains information needed for proper oper­ation, maintenance and care. A thorough
understanding of these simple instruc­tions will help you obtain 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.

The Safety Alert Symbol means
ATTENTION! BECOME ALERT!

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YOUR SAFETY IS INVOLVED!

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cC

A CAUTION indicates special precautions
that must be taken to avoid damage to
the outboard motor.

NOTE:

A NOTE provides key information to make
procedures easier or clearer.

* Yamaha continually seeks advance-

ments in product design and quality.
Therefore, while this manual contains
the most current product information
available at the time of printing, there
may be minor discrepancies between
your machine and this manual. If there
is any question concerning this manual,
please consult your Yamaha dealer.

w

Failure to follow WARNING instructions
could result in severe injury or death to
the machine operator, a bystander, or a
person inspecting or repairing the out­board motor.

EMU01446

25A/30A

OWNER'S MANUAL

©2001 by Yamaha Motor Corporation, USA

1st Edition, April 2001

All rights reserved.

Any reprinting or unauthorized use

without the written permission of

Yamaha Motor Corporation, USA

is expressly prohibited.

Printed in Japan

P/N LIT-18626-04-54

NOTE:

The 25MH, 30EH, 30ER and their standard
accessories are used as a base for the
explanations and illustrations in this man­ual. Therefore, some items may not apply
to every model.

EMA20010

CONTENTS

E

GENERAL INFORMATION

BASIC COMPONENTS

OPERATION

MAINTENANCE

1

2

3

4

TROUBLE RECOVERY

INDEX

READ THIS OWNER’S MANUAL CAREFULLY

BEFORE OPERATING YOUR OUTBOARD MOTOR.

5

6

EMB00010

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Chapter 1

1

GENERAL

INFORMATION

IDENTIFICATION NUMBERS RECORD ..1-1

Outboard motor serial number...........1-1

Key number...........................................1-1

EMISSION CONTROL INFORMATION...1-2

SAFETY INFORMATION..........................1-3

IMPORTANT LABELS ..............................1-5

BASIC BOATING RULES .........................1-6

FUELING INSTRUCTIONS.....................1-10

Gasoline (petrol).................................1-11

Engine oil ............................................1-11

BATTERY REQUIREMENT ....................1-12

PROPELLER SELECTION .......................1-13

START-IN-GEAR PROTECTION ............1-14

2

3

4

5

6

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904011*

123

YAMAHA

q

EMU00005

IDENTIFICATION NUMBERS

RECORD

EMU00007

OUTBOARD MOTOR SERIAL NUM­BER

YAMAHA MOTOR CO., LTD.
MADE IN JAPAN
PAYS D'ORIGINE JAPON

1

401012

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 stolen.

1 Outboard motor serial number

EMU00008

KEY NUMBER

If a main key switch is equipped with the
motor, the key identification number is
stamped on your key as shown in the
illustration. Record this number in the
space provided for reference in case you
need a new key.

1 Key number

1-1

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EMISSION CONTROL INFORMATION

ENGINE FAMILY :

THIS ENGINE CONFORMS TO 2001 U.S. EPA REGULATIONS FOR MARINE SI ENGINES.
FELs :
SPARK PLUG :

IDLE SPEED :

rpm IN NEUTRAL

SPARK PLUG GAP (mm) :

g/kw-hr

Manufactured:

25

25-3/30

2

1

1

2

108021

108022

EMU01385

EMISSION CONTROL

INFORMATION

EMU01386

NORTH AMERICAN MODELS

This engine conforms to U.S. Environ­mental Protection Agency (EPA) regula­tions for marine SI engines. See the label
affixed to your engine for details.

Approval label of Emission control
certificate

This label is attached to the bottom cowl­ing.

1 Emission control information label

Existing Technology ; N/A

Manufactured date label

This label is attached to the clamp bracket
or the swivel bracket.

2 Manufactured date label

1-2

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EMU00917

SAFETY

Q

8 Before mounting or operating the out-

board motor, read this entire manual.
Reading it should give you an under­standing of the motor and its operation.

8 Before operating the boat, read any

owner’s or operator’s manuals supplied
with it and all labels. Be sure you under­stand each item before operating.

8 Do not overpower the boat with this

outboard motor. Overpowering the
boat could result in loss of control. The
rated power of the outboard should be
equal to or less than the rated horse­power capacity of the boat. If the rated
horsepower capacity of the boat is
unknown, consult the dealer or boat
manufacturer.

8 Do not modify the outboard. Modifica-

tions could make the motor unfit or
unsafe to use.

8 Never operate after drinking alcohol or

taking drugs. About 50% of all boating
fatalities involve intoxication.

8 Have an approved personal flotation

device (PFD) on board for every occu­pant. It is a good idea to 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 boating conditions.

8 Gasoline is highly flammable, and its

vapors are flammable and explosive.
Handle and store gasoline carefully.
Make sure there are no gas fumes or
leaking fuel before starting the engine.

INFORMATION

8 This product emits exhaust gases which

contain carbon monoxide, a colorless,
odorless gas which may cause brain
damage or death when inhaled. Symp­toms include nausea, dizziness, and
drowsiness. Keep cockpit and cabin
areas well ventilated. Avoid blocking
exhaust outlets.

8 Check throttle, shift, and steering for

proper operation before starting the
engine.

8 Attach the engine stop switch lanyard

to a secure place on your clothing, or
your arm or leg while operating. If you
accidentally leave the helm, the lanyard
will pull from the switch, stopping the
engine.

8 Know the marine laws and regulations

where you will be boating - and obey
them. Refer to the “RULES OF THE
ROAD” section for basic boating rules.

8 Stay informed about the weather.

Check weather forecasts before boating.
Avoid boating in hazardous weather.

8 Tell someone where you are going:

leave a Float Plan with a responsible
person. Be sure to cancel the Float Plan
when you return.

8 Use common sense and good judgment

when boating. Know your abilities, and
be sure you understand how your boat
handles under the different boating
conditions you may encounter. Operate
within your limits, and the limits of your
boat. Always operate at safe speeds,
and keep a careful watch for obstacles
and other traffic.

8 Always watch carefully for swimmers

during the engine operation.

8 Stay away from swimming areas.

1-3

8 When a swimmer is in the water near

you shift into neutral and shut off the
engine.

8 Be informed about boating safety. Addi-

tional publications and information can
be obtained from many organizations,
including the following:

United States Coast Guard

Consumer Affairs Staff (G-BC)
Office of Boating, Public, and Consumer
Affairs
U.S. Coast Guard Headquarters
Washington, D.C. 20593-0001
Boating Safety Hotline: [phone]

National Marine Manufacturers

Association (NMMA)

401 N. Michigan Ave.
Chicago, Il 60611

Marine Retailers Association of America

155 N. Michigan Ave.
Chicago, Il 60601

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1-4

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WARNING

This engine is equipped with a neutral starting device.
The engine will not start unless the shift control is
in neutral position.

6E0-83 627-4 1

WARNING

●Be sure shift control is in neutral

before starting engine. (except 2HP)

●Do not touch or remove electrical parts

when starting or during operation.

●Keep hands,hair,and clothes away from flywheel

and other rotating parts while engine is running.

6A1-83 625-4 1

LOCATION

25

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25-3/30

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30

EMB30010

IMPORTANT LABELS

WARNING LABELS

1

202023

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2

202061

q

202062

1-5

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EMB40010

BASIC BOATING RULES

(Rules of the road)

Just as there are rules which apply when
you are driving on streets and high ways,
there are waterway rules which apply
when you are driving your boat. These
rules are used internationally, 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 encounter another vessel
on the water.

Several sets of rules prevail according to
geographic location, but are all basically
the same as the International Rules of the
Road. The rules presented here in your
Owner’s Manual are condensed, and have
been provided for your convenience only.
Consult your local U.S. Coast Guard Aux­iliary or Department of Motor Vehicles for
a complete set of rules governing the
waters in which you will be using your
boat.

STEERING AND SAILING RULES AND
SOUND SIGNALS

Whenever two vessels on the water meet
one another, one vessel has the right-of­way; it is called the “stand-on” vessel.
The vessel which does not have the right­of-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 vessel will be able to
determine how best to avoid you.

Give-way vessel

The vessel which does not have the right­of-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 briefly 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 navigation and collision,
and to any special circumstances,
which may render a departure from
the above rules necessary in order to
avoid immediate danger.’

In other words, follow the standard rules
except when a collision will occur unless
both vessels try to avoid each other. If
that is the case, both vessels become
“Give-Way” vessels.

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RULES WHEN ENCOUNTERING
VESSELS

There are three main situations which you
may encounter with other vessels which
could lead to a collision unless the Steer­ing Rules are followed:

Meeting (you are approaching another
vessel head-on)
Crossing (you are travelling across the
other 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-of­way to any vessels shown in white area
(you are the Give-Way vessel). Any ves­sels in the shaded area must yield to you
(they are the Give-Way vessels). Both you
and the meeting vessel must alter course
to avoid each other.

side. This rule doesn’t apply if both of you
will clear one another if you continue on
your set course and speed.

102044

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 other 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; you
are the Give-Way vessel. If the other ves­sel is on your port (left) side, remember
that you should maintain course and
direction, provided the other vessel gives
you the right-of-way as it should.

102045

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 vessel on your port (left)

102046

Overtaking

If you are passing another vessel, you are
the “Give-Way” vessel. This means that

1-7

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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 another vessel is passing you, you
should maintain your speed and direction
so that the other vessel can steer itself
around you.

OTHER SPECIAL SITUATIONS

There are three other rules you should be
aware of when driving your boat around
other 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 water vessels, the operator
should sound a prolonged 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 proceed
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 which 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 vessels. Fishing ves­sels have the right-of-way regardless of
position. Fishing vessels cannot, 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 power­driven 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 which 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 navigating in a par­ticular direction. The markings on these
buoys are oriented from the perspective
of being entered from seaward (the
boater is going towards the port). This
means that red buoys are passed on the
starboard (right) side when proceeding
from open water into port, and black
buoys are to port (left) side. When navi­gating out of port, your position with
respect to the buoys should be reversed;
red buoys should be to port and 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 distinctive shapes and colors
to show regulatory or advisory informa-

1-8

tion. These markers are white with black

1

11

A

1

11

Proceeding toward head

of navigation from seaward

CAN BUOY

Odd number. Leave to port.

OR

SECONDARY CHANNEL BUOYS

STARTS NEW NUMBERING SYSTEM

old new

C " 1

"

NUN BUOY

Even number. Leave to starboard

N

"

2

"

No change

BUOY

COLOR CODE

BLACK

RED

GREEN

"

A

"

"

2

"

"

1

"

"

3

"

"

4

"

"

5

"

"

7

"

N

"

2

"

"

6

"

C

"

1

"

RB

"

L

"

RG

"

L

"

or

SECONDARY CHANNEL

MAIN CHANNEL

old

new

22

22

22

AA

LL

LL

Odd number. increasing toward head of naviga-

MAIN CHANNEL BUOYS

"

1

" "

3

" "

5

" "

7

"

tion.Leave to port (left) proceeding upstream.

LIGHTED BUOY (Port Hand)`

White Light

Green Light

old

new

old

new

old

new

LIGHTED BUOY (Starboard Hand)`

"

2

" "

4

" "

6

"

Even number,increasing toward head of naviga­tion. Leave to starboard (right) proceeding up­stream.

White Light Red Light

"

A

"

LIGHTED SAFE WATER BUOY

No nu mbe r. Marks midchannel, pass on either
side. Letter has no lat era l signi fic anc e, used for

No n umb er. To pmo st ba nd r ed

-

pr e fe r re d

Top Mark
White Light

White Light

OR

OR

LIGHTED PREFERRED CHANNEL TO

RB

"

L

"

RG

"

L

"

PORT BUOY

identification and location purposes.

channel is to l ef t o f buoy. Letter has no la te ra l
signif icanc e, used for iden tific ation and locat ion
purpos es.

Red Light

Red or
White Light

OR

102052

letters and orange boarders. They signify
speed zones, restricted areas, danger
areas, and general information.
Remember, markings may vary by geo­graphic location. Always consult local
boating authorities before driving your
boat in unfamiliar waters.

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EMU00016

FUELING INSTRUCTIONS

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GASOLINE AND ITS VAPORS ARE HIGH­LY FLAMMABLE AND EXPLOSIVE!
8 Do not smoke when refueling, and

keep away from sparks, flames, or
other sources of ignition.

8 Stop engine before refueling.
8 Refuel in a well-ventilated area. Refuel

portable fuel tanks off the boat.

8 Take care not to spill gasoline. If gaso-

line spills, wipe it up immediately with
dry rags.

8 Do not overfill the fuel tank.
8 Tighten the filler cap securely after

refueling.

8 If you should swallow some gasoline

inhale a lot of gasoline vapor, or get
gasoline in your eyes, get immediate
medical attention.

8 If any gasoline spills onto your skin,

immediately wash with soap and
water. Change clothing if gasoline spills
on it.

8 Touch the fuel nozzle to the filler open-

ing or funnel to help prevent electrosta­tic sparks.

cC

Use only new clean gasoline which has
been stored in clean containers and is not
contaminated with water or foreign mat­ter.

1-10

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EMU00018

GASOLINE (PETROL)

Recommended gasoline:

Regular unleaded gasoline with
a minimum octane rating of 86
(Pump Octane Number) = (R+M)/2

If knocking or pinging occurs, use a differ­ent brand of gasoline or premium unlead­ed fuel. If unleaded gasoline is not avail­able, then leaded regular gasoline can be
used.

EMU00027

Gasohol

There are two types of gasohol: gasohol
containing ethanol and that containing
methanol. Gasohol containing ethanol
can be used if ethanol content does not
exceed 10% and the fuel meets minimum
octane ratings. Gasohol containing
methanol is not recommended by Yama­ha because it can cause fuel system dam­age or engine performance problems.

EMU00858

ENGINE OIL

Recommended engine oil:
YAMALUBE 2 STROKE OUTBOARD
OIL

If the recommended engine oil is not
available, another 2-stroke engine oil with
a NMMA-certified TC-W3 rating may be
used.

1-11

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EMU01430

BATTERY REQUIREMENT

cC

Do not use a battery that does not meet
the specified capacity. If a battery which
differs from the specification is used, the
electrical system may perform poorly or
be overloaded, causing electrical system
damage.

cC

8 A battery cannot be connected to mod-

els which do not have a rectifier or rec­tifier regulator.

Models without a rectifier or rectifier

regulator: 25NMH, 30DMHO, 25JMH

8 If you wish to use a battery with the

above models, install an optional recti­fier regulator.

Models with only a rectifier

installed: 30DEHO

8 Using a maintenance-free battery with

the above models can shorten the life
of the battery significantly.

8 Use caution when connecting acces-

sories such as fish finders, as they may
be damaged by high voltage. Install an
optional rectifier regulator or use acces­sories rated to withstand 18 volts or
higher with the above models. Consult
your Yamaha dealer for details on
installing an optional rectifier regulator.

Choose a battery for electric start models
which meets the following specifications.

Minimum cold crank performance
210 Amps at -17.8°C (0°F)
Minimum reserve capacity
40 minutes at 26.7°C (80°F)

1-12

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EMU01395

PROPELLER SELECTION

The performance of your outboard motor
will be critically affected by your choice of
propeller, as an incorrect choice could
adversely affect performance and could
also seriously damage the motor. Engine
speed depends on the propeller size and
boat load. If engine speed is too high or
too low for good engine performance,
this will have an adverse effect on the
engine.

Yamaha outboard motors are fitted with
propellers chosen to perform well over a
range of applications, but there may be
uses where a propeller with a different
pitch would be more appropriate. For a
greater operating load, a smaller-pitch
propeller is more suitable as it enables
the correct engine speed to be main­tained. Conversely, a larger-pitch pro­peller is more suitable for a smaller oper­ating load.

Yamaha dealers stock a range of pro­pellers, and can advise you and install a
propeller on your outboard that is best
suited to your application.

1-13

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602016

10-3/4x17-F

1 2 3

NOTE:

At full throttle and under a maximum
boat load, the engine’s rpm should be
within the upper half of the full throttle
operating range, as listed in “SPECIFICA­TIONS” on page 4-1. Select a propeller
which fulfills this requirement.
If operating under conditions which allow
the engine’s rpm to rise above the maxi­mum recommended range (such as light
boat loads), reduce the throttle setting to
maintain the rpm in the proper operating
range.

1 Propeller diameter (in inches)
2 Propeller pitch (in inches)
3 Type of propeller (propeller mark)

Refer to the section “CHECKING PRO­PELLER” for instructions on propeller
removal and installation.

EMU01209

START-IN-GEAR PROTECTION

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

1-14

-MEMO-

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EMC00010

Chapter 2

BASIC COMPONENTS

MAIN COMPONENTS..............................2-1

OPERATIONS OF CONTROLS AND

OTHER FUNCTIONS ................................2-3

Fuel tank ................................................2-3

Gear shift lever .....................................2-3

Engine stop lanyard switch .................2-4

Engine stop button...............................2-5

Tiller handle ..........................................2-5

Choke knob ...........................................2-6

Recoil starter handle ............................2-6

Starter button........................................2-7

Remote control .....................................2-7

Steering friction adjusting screw......2-10

Trim tab ...............................................2-11

Trim angle adjusting rod ...................2-11

Shallow water lever ...........................2-12

Tilt lock mechanism ...........................2-12

Tilt support bar ...................................2-13

Tilt support lever ................................2-13

Top cowling lock lever.......................2-13

WARNING SYSTEM ..............................2-14

Overheat warning...............................2-14

Oil level warning / oil filter clogging

warning ...............................................2-15

1

2

3

4

5

6

EMU01206

101061

!1

!0

!6

!2

!4 u

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!3

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!5

25

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MAIN COMPONENTS

1 Recoil starter handle
2 Choke knob
3 Warning lamp
4 Gear shift lever
5 Throttle-control grip/Tiller-handle
6 Engine stop button/

Engine stop lanyard switch

7 Transom-clamp handle
8 Tilt lock lever
9 Cooling water inlet
0 Propeller
q Trim tab (Anode)
w Anti-cavitation plate

e Trim angle adjusting-rod
r Rope attachment
t Shallow water lever
y Fuel tank

* May not be exactly as shown; also may

not be included as standard equipment on
all models.

2-1

EMU01206

701061

101113**

t
y

u

r

w

e

101111

q

i

!0
o

!2

!8

!4

!5

!6

!7

@0

!3

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!1

!9

@1

25-3/30

MAIN COMPONENTS

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1 Top cowling
2 Tilt-lock lever
3 Transom-clamp handle
4 Anti-cavitation plate
5 Trim tab
6 Cooling water inlet
7 Propeller

* 8 Battery lead

9 Trim angle adjusting rod
0 Clamp bracket
q Wiring harness

* w Recoil starter handle

e Engine stop button/Engine stop lanyard

switch

r Warning lamp
* t Gear shift lever
* y Throttle-control grip/tiller handle
* u Shallow water lever
* i Rope attachment
* o Choke knob
* p Remote control box
* a Fuel tank

* May not be exactly as shown; also may not

be included as standard equipment on all
models.

2-2

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qwe

r

902051

EMC20010

OPERATIONS OF CONTROLS

AND OTHER FUNCTIONS

EMC21012

FUEL TANK

If your model was equipped with a
portable fuel tank, its function is as fol­lows.

1 Fuel hose joint
2 Fuel meter(If equipped)
3 Fuel tank cap
4 Air vent screw(If equipped)

Fuel hose joint

This connector is provided for connecting
or disconnecting fuel hose.

Fuel meter

This meter is on the fuel tank cap. It
shows current fuel quantity in the fuel
tank approximately.

e

q

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406015

Fuel tank cap

This cap is for filling fuel. To remove it,
turn it counterclockwise.

Air Vent screw

This screw is on the fuel tank cap. To
loosen it, turn it counterclockwise.

EMC25010

GEAR SHIFT LEVER (for Tiller control
model)

Turning the gear-shift lever towards you
engages the clutch with the forward gear
so that the boat moves ahead. Turning
the lever away from you engages the
reverse gear so that the boat moves
astern.

1 Neutral
2 Forward
3 Reverse

2-3

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1

2

001127

25

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001126

EMC28111

ENGINE STOP LANYARD SWITCH
(for Tiller control model)

The lock-plate on the end of the lanyard
must be attached to the engine stop
switch for the engine to run. The lanyard
should be attached to a secure place on
the operator’s clothing, or arm or leg.
Should the operator fall overboard or
leave the helm, the lanyard will pull out
the lock plate, stopping ignition to the
engine. This will prevent the boat from
running away under power.

1 Lock-plate
2 Lanyard

w

8 Attach the engine stop switch lanyard

to a secure place on your clothing, your

arm or leg while operating.

8 Do not attach the lanyard to clothing

that could tear loose. Do not route the

lanyard in such a way that it could

become entangled, preventing it from

functioning.

8 Avoid accidentally pulling the lanyard

during normal operation. Loss of

engine power means the loss of most

steering control. Also, without engine

power, the boat could slow rapidly.

This could cause people and objects in

the boat to be thrown forward.

NOTE:

The engine cannot be started with the
lock-plate removed.

2-4

E

503022**

q

3

25 25-3/30

w

e

q

503021*

EMC27011

ENGINE STOP BUTTON
(for Tiller control model)

Pushing this button opens the ignition cir­cuit and stops the engine.

EMU00062

TILLER HANDLE (for Tiller control
model)

Moving the tiller handle sideways to
adjust the steering direction. In addition,
this handle contains the functions as fol­lows.

1 Throttle control grip
2 Throttle indicator
3 Throttle friction adjusting knob/screw

EMU00065

Throttle Control Grip

The throttle control grip is on the tiller
handle. Turn the grip counterclockwise to
increase speed and clockwise to decrease
speed.

503032

EMU00067

Throttle Indicator

The fuel consumption curve on the throt­tle indicator shows the relative amount of
fuel consumed for each throttle position.
Choose the setting that offers the best
performance and fuel economy for the
desired operation.

1 Throttle indicator

2-5

502011

209015

25 25-3/30

305022*

EMU01293

Throttle friction adjusting screw/ knob

A friction device in the tiller handle pro­vide resistance to movement of the throt­tle grip.
This is adjustable for operator preference.
An adjusting screw/knob is located within
the tiller handle.

Resistance Knob/Screw
Increase Turn clockwise
Decrease Turn counterclockwise

When constant speed is desired, tighten
the adjusting screw/bolt to maintain the
desired throttle setting.

w

Do not over tighten the friction adjusting
screw/ knob.
If there is too much resistance, it may be
difficult to move the throttle grip, which
could result in an accident.

EMC42010

CHOKE KNOB

Pulling out this knob (setting it to ON)
supplies a rich mixture required to start
the engine.

305023*

E

NOTE:

The choke knob for Remote control model
has the same function as the choke switch
on the remote control box.

EMC44010

RECOIL STARTER HANDLE
(If equipped)

Pull the handle gently until resistance is
felt. Then vigorously pull the handle
straight out to crank the engine to start it.

2-6

E

306014

000893

w

q

e

r
t

y

R

N

F

q

w

e

r

t

y

u

u

t

r

y

30

EMC46010

STARTER BUTTON (for Tiller control
model)

When you push the starter button, the
electric starter motor cranks the engine to
start it.

EMU00090

REMOTE CONTROL

Both the shifter and the throttle are actu­ated by the remote control lever. In addi­tion, this remote control also has the elec­trical switches.

1 Remote control lever
2 Neutral interlock trigger
3 Neutral throttle lever
4 Main switch / Choke switch
5 Engine stop lanyard switch
6 Throttle friction adjusting screw

Remote control lever

Moving the lever forward from the Neu­tral position engages Forward gear.
Pulling the lever back from Neutral
engages Reverse. The engine will contin­ue to run at idle until the lever is moved
about 35° (a detent can be felt). Moving
the lever farther opens the throttle, and
the engine will begin to accelerate.

1 Neutral
2 Forward
3 Reverse
4 Shift
5 Fully closed
6 Throttle
7 Fully open

2-7

E

701036

ON

STARTOFF

701021

Neutral interlock trigger

To shift out of Neutral, the neutral inter­lock trigger of the remote control lever
must first be pulled up.

Neutral throttle lever

N

q

w

701033*

To open the throttle without shifting into
either Forward or Reverse, place the
remote control lever in the Neutral posi­tion and lift the neutral throttle lever.

NOTE:

The neutral throttle lever will operate only
when the remote control lever is in Neu­tral. The remote control lever will operate
only when the neutral throttle lever is in
the closed position.

1 Fully open
2 Fully closed

EMC48110

Main switch

The main switch controls the ignition sys­tem; its operation is described below.

8 OFF

Electrical circuits switched off.
(The key can be removed.)

8 ON

Electrical circuits switched on.
(The key cannot be removed.)

8 START

Starter-motor will turn and start engine.
(When the key is released, it returns auto­matically to “ON”.)

2-8

STARTOFF

ON

701042

000569

q

w

E

EMC50310

Choke switch

While the main switch is being pressed in
at “ON” or “START”, the choke system
will switch on, to supply a rich mixture
required to start the engine. (When the key
is released, it will switch off automatically.)

EMU00934

Engine Stop Lanyard Switch

The lock-plate 1 must be attached to the
engine stop lanyard switch for the engine
to run. The lanyard 2 should be attached
to a secure place on the operator’s cloth­ing, or arm or leg. Should the operator fall
overboard or leave the helm, the lanyard
will pull out the lock plate, stopping igni­tion to the engine. This will prevent the
boat from running away under power.

w

8 Attach the lanyard to a secure place on

your clothing, your arm or leg while

operating.

8 Do not attach the lanyard to clothing

that could tear loose. Do not route the

lanyard in such a way that it could

become entangled, preventing it from

functioning.

8 Avoid accidentally pulling the lanyard

during normal operation. Loss of

engine power means the loss of most

steering control. Also, without engine

power, the boat could slow rapidly.

This could cause people and objects in

the boat to be thrown forward.

NOTE:

The engine cannot be started with the
lock-plate removed.

2-9

701035

408015

E

EMU01155

Throttle Friction Adjusting Screw

A friction device in the remote control box
provides adjustable resistance to move­ment of the remote control lever, and can
be set according to operator preference.
An adjusting screw is located on the front
of the remote control box.

Resistance Screw
Increase Turn clockwise
Decrease Turn counterclockwise

w

Do not overtighten the friction adjusting
screw. If there is too much resistance, it
may be difficult to move the lever, which
could result in an accident.

EMD00011

STEERING FRICTION ADJUSTING
SCREW(for Tiller control model)

A friction device provides resistance to
steering movement. This is adjustable for
operator preference. An adjusting
screw/bolt is located on the swivel brack­et.

EMD00310*

Adjustment

Resistance Screw/bolt
Increased Turn clockwise
Decreased Turn counterclockwise

w

Do not overtighten the friction
screw/bolt.
If there is too much resistance, it may be
difficult to steer, which could result in an
accident.

2-10

E

603011

w

q

A B

404015

EMU00113

TRIM TAB

The trim tab should be adjusted so that
the steering control can be turned to
either the right or left by applying the
same amount of force.

w

An improperly adjusted trim tab may
cause difficult steering. Always test run
after the trim tab has been installed or
replaced to be sure steering is correct. Be
sure you have tightened the bolt after
adjusting the trim tab.

1 Trim tab
2 Bolt
3 Cap (If equipped)

25

404022*

25-3/30

Boat tends
to veer

The fin of trim tab

To the left Turn to the left
(port side) (A in the figure)

To the right
(starboard
side)

Turn to the right
(B in the figure)

cC

The trim tab also serves as an anode to
protect the engine from electrochemical
corrosion. Never paint the trim tab as it
will become ineffective as an anode.

EMU01297

TRIM ANGLE ADJUSTING ROD

The position of the trim angle adjusting
rod determines the minimum trim angle
of the outboard motor in relation to the
transom.

2-11

E

402075*

402072*

402035*

q

25

25-3/30

25

q

402061*

EMD08010

SHALLOW WATER LEVER
(If equipped)

25

Lifting this lever will tilt the motor up par­tially to provide more clearance when
operating in shallow water.

EMD08110

SHALLOW WATER LEVER
(If equipped)

25-3/30

Pushing this lever down will tilt the motor
up partially to provide more clearance
when operating in shallow water.

EMD44010

TILT LOCK MECHANISM
(for Manual tilt model)

The tilt-lock mechanism is used to pre­vent reverse thrust from the propeller lift­ing the outboard motor when reversing.
To lock it, set the tilt-lock lever in the up
position. To release it, push the tilt-lock
lever down.

25-3/30

1 Tilt-lock lever

2-12

E

403023

q

25

25-3/30

EMU00156

TILT SUPPORT BAR

25

The tilt support bar 1 keeps the outboard
motor in the tilted up position.

EMD60210

TILT SUPPORT LEVER

25-3/30

To keep the outboard motor in the tilted­up position, lock the tilt support lever to
the swivel bracket.

403024

EMD62010

TOP COWLING LOCK LEVER

To remove the engine top cowling, push
the lock lever downward. Then lift off the
cowling. When replacing the cowling,
check to be sure it fits properly in the rub­ber seal. Then lock the cowling again by
moving the lever upward.

2-13

E

EMD80010

WARNING SYSTEM

cC

Do not continue to operate the engine if
the warning device has activated. Consult
your Yamaha dealer if the problem can­not be located and corrected.

25

25-3/30

303013

303014

EMU00170

OVERHEAT WARNING

This engine has an overheat warning
device. If the engine temperature rises too
high, the warning device will activate.

(

2); Included (—); N/A

Activation of
warning device

The engine speed
will automatically
decrease to about
2,000 r/min.

The overheat warning
indicator will come on.

The buzzer will sound.

If the warning system has been activated,
stop the engine and check the water inlet
for clogging.

Tiller Remote
control control
model model

2 2

2 2

— 2

2-14

213023

q

30

303014

E

EMU00172

OIL LEVEL WARNING / OIL FILTER
CLOGGING WARNING

This engine has an oil level warning sys­tem. If oil level falls below lower limit, the
warning device will activate.

(

2); Included (—); N/A

Warning device
activation

The engine speed
will automatically
decrease to about
2,000 r/min.

The oil level warning
indicator will come on.

The buzzer will sound.

If the warning system has been activated,
stop the engine and check for the cause.

NOTE:

The warning for oil filter clogging is simi­lar to the warnings for low oil level and
overheating. For easy troubleshooting, it
is advisable to check for engine overheat­ing first, then oil level and finally oil filter
clogging.

Tiller Remote
control control
model model

2 2

2 2

— 2

1 Oil filter

2-15

Oil level warning system
30

The various oil-level warning system functions are as follows:

E

Oil level warning indicator lamp

(Bottom cowling)

OFF

Red ON

0.181 Imp qt)

3

or less (0.21 US qt, 0.181

200 cm
Imp qt)

3

(0.21 US qt,

RemarksEngine oil tank

No refilling necessary.more than 200 cm

Buzzer sounds in remote control
box and engine speed is limited
to about 2,000 r/min to help
conserve oil.
Check oil filter for clogging.
Add oil.

2-16

-MEMO-

E

E

EMF00010

Chapter 3

OPERATION

INSTALLATION ........................................3-1

Mounting the outboard motor............3-2

Clamping the outboard motor.....3-4, 3-5

FILLING FUEL AND ENGINE OIL ............3-6

Filling fuel..............................................3-6

Filling oil ................................................3-7

Gasoline (petrol) and oil mixing .........3-9

PRE-OPERATION CHECKS....................3-11

Operation after a long period of

storage.................................................3-12

BREAKING IN (RUNNING IN)

ENGINE ...................................................3-13

1

2

3

STARTING ENGINE ...............................3-15

WARMING UP ENGINE .........................3-22

SHIFTING ................................................3-23

Forward ...............................................3-23

Reverse................................................3-24

STOPPING ENGINE ...............................3-25

TRIMMING OUTBOARD MOTOR.........3-26

Adjusting trim angle ..........................3-27

CRUISING IN SHALLOW WATER.........3-29

TILTING UP/DOWN ...............................3-31

CRUISING IN OTHER CONDITIONS.....3-34

Cruising in salt water .........................3-34

Cruising in turbid water.....................3-34

4

5

6

E

EMF10010

INSTALLATION

cC

Incorrect engine height or obstructions to
smooth water flow (such as the design or
condition of the boat or accessories such
as transom ladders/depth finder trans­ducers) can create airborne water spray
while the boat is cruising. Severe engine
damage may result if the motor is operat­ed continuously in the presence of air­borne water spray.

NOTE:

During water testing check the buoyancy
of the boat, at rest, with its maximum
load. Check that the static water level on
the exhaust housing is low enough to pre­vent water entry into the powerhead,
when water rises due to waves when the
outboard is not running.

3-1

E

104011

q

EMU00176

MOUNTING THE OUTBOARD
MOTOR

w

Improper mounting of the outboard
motor could result in hazardous condi­tions such as poor handling, loss of con­trol, or fire hazards. Observe the follow­ing:
8 The information presented in this sec-

tion is intended as reference only. It is
not possible to provide complete
instructions for every possible
boat/motor combination. Proper
mounting depends in part on experi­ence and the specific boat/motor com­bination.

8 Your dealer or other person experi-

enced in proper rigging should mount
the motor. If you are mounting the
motor yourself, you should be trained
by an experienced person. [permanent
mounted type]

8 Your dealer or other person experi-

enced in proper outboard motor
mounting should show you how to
mount your motor. [portable type]

Mount the outboard motor on the center
line (keel line) of the boat, and ensure that
the boat itself is well balanced. Otherwise,
the boat will be hard to steer. For boats
without a keel or which are asymmetrical,
consult your dealer.

1 Center line (keel line)

3-2

E

104013

0~25mm

w

Overpowering a boat may cause severe
instability. Do not install an outboard
motor with more horsepower than the
maximum rating on the capacity plate of
the boat. If the boat does not have a
capacity plate, consult the boat manufac­turer.

EMU01298

Mounting Height

To run your boat at optimum efficiency,
the water-resistance (drag) of the boat
and outboard motor must be made as lit­tle as possible. The mounting-height of
the outboard motor greatly affects the
water-resistance. If the mounting-height
is too high, cavitation tends to occur, thus
reducing the propulsion; and if the pro­peller tips cut the air, the engine speed
will rise abnormally and cause the engine
to overheat. If the mounting-height is too
low, the water-resistance will increase
and thereby reduce engine efficiency.
Mount the engine so that the anti-cavita­tion plate is between the bottom of the
boat and a level 25 mm (1 in.) below it.

NOTE:

8 The optimum mounting height of the

outboard motor is affected by the
boat/motor combination and the
desired use. Test runs at different
heights can help determine the opti­mum mounting height.

8 Refer to the section “TRIMMING OUT-

BOARD MOTOR” for instructions on
setting the trim angle of the outboard.

3-3

E

409011

EMF14010

CLAMPING THE OUTBOARD MOTOR

1) Place the outboard on the transom so
that it is positioned as close to the
center as possible. Tighten the tran­som clamp screws evenly and secure­ly. Check the clamp-screws for tight­ness occasionally during operation of
the motor as they can work loose due
to engine vibration.

w

Loose clamp screws could allow the
motor to move on the transom or fall off
the transom. This could cause loss of
control and serious injury. Make sure the
transom screws are tightened securely.
Occasionally check the screws for tight­ness during operation.

2) An engine restraint cable or chain
should be used. Attach one end to
the engine restraint cable attachment
point and the other to a secure
mounting point on the boat. Other­wise, the engine could be completely
lost if it accidentally falls off the tran­som.

410012

3-4

409011

q

410012

409012

E

EMU01318

CLAMPING THE OUTBOARD MOTOR

30EH/30ER

1) Place the outboard on the transom so

that it is positioned as close to the
center as possible. Tighten the tran­som clamp screws evenly and secure­ly. Check the clamp-screws for tight­ness occasionally during operation of
the motor as they can work loose due
to engine vibration.

w

Loose clamp screws could allow the
motor to move on the transom or fall off
the transom. This could cause loss of
control and serious injury. Make sure the
transom screws are tightened securely.
Occasionally check the screws for tight­ness during operation.

2) An engine restraint cable or chain

should be used. Attach one end to
the engine restraint cable attachment
point and the other to a secure
mounting point on the boat. Other­wise, the engine could be completely
lost if it accidentally falls off the tran­som.
Secure the clamp bracket to the tran­som with the bolts provided with the
outboard. For details, consult your
dealer.

w

Avoid using bolts, nuts or washers other
than those contained in the engine pack­aging. If used, they must be of at least
the same quality of material and strength
and must be tightened securely. After
tightening, test run the engine and check
their tightness.

1 Motor mounting parts

3-5

E

902055

EMF30010

FILLING FUEL AND

ENGINE OIL

FILLING FUEL

1) Remove the fuel tank cap.

2) Fill the fuel tank carefully.

3) Close the cap securely after refueling.
Wipe up any spilled fuel.

Fuel tank capacity:

Refer to SPECIFICATIONS on Page 4-1.

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 concerns about pollution and
resulting emissions regulations. One of
the most obvious changes has been the
elimination of lead from most fuels.

As gasoline has changed, the amount of
additives such as aromatics and oxy­genates has increased. These additives
are important for the engines in passen­ger cars, but they can have detrimental
effects in marine engines, particularly 2­cycle outboards because of increased
deposits in the combustion chamber.
When enough deposits collect, piston
rings begin sticking. Performance drops
and engine wear increases dramatically.

3-6

E

While many additives available may
reduce deposits, Yamaha recommends
the use of Ring Free Fuel Additive, avail­able from your Yamaha dealer. Ring Free
has repeatedly proven its ability to clean
combustion deposits from inside the
engine, notably the critical piston-ring­land area, and fuel system components.
Follow product labeling for use instruc­tions

EMF32110

FILLING OIL (for Precision blend
system model)

This engine uses the YAMAHA PRECI­SION BLEND SYSTEM, which provides
superior lubrication by ensuring the prop­er oil ratio for all operating conditions. No
fuel premixing is needed (except during
break-in/running-in). Simply pour gaso­line into the fuel tank and oil into the oil
tank.

Convenient indicator segments indicate
condition of the oil supply. Refer to oil
warning system.
To fill the engine oil into the engine oil
tank, proceed as follows:

w

Do not add gasoline (Petrol) into the oil
tank. Fire or explosion could result.

Engine oil tank capacity:

Refer to “SPECIFICATION”, page 4-1.

3-7

E

203012*

q

w

30MH

30EH/30ER

w

q

Manual start model

1) Remove the top cowling.

2) Open the oil tank filler cap by pulling
the tab.

3) Slowly fill the engine oil into the
engine oil tank.

4) After filling, replace the cap securely.

5) Replace the top cowling securely.

1 Engine oil tank
2 Oil tank filler cap

Electric start model

1) Turn the oil filler access cap on top of
the top cowling counterclockwise and
open it.

2) Open the oil tank filler cap by pulling
a tab on the cap.

3) Slowly fill the engine oil into the
engine oil tank.

4) After filling, replace the all caps
securely.

1 Oil filler access cap
2 Oil tank filler cap

203022

3-8

q

E

EMF35011

GASOLINE (PETROL) AND OIL
MIXING

Pre-mix model

Engine oil : Gasoline (Petrol)

Break-in period 1 : 25

After break-in 1 : 100

w

1) Pour oil and gasoline into the fuel

tank, in that order.

1 Engione oil
2 Gasoline (Petrol)

2) Then mix the fuel thoroughly by shak-

ing.

3) Make sure the oil is mixed with gaso-

line .

902033

cC

8 Avoid using any oil other than the des-

ignated type.

8 Use a thoroughly blended fuel-oil mix-

ture.

8 If the mixture is not thoroughly blend-

ed, or if the mixing ratio is incorrect,
the following problems could occur:
Low oil ratio: Lack of oil could cause
major engine trouble, such as piston
seizure.
High oil ratio: Too much oil could cause
fouled spark plugs, smoky exhaust, and
heavy carbon deposits.

3-9

E

Mixing ratio

25 : 1

Gasoline (Petrol)

Engine oil

(0.26 US gal,

0.22 Imp gal)

(0.04 US qt, (0.51 US qt, (0.59 US qt, (1.01 US qt,

0.04 Imp qt) 0.42 Imp qt) 0.49 Imp qt) 0.84 Imp qt)

(3.2 US gal, (3.7 US gal, (6.3 US gal,

2.6 Imp gal) 3.1 Imp gal) 5.3 Imp gal)

0.04 L 0.48 L 0.56 L 0.96 L

1 L 12 L 14 L 24 L

Mixing ratio

100 : 1

Gasoline (Petrol)

Engine oil

(0.26 US gal,

0.22 Imp gal)

(0.01 US qt, (0.13 US qt, (0.15 US qt, (0.25 US qt,

0.01 Imp qt) 0.11 Imp qt) 0.12 Imp qt) 0.21 Imp qt)

(3.2 US gal, (3.7 US gal, (6.3 US gal,

2.6 Imp gal) 3.1 Imp gal) 5.3 Imp gal)

0.01 L 0.12 L 0.14 L 0.24 L

1 L 12 L 14 L 24 L

NOTE:

If using a permanently installed tank, pour
the oil gradually as the fuel is being
added to the tank.

3-10

MU00204

PRE-OPERATION CHECKS

w

If any item in the pre-operation check is
not working properly, have it inspected
and repaired before operating the out­board motor. Otherwise, an accident
could occur.

cC

Do not start the engine out of water.
Overheating and serious engine damage
can occur.

EMU00206

Fuel

8 Check to be sure you have plenty of fuel

for your trip.

8 Make sure there are no fuel leaks or

gasoline fumes.

8 Check fuel line connections to be sure

they are tight.

8 Be sure the fuel tank is positioned on a

secure, flat surface, and that the fuel
hose is not twisted or flattened, or likely
to contact sharp objects.

EMU00207

Oil

8 Check to be sure you have plenty of oil

for your trip.

EMU00209

Controls

8 Check throttle, shift, and steering for

proper operation before starting the
engine.

8 The controls should work smoothly,

without binding or unusual free play.

8 Look for loose or damaged connec-

tions.

8 Check operation of the starter and stop

switches when the outboard motor is in
the water.

3-11

E

203024

OIL

30

E

EMU00210

Engine

8 Check the engine and engine mounting.
8 Look for loose or damaged fasteners.
8 Check the propeller for damage.

EMF44010

OPERATION AFTER A LONG PERIOD
OF STORAGE (for Precision blend
system model)

When operating the engine after a long
period (12 months) of storage, proceed as
follows:

1) Use a 50 : 1 gasoline-oil mixture to
start the engine.

2) Start the engine. Leave it idling.

w

8 Do not touch or remove electrical parts

when starting or during operation.

8 Keep hands, hair, and clothes away

from flywheel and other rotating parts
while engine is running.

30

3) Watch for oil flowing through the oil
feed pipes. After any air in the oil
lines has been expelled, YAMAHA
PRECISION BLEND SYSTEM should
supply oil normally. If no oil has
begun flowing after 10 minutes of
idling, consult your Yamaha dealer.

cC

When operating the engine after a long
period of storage, be sure to take the
above steps; otherwise, engine seizure
may occur.

3-12

E

EMF50211

BREAKING IN (RUNNING IN)

ENGINE

Your new engine requires a period of
break-in (running-in) to allow mating sur­faces of moving parts to wear-in evenly.
Correct break-in (running-in) will help
ensure proper performance and longer
engine life.

cC

8 Failure to follow the break-in (running-

in) procedure may result in reduced
engine life or even severe engine dam­age.

8 Premix fuel must be used during break-

in (running-in) in addition to oil in the
Precision Blend System.

Break-in (running-in) time:

10 hours

Break-in (running-in) premix ratio (for
Pre-mix model):

Gasoline (Petrol) : Engine oil=25 : 1
Refer to “Gasoline/Petrol and Oil
Mixing”.

Break-in (running-in) premix ratio (for
Precision Blend System model)

Gasoline (Petrol) : Engine oil=50 : 1

Mixing ratio

Gasoline (Petrol)

Engine oil

1 L 12 L 14 L 24 L

(0.26 US gal,

0.22 Imp gal

0.02 L 0.24 L 0.28 L 0.48 L

(0.02 US qt, (0.25 US qt, (0.30 US qt, (0.51 US qt,

0.02 Imp qt) 0.21 Imp qt) 0.25 Imp qt) 0.42 Imp qt)

50 : 1

(3.2 US gal, (3.7 US gal, (6.3 US gal,

) 2.6 Imp gal) 3.1 Imp gal) 5.3 Imp gal)

3-13

E

cC

Make sure to mix gasoline (petrol) and oil
completely, otherwise your outboard
motor may be damaged.

EMU00229

Run the engine under load (in gear with a
propeller installed) as follows.

1) First 10 minutes:
Run the engine at the lowest possi­ble-speed. A fast idle in neutral is
best.

2) Next 50 minutes:
Do not exceed half throttle (approxi­mately 3,000 r/min). Vary engine
speed occasionally. If you have an
easy-planing boat, accelerate at full
throttle onto plane, then immediately
reduce the throttle to 3,000 r/min or
less.

3) Second hour:
Accelerate at full throttle onto plane,
then reduce engine speed to three­quarter throttle (approximately 4,000
r/min). Vary engine speed occasional­ly. Run at full throttle for one minute,
then allow about 10 minutes of opera­tion at three-quarter throttle or less to
let the engine cool.

4) Third through tenth hours:
Avoid operating at full throttle for
more than 5 minutes at a time. Let the
engine cool between full-throttle runs.
Vary engine speed occasionally.

Pre-mix model

5) After the first 10 hours:
Operate the engine normally. Use the
standard premix ratio of gasoline
(petrol) : Oil.
(Refer to “Gasoline/Petrol and Oil
Mixing”.)

3-14

E

Precision Blend System model

5) After the first 10 hours:

Operate the engine normally. Use
straight gasoline (petrol) in the fuel
tank; YAMAHA PRECISION BLEND
SYSTEM provides proper lubrication
for normal operation.

EMU01147

STARTING ENGINE

w

8 Before starting the engine, make sure

that the boat is tightly moored and that
you can steer clear of any obstructions.
Be sure there are no swimmers in the
water near you.

8 When the air vent screw is loosened,

gasoline (petrol) vapor will be released.
Gasoline (petrol) is highly flammable,
and its vapors are flammable and
explosive. Refrain from smoking, and
keep away from open flames and
sparks while loosening the air vent
screw.

8 This product emits exhaust gases

which contain carbon monoxide, a col­orless, odorless gas which may cause
brain damage or death when inhaled.
Symptoms include nausea, dizziness,
and drowsiness. Keep cockpit and
cabin areas well ventilated. Avoid
blocking exhaust outlets.

3-15

E

902053

304024*

N

406012

1) If there is an air vent screw on the fuel
tank cap, loosen it 2 or 3 turns.

25

902061

25-3/30

2) If there is a fuel joint on the motor,
firmly connect the fuel line to the
joint. Then firmly connect the other
end of the fuel line to the joint on the
fuel tank.

NOTE:

During engine operation place the tank
horizontally, or fuel cannot be drawn into
the engine.

3) Squeeze the primer bulb with the out­let end up until you feel it become
firm.

902025

EMU00854

PROCEDURE FOR TILLER CONTROL
MODEL

4) Place the gear-shift lever in the neu­tral position.

NOTE:

The start-in-gear protection device pre­vents the engine from starting except
when in Neutral.

3-16

E

407016

503022

305022*

5) Place the throttle control grip in the

“START” position.

25

25-3/30

25 25-3/30

308013*

6) Attach the engine stop switch lanyard

to a secure place on your clothing, or
your arm or leg. Then, install the lock
plate on the other end of the lanyard
in the engine stop switch.

w

8 Attach the engine stop switch lanyard

to a secure place on your clothing, your
arm or leg while operating.

8 Do not attach the lanyard to clothing

that could tear loose. Do not route the
lanyard where it could become entan­gled, preventing it from functioning.

8 Avoid accidentally pulling the lanyard

during normal operation. Loss of
engine power means the loss of most
steering control. Also, without engine
power, the boat could slow rapidly.
This could cause people and objects in
the boat to be thrown forward.

EMU00240

Manual Start Model

7) Pull out the choke knob completely.

After the engine starts, return the
knob to the original position.

NOTE:

8 It is not necessary to use the choke

305023*

when restarting a warm engine.

8 If the choke knob is left pulled out after

the engine starts, the engine will stall.

3-17

209015

503012

306014

E

8) Pull the starter handle slowly until
you feel resistance. Then, give a
strong pull straight out to crank and
start the engine. Repeat it, if neces­sary.

9) After the engine starts, return the
starter handle slowly to the original
position before releasing it.

10) Return the throttle to the fully closed
position.

30EH/30ER

30EH/30ER

305023*

EMU00242

Electric Start Model

7) Pull out the choke knob completely.
After the engine starts, return the
choke knob to the original position.

NOTE:

8 It is not necessary to use the choke

when restarting a warm engine.

8 If the choke knob is left pulled out, the

engine will stall.

8) Push the starter-button to start the
starting motor.

9) Immediately the engine starts, release
the starter-button to return it to the
original position.

3-18

N

503012

E

10) Return the throttle control grip slowly

to the fully closed position so that the
engine does not stall.

cC

8 Never push the starter-switch while the

engine is running.

8 Do not keep the starter motor turning

for more than 5 seconds. If the starter­motor is turned continuously for more
than 5 seconds, the battery will be
quickly discharged, thus making it
impossible to start the engine. If the
engine will not start after 5 seconds of
cranking, release your hand from the
starter-switch, and crank the engine
again after an interval of 10 seconds.

EMU00247

PROCEDURE FOR REMOTE
CONTROL MODEL

4) Place the remote control lever in the

Neutral position.

NOTE:

The start-in-gear protection device pre­vents the engine from starting except
when in Neutral.

5) Attach the engine stop switch lanyard

to a secure place on your clothing, or
your arm or leg. Then, install the lock
plate on the other end of the lanyard
in the engine stop switch.

000293

3-19

E

701013*

N

w

8 Attach the engine stop switch lanyard

to a secure place on your clothing, your
arm or leg while operating.

8 Do not attach the lanyard to clothing

that could tear loose. Do not route the
lanyard where it could become entan­gled, preventing from functioning.

8 Avoid accidentally pulling the lanyard

during normal operation. Loss of
engine power means the loss of most
steering control. Also, without engine
power, the boat could slow rapidly.
This could cause people and objects in
the boat to be thrown forward.

6) Turn the main switch to “ON”.

MU00945

Electric Start Model

7) Open the throttle slightly lifting the
neutral throttle lever upwards partial­ly. You may need to change the throt­tle opening slightly depending on
engine temperature.
After the engine starts, return the
throttle to the original position.

NOTE:

8 As a starting point, lift the lever just

until you feel resistance, then lift slight­ly more.

8 The operation of the neutral throttle

lever is possible only when the remote
control lever is in “N”.

3-20

E

STARTOFF

ON

701041

8) Press in and hold the main switch to

operate the remote choke system.

ON

STARTOFF

(The remote choke switch returns to
its home position when you release
your hand. Therefore, keep the switch
pressed in.)

NOTE:

8 It is not necessary to use the choke

701042

when the engine is warm.

8 Set the choke knob to the home posi-

tion, or the remote choke system will
not operate.

9) Turn the main switch to “START”,

and hold it for a maximum of 5 sec­onds.

10) Immediately after the engine starts,

release the main switch to return it to
“ON”.

cC

8 Do not turn the main switch to

“START” when the engine is running.

8 Do not keep the starter-motor turning

for more than 5 seconds. The battery
will rapidly become exhausted and it
will be impossible for it to start the
engine. If the engine does not start
within 5 seconds, return the main
switch to “ON”, wait 10 seconds, and
then crank the engine again.

3-21

E

309012

EEMG00010

WARMING UP ENGINE

1) Before beginning operation, allow the
engine to warm up at idling speed for
3 minutes. (Failure to do this will
shorten engine life.)

2) Check for a steady flow of water from
the cooling-water pilot hole.

cC

A continuous flow of water from the pilot
hole shows that the water pump is
pumping water through the cooling pas­sages. If water is not flowing out of the
pilot hole at all times while the engine is
running, do not continue to run the
engine. Overheating and serious damage
could occur. Stop the engine and check
to see if the water inlet on the lower cas­ing is blocked. If the problem cannot be
found and corrected, consult your Yama­ha dealer.

3-22

406013

N

F

701043

N

F

503012

E

MG20710

SHIFTING

w

Before shifting, make sure there are no
swimmers or obstacles in the water near
you.

cC

To change the shifting position from for­ward to reverse or vice-versa, close the
throttle first so that the engine idles (or
runs at low speeds).

FORWARD

Tiller control model

1) Place the throttle control grip in the

fully closed position.

2) Turn the gear-shift lever quickly and

firmly from Neutral to Forward.

Remote control model

Pull up the neutral interlock trigger and
move the remote control lever quickly
and firmly from Neutral to Forward.

3-23

25 25-3/30

503012

E

EMU01326

REVERSE

w

When operating in Reverse, go slowly. Do
not open the throttle more than half. Oth­erwise, the boat may become unstable,
which could result in loss of control and
an accident.

1) Place the throttle control grip in the
fully closed position (for Tiller control
model).

2) Check that the tilt-lock lever (for Man­ual tilt/Hydro-tilt model) is in the
locked position.

402062*

R

N

402051*

Tiller control model

3) Turn the gear-shift lever quickly and
firmly from Neutral to Reverse.

406014

Remote control model

N

R

3) Pull up the neutral interlock trigger if
equipped and move the remote con­trol lever quickly and firmly from Neu­tral to Reverse.

701044

3-24

E

407016*

ON

START

OFF

701023

25

25-3/30

308013

EEMG38010

STOPPING ENGINE

Let it cool off for a few minutes at idle or
low speed first. Stopping the engine
immediately after operating at high speed
is not recommended.

EMU00277

1) Push and hold the engine stop button

or turn the main switch to “OFF”.

2) If the fuel joints are provided, discon-

nect the fuel line from the motor after
stopping the engine.

3) Tighten the air vent screw on the fuel

tank cap after stopping the engine, if
it is equipped.

4) Remove the key if the boat will be left

unattended.

NOTE:

The engine can also be stopped by
pulling the lanyard and removing the lock
plate from the engine stop lanyard switch
(then turning the main switch to “OFF”).

902052

3-25

E

000910

q

EMU01412

TRIMMING OUTBOARD

MOTOR

The trim angle of the outboard motor
helps determine the position of the bow
of the boat in the water. The correct trim
angle will help improve performance and
fuel economy while reducing strain on the
engine. The correct trim angle depends
upon the combination of boat, engine,
and propeller. Correct trim is also affected
by variables such as the load in the boat,
sea conditions, and running speed.

w

Excessive trim for the operating condi­tions (either trim up or trim down) can
cause boat instability and can make
steering the boat more difficult. This
increases the possibility of an accident. If
the boat begins to feel unstable or is hard
to steer, slow down and/or readjust the
trim angle.

NOTE:

Refer to the section “ADJUSTING TRIM
ANGLE” for instructions on usage.

1 Trim operating angle

3-26

E

404022*

q

25

25-3/30

q

404015*

ADJUSTING TRIM ANGLE

EMU00951

Manual tilt model

There are 4 or 5 holes provided in the
clamp bracket to adjust the outboard
motor trim angle.

1) Stop the engine.

2) Remove the trim angle adjusting rod

1 from the clamp bracket while tilting
the motor up slightly.

3) Reposition the rod in the desired hole.

To raise the bow (“trim-out”), move the
rod away from the transom.
To lower the bow (“trim-in”), move the
rod toward the transom.
Make test runs with the trim set to differ­ent angles to find the position that works
best for your boat and operating condi­tions.

w

8 Stop the engine before adjusting the

trim angle.

8 Use care to avoid being pinched when

removing or installing the rod.

8 Use caution when trying a trim position

for the first time. Increase speed gradu­ally and watch for any signs of instabili­ty or control problems. Improper trim
angle can cause loss of control.

NOTE:

The outboard motor trim angle can be
changed approximately 4 degrees by
shifting the trim adjusting-rod one hole.

3-27

1

2

105011

E

EMU00282

Bow Up

When the boat is on plane, a bow-up atti­tude result in less drag, greater stability
and efficiency. This is generally when the
keel line of the boat is up about 3 to 5
degrees. When trimmed out, the boat
may have more tendency to steer to one
side or the other. Compensate for this as
you steer. The trim tab can also be adjust­ed to help offset this effect.

Too much trim-out puts the bow of the
boat too high in the water. Performance
and economy are decreased because the
hull of the boat is pushing the water and
there is more air drag.
Excessive trim-up can cause the propeller
to ventilate, which reduces performance
further. When trimmed-out too much, a
boat may “porpoise” (hop in the water),
which could throw the operator and pas­sengers overboard.

EMU00283

Bow Down

When the bow of the boat is down, it is
easier to accelerate from a standing start
onto plane.

3

105013

105015

Too much trim-in causes the boat to
“plow” through the water, decreasing
fuel economy and making in hard to
increase speed.
Operating with excessive trim-in at higher
speeds also makes the boat unstable.
Resistance at the bow is greatly
increased, heightening the danger of
“bow steering” and making operation dif­ficult and dangerous.

1 Bow up
2 Bow down
3 Optimum angle

3-28

E

000832

EMG70011

CRUISING IN SHALLOW

WATER

Manual tilt model

The outboard motor can be tilted up par­tially to allow operation in shallow water.

w

8 Place the gear shift in the Neutral posi-

tion before using the shallow water
cruising system.

8 Run the boat at the lowest possible

speed when using the shallow water
cruising system. The tilt-lock mecha­nism does not work while the shallow
water cruising system is being used.
Hitting an underwater obstacle could
cause the engine to lift out of the
water, resulting in loss of control.

8 Use extra care when operating in

reverse. Too much reverse thrust can
cause the engine to lift out of the
water, increasing the chance of acci­dent and personal injury.

8 Return the engine to its normal posi-

tion as soon as the boat is back in
deeper water.

25

402061**

cC

Place the gear-shift in the Neutral posi­tion before using the shallow water cruis­ing system.

EMG71310

PROCEDURE

25

1) Place the gear shift lever in the neu-

tral position.

2) Push the tilt lock lever down to

release.

3-29

E

402072*

403023*

402075

25

25

25-3/30

3) Pull up the shallow water lever.

4) Slightly tilt up the engine. The tilt­support bar will lock automatically,
supporting the engine in a partially
raised position.

NOTE:

If the engine is tilted up completely, the
tilt-lock lever automatically locks. The
shallow water lever is no longer effective.

5) When lowering the engine, set the tilt­lock lever and shallow water lever to
the lock position. Slightly tilt up the
engine until the tilt-support bar auto­matically returns to the free position.
Then, slowly lower the engine to the
normal position.

EMG80511*

PROCEDURE

25-3/30

1) Push the shallow water lever down to
the release position.

2) For setting the outboard motor at the
partially tilted position, slightly tilt up
the engine until the plate turns com­pletely

25-3/30

3) To return the engine to the normal
position, put the engine in Neutral,
then slightly tilt up the engine. Set the
tilt-lock lever and shallow water lever
to the lock position and slowly tilt the
engine down.

412022

3-30

E

105031

EMH10110

TILTING UP/DOWN

If the engine will be stopped for some
time, or if the boat is moored in shallows,
the engine should be tilted up to protect
the propeller and casing from damage by
collision with obstructions, and also to
reduce salt corrosion.

cC

8 Before tilting the motor, follow the pro-

cedures under “STOPPING ENGINE”.
Never tilt the motor while the engine is
running. Severe damage from over­heating can result.

8 Do not tilt up the engine by pushing

the steering handle as this could break
the handle.

8 Keep the power unit higher than the

propeller at all times. Otherwise, water
can run into the cylinder, causing dam­age.

w

Be sure all people are clear of the out­board motor when adjusting the tilt
angle, also be careful not to pinch any
body parts between the drive unit and
engine bracket.

w

Leaking fuel is a fire hazard. Disconnect
the fuel line if the engine will be tilted for
more than a few minutes. Otherwise, fuel
may leak. (If the fuel connector is provid­ed on the motor.)

3-31

N

406012

402061**

E

EMG63910

PROCEDURE FOR TILTING UP

25

1) Place the gear shift lever in Neutral.

2) Remove the fuel line connection from
the motor.

3) Push the tilt lock lever to release.

4) Pull up the shallow water lever.

402075*

5) Hold the rear of the top cowling with
one hand and fully tilt the engine up.

6) The tilt support bar turns to the
locked position automatically.

3-32

402035

403024

E

EMG63010*

PROCEDURE FOR TILTING UP

25-3/30

1) Remove the fuel-line connection from

the motor. (If the fuel connector is
provided on the motor.)

2) Place the tilt-lock lever in Release.

3) Hold the rear of the top cowling with

one hand, tilt the engine up, and turn
the tilt-support lever to the locked
position and support the engine.

EMG73410

PROCEDURE FOR TILTING DOWN

25

1) Return the shallow water lever.

2) Slightly tilt up the engine until the tilt

support bar is released automatically.

3) Tilt down the engine.

402075*

403036

EMG73210

PROCEDURE FOR TILTING DOWN

25-3/30

1) Return the tilt support lever tilting up

the engine slightly.

2) Tilt down the engine.

3-33

E

EMH60010

CRUISING IN OTHER

CONDITIONS

CRUISING IN SALT WATER

After operating in salt water, wash out the
cooling-water passages with fresh water
to prevent them from becoming clogged­up with salt deposits.

NOTE:

Refer to cooling system flushing instruc­tions in “TRANSPORTING AND STORING
OUTBOARD MOTOR”.

CRUISING IN TURBID WATER

It is strongly recommended that the
optional chromium-plated water-pump kit
be installed if the outboard is to be used
in turbid (muddy) water conditions.

3-34

-MEMO-

E

E

EMK00010

Chapter 4

MAINTENANCE

SPECIFICATION DATA.............................4-1

TRANSPORTING AND STORING

OUTBOARD MOTOR ...............................4-4

Trailering outboard motor...................4-4

Storing outboard motor ......................4-5

PERIODIC MAINTENANCE....................4-10

Replacement parts .............................4-10

Maintenance chart..............................4-11

Cleaning and adjusting spark plug..4-12

Checking fuel system.........................4-14

Inspecting fuel filter ...........................4-15

Adjusting idling speed.......................4-16

Checking water drain under

engine oil tank ....................................4-17

Replacing fuse ...................................4-18

Checking wiring and connectors ......4-18

Exhaust leakage..................................4-18

Water leakage .....................................4-18

Greasing ..............................................4-19

Checking propeller .............................4-22

Changing gear oil ...............................4-24

Cleaning fuel tank...............................4-25

Inspecting and replacing anode(s) ...4-26

Checking battery.................................4-27

Checking bolts and nuts ....................4-30

Motor exterior.....................................4-30

Coating the boat bottom ...................4-30

1

2

3

4

5

6

EMK10011*

E

SPECIFICATION DATA

Item

DIMENSIONS

8Overall Length mm (in.)
8Overall Width mm (in.)
8Overall Height S/L mm (in.)
8Transom height S/L mm (in.)
8Weight S/L kg (lb.)

PERFORMANCE

8Full throttle operating range r/min
8Maximum output kW (HP)
8Idling speed r/min

ENGINE

8Type

Number of cylinder
Displacement cm

× stroke mm (in.)

Bore

8Ignition system
8Spark plug NGK

Spark plug gap mm (in.)

8Control system
8Starting system
8Battery capacity V-AH

Minimum cold crank performance Amps at –17.8°C (0°F)
Minimum reserve capacity minutes at 26.7°C (80°F)

8Alternator output V-A (W)
8Starting carburetion system

DRIVE UNIT

8Gear positions

Gear ratio

8Trim/tilt system
8Propeller mark

FUEL AND OIL

8Fuel

Fuel tank capacity L (US gal, Imp gal)

8Recommended engine oil

Oil tank capacity L (US qt, Imp qt)

8Fuel/oil ratio
8Recommended gearcase oil

Gear oil capacity cm

TIGHTENING TORQUE

8Spark plug N•m (kgf•m, lb•ft)
8Propeller nut N•m (kgf•m, lb•ft)

Model

Unit 25MHA

3

(cu.in.)

3

(US oz, Imp oz)

4-1

936 (369)
358 (14.1)
1,068 (42.0)/1,195 (47.0)
419 (16.5)/546 (21.5)

49.0 (108.0)/50.5 (111.3)

5,000~6,000

18.4 (25) at 5,500 r/min
700~800

2-stroke, L
2
395 (24.1)
67 × 56 (2.6 × 2.2)
C.D.I system
B7HS-10

0.9~1.0 (0.035~0.039)
Tiller control
Manual start
—
—
—
12V-(80W)
Choke start system

Forward-Neutral-Reverse

2.08 (27/13)
Manual
F

Regular-unleaded gasoline
(P.O.N.: minimum 86)
25 (6.6, 5.5)
YAMALUBE 2 STROKE OUTBOARD OIL or
an equivalent TC-W3 certified outboard oil.
—
100 : 1
Hypoid gear oil (SAE 90)
370 (12.5, 13.0)

25 (2.5, 18)
35 (3.5, 25)

25MHA3 30MHA 30EHA

E

993 (39.1)
360 (14.2)
1,158 (45.6)/—
424 (16.7)/—

59.0 (130.1)/—

4,500~5,500

18.4 (25) at 5,000 r/min
700~800

2-stroke, L
3
496 (30.3)

59.5 × 59.5 (2.3 × 2.3)
C.D.I system
B7HS-10

0.9~1.0 (0.035~0.039)
Tiller control
Manual start
—
—
—
12V-(80W)
Choke start system

Forward-Neutral-Reverse

1.85 (24/13)
Manual
F

993 (39.1)
360 (14.2)
1,158 (45.6)/1,279 (50.4)
424 (16.7)/545 (21.5)

60.0 (132.3)/62.0 (136.7)

4,500~5,500

22.1 (30) at 5,000 r/min
700~800

2-stroke, L
3
496 (30.3)

59.5 × 59.5 (2.3 × 2.3)
C.D.I system
B7HS-10

0.9~1.0 (0.035~0.039)
Tiller control
Manual start
—
—
—
12V-(80W)
Choke start system

Forward-Neutral-Reverse

1.85 (24/13)
Manual
F

993 (39.1)
360 (14.2)
— /1,279 (50.4)
— /545 (21.5)
— /64.5 (142.2)

4,500~5,500

22.1 (30) at 5,000 r/min
700~800

2-stroke, L
3
496 (30.3)

59.5 × 59.5 (2.3 × 2.3)
C.D.I system
B7HS-10

0.9~1.0 (0.035~0.039)
Tiller control
Electric start
12-40~70
210
40
12V-6A
Choke start system

Forward-Neutral-Reverse

1.85 (24/13)
Manual
F

Regular-unleaded gasoline
(P.O.N.: minimum 86)
25 (6.6, 5.5)
YAMALUBE 2 STROKE OUTBOARD OIL or
an equivalent TC-W3 certified outboard oil.
—
100 : 1
H

ypoid gear oil (SAE 90)

200 (6.8, 7.0)

25 (2.5, 18)
35 (3.5, 25)

Regular-unleaded gasoline
(P.O.N.: minimum 86)
25 (6.6, 5.5)
YAMALUBE 2 STROKE OUTBOARD OIL or an
equivalent TC-W3 certified outboard oil.
Engine: 0.9 (1.0, 0.8)
—
Hypoid gear oil (SAE 90)
370 (12.5, 13.0)

25 (2.5, 18)
35 (3.5, 25)

Regular-unleaded gasoline
(P.O.N.: minimum 86)
25 (6.6, 5.5)
YAMALUBE 2 STROKE OUTBOARD OIL or
an equivalent TC-W3 certified outboard oil.
Engine: 0.9 (1.0, 0.8)
—
Hypoid gear oil (SAE 90)
370 (12.5, 13.0)

25 (2.5, 18)
35 (3.5, 25)

4-2

EMK10011*

E

SPECIFICATION DATA

Item

Model

DIMENSIONS

8Overall Length mm (in.)
8Overall Width mm (in.)
8Overall Height S/L mm (in.)
8Transom height S/L mm (in.)
8Weight S/L kg (lb.)

PERFORMANCE

8Full throttle operating range r/min
8Maximum output kW (HP)
8Idling speed r/min

ENGINE

8Type

Number of cylinder
Displacement cm
Bore × stroke mm (in.)

8Ignition system
8Spark plug NGK

Spark plug gap mm (in.)

8Control system
8Starting system
8Battery capacity V-AH

Minimum cold crank performance Amps at –17.8°C (0°F)
Minimum reserve capacity minutes at 26.7°C (80°F)

8Alternator output V-A (W)
8Starting carburetion system

DRIVE UNIT

8Gear positions

Gear ratio

8Trim/tilt system
8Propeller mark

FUEL AND OIL

8Fuel

Fuel tank capacity L (US gal, Imp gal)

8Recommended engine oil

Oil tank capacity L (US qt, Imp qt)

8Fuel/oil ratio
8Recommended gearcase oil

Gear oil capacity cm

TIGHTENING TORQUE

8Spark plug N•m (kgf•m, lb•ft)
8Propeller nut N•m (kgf•m, lb•ft)

Unit 30ERA

3

(cu.in.)

3

(US oz, Imp oz)

4-3

662 (26.1)
307 (12.1)
— /1,261 (49.6)
— /545 (21.5)
— /62.0 (136.7)

4,500~5,500

22.1 (30) at 5,000 r/min
700~800

2-stroke, L
3
496 (30.3)

59.5 × 59.5 (2.3 × 2.3)
C.D.I system
B7HS-10

0.9~1.0 (0.035~0.039)
Remote control
Electric start
12-40~70
210
40
12V-6A
Choke start system

Forward-Neutral-Reverse

1.85 (24/13)
Manual
F

Regular-unleaded gasoline
(P.O.N.: minimum 86)
25 (6.6, 5.5)
YAMALUBE 2 STROKE OUTBOARD OIL or
an equivalent TC-W3 certified outboard oil.
Engine: 0.9 (1.0, 0.8)
—
Hypoid gear oil (SAE 90)
370 (12.5, 13.0)

25 (2.5, 18)
35 (3.5, 25)

E

000929

EMU01369*

TRANSPORTING AND

STORING

OUTBOARD MOTOR

w

Leaking fuel is a fire hazard. When trans­porting and storing the outboard motor,
close the air vent screw and fuel cock to
prevent fuel from leaking.

TRAILERING OUTBOARD MOTOR

The motor should be trailered and stored
in the normal running position. If there is
insufficient road clearance in this position,
then trailer the motor in the tilt position
using a motor support device such as a
transom saver bar.

cC

Do not use the tilt support lever/knob
when trailering the boat. The outboard
motor could shake loose from the tilt
support and fall. If the motor can not be
trailered in the down position, use an
additional support device to secure it in
the up position.

w

8 Never get under the lower unit while it

is tilted, even if a motor support bar is
used. Severe injury could occur if the
outboard accidentally falls.

8 USE CARE when transporting fuel tank,

whether in a boat or car.
DO NOT fill fuel container to maximum
capacity.
Gasoline will expand considerably as it
warms up and can build up pressure in
the fuel container. This can cause fuel
leakage and a potential fire hazard.

4-4

E

102013

When transporting or storing the out­board motor while removed from a boat,
fold the tiller handle and lean the motor
on the tiller handle to keep in a horizontal
position.

NOTE:

Place a towel or the like under the out­board motor to protect it from damage.

cC

Keep the power unit higher than the pro­peller at all times. Otherwise, cooling
water can run into the cylinder, which
could result in damage.

EMK16010

STORING OUTBOARD MOTOR

When storing your Yamaha outboard for
prolonged periods of time, (2 months or
longer), several important procedures
must be performed to prevent expensive
damage. This is especially important for
your Precision Blend equipped outboard
due to the lean oil ratios used at idle prior
to shutting the engine off for the season.
It is advisable to have your outboard ser­viced by an authorized Yamaha dealer
prior to storage. However, the following
procedures can be performed by you, the
owner, with a minimum of tools.

4-5

E

605024

q

w

EMK21010

Filling Fuel Tank

Fill the fuel tank with fresh fuel and add
one ounce of “Yamaha Fuel Conditioner
and Stabilizer” (Part No. LUB-FUELC-12-

00) to each gallon of fuel.

NOTE:

The use of “Yamaha Fuel Conditioner and
Stabilizer” eliminates the need to drain
the fuel system. Consult your Yamaha
dealer or other qualified mechanic if the
fuel system is to be drained instead.

EMK22211

Flushing Cooling System and Fogging
Engine

Cooling system flushing is essential to
prevent the cooling system from clogging
up with salt, sand, or dirt. In addition, fog­ging of the engine is mandatory to pre­vent expensive engine damage due to
rust. Perform the flushing and fogging at
the same time.

1) Remove the cowling.

2) Install the outboard motor on the
water tank, and fill the tank with fresh
water to above the level of the anti­cavitation plate.

1 Water surface
2 Lowest water level

cC

If the fresh water level is below the level
of the anti-cavitation plate, or if the water
supply is insufficient, engine seizure may
occur.

4-6

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8 Do not touch or remove electrical parts

when starting or during operation.

8 Keep hands, hair and clothes away

from flywheel and other rotating parts
while engine is running.

3) Run the engine at a fast idle for 10~15

minutes.

4) Just prior to turning off the engine,

quickly spray “Yamaha Stor-Rite
Engine Fogging Oil” (Part No. LUB­STRRT-12-00) alternately into carbu­retor. When properly done, the
engine will smoke excessively and
almost stall.

5) Turn off the engine and water supply.

EMK26111

Lubrication

1) Remove the spark plugs, and spray a

10 second spray of “Yamaha Stor­Rite Engine Fogging Oil” into each
cylinder. Grease the spark plug
threads and reinstall the spark plugs
and torque to proper specification.
(Refer to “CLEANING AND ADJUST­ING SPARK PLUG”.)

2) Turn the engine over with the stop

lanyard disconnected to work the fog­ging oil into the piston rings.

3) Fill the oil tanks. This prevents the for-

mation of condensation. For models
with a remote tank, it may be neces­sary to manually override the control
unit to completely fill the engine main
tank. (Refer to “TEMPORARY ACTION
IN EMERGENCY”).

4-7

E

4) Change the lower unit oil. (Refer to
“CHANGING GEAR OIL”). Inspect the
oil for the presence of water which
indicates a leaky seal. Seal replace­ment should be performed by an
authorized Yamaha dealership prior
to use.

5) Grease all grease fittings. (Refer to
“GREASING”)

EMK27011

Cleaning and Anti-corrosion Measure

1) Wash down the exterior of the out­board with fresh water and dry off
completely.

2) Spray the engine’s exterior with
“Yamaha Silicone Protectant” (Part
No. LUB-SILCNE-13-00).

3) Wax the cowling with a non-abrasive
wax such as “Yamaha Silicone Wax”
(Part No. ACC-11000-15-02).

4-8

E

EMU00353

Battery Care

w

Battery electrolyte is poisonous and dan­gerous, causing severe burns, etc. It con­tains sulfuric acid. Avoid contact with
skin, eyes, or clothing.
Antidote:
EXTERNAL; Flush with water.
INTERNAL; Drink large quantities of
water or milk. Follow with milk of mag­nesia, beaten egg, or vegetable oil. Call
physician immediately.
EYES; Flush with water for 15 minutes
and get prompt medical attention.
Batteries produce explosive gases: Keep
sparks, flame, cigarettes, etc. away. Ven­tilate when charging or using in a closed
space. Always wear eye protection when
working near batteries.
KEEP OUT OF REACH OF CHILDREN.

Batteries vary among manufacturers.
Therefore the following procedures may
not always apply. Consult your battery
manufacturer’s instructions.

1) Disconnect and remove the battery

from the boat. Always disconnect the
black negative lead first to prevent the
risk of shorting.

2) Clean the battery casing and termi-

nals. Fill each cell to the upper level
with distilled water.

3) Store the battery on a level surface in

a cool, dry, well-ventilated place out
of direct sunlight.

4) Once a month, check the specific

gravity of the electrolyte and recharge
as required to prolong battery life.

4-9

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EMK32110

PERIODIC MAINTENANCE

w

Be sure to turn off the engine when you
perform maintenance unless otherwise
specified. If the owner is not familiar with
machine servicing, this work should be
done by a Yamaha dealer or other quali­fied mechanic.

A service manual is available for purchase
through a Yamaha dealer for owners who
have the mechanical skills, tools, and
other equipment necessary to perform
maintenance not covered by this owner’s
manual.

EMK33011

REPLACEMENT PARTS

If replacement parts are necessary, use
only genuine Yamaha parts or equiva­lents of the same type and of equivalent
strength and materials. Any part of inferi­or quality may malfunction, and the
resulting loss of control could endanger
the operator and passengers.
Yamaha genuine parts and accessories
are available from a Yamaha dealer.

4-10

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EMK30012*

MAINTENANCE CHART

Frequency of maintenance operations may be adjusted according to the operating con­ditions, but the following table gives general guidelines.

The mark (7) indicates the check-ups which you may carry out yourself.
The mark (2) indicates work to be carried out by your Yamaha dealer.

Interval

Item

Spark plug(s)

Grease points Greasing ●
Fuel system Inspection ● ● 4-14
Fuel filter Cleaning/Replacement ● ● ● 4-15
Fuel tank *1 Cleaning ● 4-25
Idling speed Inspection/Adjustment ● ● 4-16
Oil tank water drain Cleaning ● ● ● 4-17
Oil pump Inspection/Adjustment
Propeller Inspection ● ● ● 4-22
Gear oil Change ● ● 4-24
Anode(s) Inspection/Replacement
Wiring/Connector(s) Inspection/Reconnect ● ● ● 4-18
Exhaust leakage Inspection ● ● ● 4-18
Water leakage Inspection ● ● ● 4-18
Bolts/Nuts Retightening ● ● ● 4-30
Cowling clamp(s) Inspection/Adjustment ● —
Motor exterior Inspection ● ● ● 4-30
Cooling water passages *2

Battery Inspection/Charge

Cleaning/Adjustment/

Replacement

Flushing ● ● —

Initial Every

10 hours

● ● ● 4-12

1

● (every

month)

50 hours 100 hours 200 hours

(3 months) (6 months) (1 year)

1 1

Refer
Page

4-19, 4-20, 4-21

—

4-26

4-27

*1.If a portable fuel tank is equipped.
*2.When operating in salt water, turbid or muddy water, the engine should be flushed with clean

water after each use.

4-11

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EMU01202

CLEANING AND ADJUSTING SPARK
PLUG

w

When removing or installing a spark plug,
be careful not to damage the insulator. A
damaged insulator could allow external
sparks, which could lead to explosion or
fire.

The spark plug is an important engine
component and is easy to inspect. The
condition of the spark plug can indicate
something about the condition of the
engine. For example, if the center elec­trode porcelain is very white, this could
indicate an intake air leak or carburetion
problem in that cylinder. Do not attempt
to diagnose any problems yourself.
Instead, take the outboard motor to a
Yamaha dealer. You should periodically
remove and inspect the spark plug
because heat and deposits will cause the
spark plug to slowly break down and
erode. If electrode erosion becomes
excessive, or if carbon and other deposits
are excessive, you should replace the
spark plug with another of the correct
type.

Standard spark plug:
Refer to “SPECIFICATIONS”, page 4-1.

Before fitting the spark plug, measure the
electrode gap with a wire thickness
gauge; adjust the gap to specification if
necessary.

Spark plug gap:
Refer to “SPECIFICATIONS”, page 4-1.

4-12

E

When fitting the plug, always clean the
gasket surface and use a new gasket.
Wipe off any dirt from the threads and
screw in the spark plug to the correct
torque.

Spark plug torque:
Refer to “SPECIFICATIONS”, page 4-1.

NOTE:

If a torque-wrench is not available when
you are fitting a spark plug, a good esti­mate of the correct torque is 1/4 to 1/2 a
turn past finger-tight. Have the spark plug
adjusted to the correct torque as soon as
possible with a torque-wrench.

w

q

903022

Initial of spark
plug I.D. mark

B 21 mm (13/16 in.)

C/BK 16 mm (5/8 in.)

D 18.3 mm (23/32 in.)

1 Spark plug gap
2 Spark plug I.D. mark (NGK)

Plug-wrench size

4-13

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25

25-3/30

EMK38010

CHECKING FUEL SYSTEM

w

Gasoline (petrol) and its vapors are highly
flammable and explosive. Keep away
from sparks, cigarettes, flames or other
sources of ignition.

Check the fuel line for leaks, cracks, or
malfunctions. If any problem is found, it
should be repaired immediately by Yama­ha dealer or other qualified mechanic.

Checking points

8 Fuel system parts leakage.
8 Fuel hose joint leakage.
8 Fuel hose cracks or other damage.
8 Fuel connector leakage.

w

Leaking fuel can result in fire or explo­sion.

8 Check for fuel leakage regularly.
8 If any fuel leakage is found, the fuel

system must be repaired by a qualified
mechanic. Improper repairs can make
the outboard unsafe to operate.

4-14

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EMU00370

INSPECTING FUEL FILTER

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Gasoline (petrol) is highly flammable, and
its vapors are flammable and explosive.
8 If you have any question about properly

doing this procedure, consult your
Yamaha dealer.

8 Do not perform this procedure on a hot

or running engine. Allow the engine to
cool.

8 There will be fuel in the fuel filter. Keep

away from sparks, cigarettes, flames or
other sources of ignition.

8 This procedure will allow some fuel to

spill. Catch fuel in a rag. Wipe up any
spilled fuel immediately.

8 The fuel filter must be reassembled

carefully with O-ring, filter cup, and
hoses in place. Improper assembly or
replacement can result in a fuel leak,
which could result in a fire or explosion
hazard.

EMU00371

1) Remove the nut holding the fuel filter

assembly if equipped.

2) Unscrew the filter cup, catching any

spilled fuel in a rag.

3) Remove the filter element, and wash

it in solvent.
Allow it to dry. Inspect the filter ele­ment and O-ring to make sure they
are in good condition. Replace them if
necessary.

4) Reinstall the filter element in the cup.

Make sure the O-ring in position in
the cup. Firmly screw the cup onto
the filter housing.

4-15

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207013*

q

w

e

r

5) Attach the filter assembly to the
bracket with that the fuel hoses are
attached to the filter assembly.

6) Run the engine and check the filter
and lines for leaks.

1 Filter element
2 O-ring
3 Filter cap
4 Filter housing

EMU00376

ADJUSTING IDLING SPEED

w

8 Do not touch or remove electrical parts

when starting or during operation.

8 Keep hands, hair and clothes away

from flywheel and other rotating parts
while engine is running.

cC

This procedure must be performed while
the outboard motor is in the water. A
flushing attachment or test tank can be
used.

A diagnostic tachometer should be used
for this procedure.

1) Start the engine and allow it to warm
up fully in Neutral until it is running
smoothly. If the outboard is mounted
on a boat, be sure the boat is tightly
moored.

4-16

E

q

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q

25

25-3/30

q

204023

2) Adjust the throttle stop-screw to set

the idling speed to specification (see
“SPECIFICATIONS”) by turning the
stop-screw clockwise to increase the
idling speed, and turning it counter­clockwise to decrease the idling
speed.

NOTE:

Correct idling-speed adjustment is only
possible if the engine is fully warmed-up.
If not warmed up fully, the speed setting
will tend to be too high. If you have diffi­culty obtaining the specified idle, consult
a Yamaha dealer or other qualified
mechanic.

1 Throttle stop-screw

EMK58010

CHECKING WATER DRAIN UNDER
ENGINE OIL TANK

A translucent water drain hose is connect­ed from the bottom of the oil tank to the
filler neck. If water or foreign matter col­lects in this hose, immediately remove
the hose at the filler neck and drain the
contaminants.

1 Hose
2 Filler neck side

4-17

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205021

30

25

q

q

w

w

EMU01329

REPLACING FUSE

If the fuse has blown on an Electric start
model, open the fuse holder and replace
the fuse with a new one of proper amper­age.

w

Be sure to use the specified fuse. An
incorrect fuse or a piece of wire may
allow excessive current flow. This could
cause electrical system damage and a fire
hazard.

NOTE:

If the new fuse blows again immediately,
consult a Yamaha dealer.

1 Fuse holder
2 Fuse (10A)

EMK78010

CHECKING WIRING AND
CONNECTORS

1) Check that each grounding wire is
properly secured.

2) Check that each connector is engaged
securely.

EXHAUST LEAKAGE

Start the engine and check that no
exhaust leaks from the joints between the
exhaust cover, cylinder head and crank
case.

WATER LEAKAGE

Start the engine and check that no water
leaks from the joints between the exhaust
cover, cylinder head and crank case.

4-18

MU00366

103141b

GREASING

Yamaha marine grease
(Water resistant grease)

25

E

4-19

103141a

EMU00366

GREASING

Yamaha marine grease
(Water resistant grease)

25-3/30

E

4-20

EMU00366

GREASING

Yamaha marine grease
(Water resistant grease)

30

E

4-21

210012

602051

602054

602052*

E

EMU00388

CHECKING PROPELLER

w

You could be seriously injured if the
engine accidentally starts while you are
near the propeller.
8 Before inspecting, removing or

installing the propeller, remove the
spark plug caps from the spark plugs.
Also, put the shift control in Neutral,
put the main switch in the “OFF” posi­tion and remove the key, and remove
the lanyard from the engine stop
switch. Turn off the battery cut-off
switch if your boat has one.

8 Do not use your hand to hold the pro-

peller when loosening or tightening the
propeller nut. Put a wood block
between the cavitation plate and the
propeller to prevent the propeller from
turning.

EMU00390

Propeller Checking Point

8 Check each of the propeller blades for

wear, erosion from cavitation or ventila­tion, or other damage.

8 Check the splines for wear and damage.
8 Check for fish line winding around the

propeller shaft.

8 Check the propeller shaft oil seal for

damage.

EMU00393

Removing the Propeller

1) Using the pliers provided, straighten
the cotter-pin and pull it out.

2) Remove the propeller nut, washer
and spacer.

3) Remove the propeller and thrust
washer.

4-22

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602045

1

2

3

4

5

6

1 Thrust washer
2 Propeller
3 Spacer
4 Washer
5 Propeller nut
6 Cotter pin

EMU00397

Installing the Propeller

cC

8 Be sure to install the thrust washer

before installing propeller, otherwise,
lower case and propeller boss may be
damaged.

8 Be sure to use a new cotter pin and

bend the ends over securely. Other­wise, the propeller could come off dur­ing operation and be lost.

1) Apply Yamaha Marine grease or Cor-

rosion resistant grease to the pro­peller-shaft.

2) Install the thrust washer and propeller

on the propeller-shaft.

3) Install the spacer and washer. Tighten

the propeller nut to the specified
torque.

602053

Tightening torque:
Refer to “SPECIFICATIONS” page 4-1.

4) Align the propeller nut with the pro-

peller shaft hole. Insert a new cotter
pin in the hole and bend the cotter pin
ends.

NOTE:

If the propeller nut does not align with the
propeller shaft hole after tightening to the
specified torque, then tighten the nut fur­ther to align it with the hole.

cC

Be sure to use a new cotter pin and bend
the ends over securely. Otherwise, the
propeller could come off during operation
and be lost.

4-23