Yamaha 40V User manual

OWNER’S MANUAL
40V
40Y
50H
63B-28199-79-E0

EMU25050
Read this owner’s manual carefully before operating your outboard motor.

Important manual information
EMU25100
To the owner
Thank you for choosing a Yamaha outboard
motor. This Owner’s Manual contains infor-
mation needed for proper operation, mainte-
nance and care. A thorough understanding
of these simple instructions will help you ob-
tain maximum enjoyment from your new
Yamaha. If you have any question about the
operation or maintenance of your outboard
motor, please consult a Yamaha dealer.
In this Owner’s Manual particularly important
information is distinguished in the following
ways.
The Safety Alert Symbol means
ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!
WARNING
EWM00780
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 out-
board motor.
CAUTION:
ECM00700
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 advancements in
product design and quality. Therefore, while
this manual contains the most current prod-
uct information available at the time of print-
ing, there may be minor discrepancies
between your machine and this manual. If
there is any question concerning this manu-
al, please consult your Yamaha dealer.
NOTE:
The 40VEO, 40VETO, 40VMHO, 40YETO,
40YMHO, 50HEDO, 50HETO, 50HMHO and
the standard accessories are used as a base
for the explanations and illustrations in this
manual. Therefore some items may not ap-
ply to every model.
EMU25120
40V, 40Y, 50H
OWNER’S MANUAL
©2004 by Yamaha Motor Co., Ltd.
1st Edition, April 2004
All rights reserved.
Any reprinting or unauthorized use
without the written permission of
Yamaha Motor Co., Ltd.
is expressly prohibited.
Printed in Japan

Table of contents
General information .......................... 1
Identification numbers record........... 1
Outboard motor serial number .......... 1
Key number....................................... 1
EC label............................................ 1
Safety information ............................ 2
Important labels................................ 3
Warning labels .................................. 3
Fueling instructions .......................... 3
Gasoline............................................ 4
Engine oil .......................................... 4
Battery requirement.......................... 4
Battery specifications ........................ 4
Propeller selection............................ 4
Start-in-gear protection .................... 5
Basic components ............................ 6
Main components............................. 6
Fuel tank ........................................... 8
Fuel joint ........................................... 9
Fuel gauge ........................................ 9
Fuel tank cap .................................... 9
Air vent screw ................................... 9
Remote control.................................. 9
Remote control lever......................... 9
Neutral interlock trigger................... 10
Neutral throttle lever........................ 10
Tiller handle .................................... 10
Gear shift lever................................ 10
Throttle grip..................................... 11
Throttle indicator ............................. 11
Throttle friction adjuster................... 11
Engine stop lanyard switch ............. 12
Engine stop button .......................... 12
Choke knob for pull type ................. 13
Manual starter handle ..................... 13
Main switch ..................................... 13
Steering friction adjuster ................. 13
Steering friction adjuster ................. 14
Power trim and tilt switch on remote
control or tiller handle ................... 14
Power trim and tilt switch on bottom
engine cowling .............................. 14
Trim tab with anode ........................ 15
Trim rod (tilt pin).............................. 15
Tilt lock mechanism......................... 15
Tilt support lever for power trim and
tilt or hydro tilt model.....................16
Tilt support lever for manual tilt
model ............................................ 16
Top cowling lock lever(s) (turn
type) .............................................. 16
Warning indicator for three
indicators....................................... 17
Warning indicator ............................ 17
Tachometer ..................................... 17
Digital tachometer ........................... 17
Oil level indicators (three
indicators 2) .................................. 18
Oil level indicator (digital type) ........ 18
Overheat warning indicator ............. 18
Overheat warning indicator
(digital type) .................................. 18
Trim meter ....................................... 19
Trim meter (digital type) .................. 19
Hour meter (digital type)..................19
Warning system ............................. 20
Overheat warning ............................ 20
Oil level warning and oil filter
clogging warning ........................... 21
Operation ......................................... 23
Installation...................................... 23
Mounting the outboard motor .......... 23
Clamping the outboard motor..........24
Breaking in engine ......................... 25
Gasoline and engine oil mixing
chart (50:1).................................... 25
Procedure for oil injection models ... 25
Preoperation checks ...................... 26
Fuel ................................................. 26
Oil .................................................... 26
Controls ........................................... 26
Engine ............................................. 26
Operation after long period of
storage .......................................... 26
Filling fuel and engine oil ............... 27
Filling fuel for portable tank ............. 27
Filling oil for manual starter
model ............................................ 27
Filling oil for electric start models .... 28
Oil level indicator operation............. 29

Table of contents
Operating engine............................ 30
Feeding fuel (portable tank) ............ 30
Starting engine................................ 31
Warming up engine ........................ 34
Choke start models ......................... 34
Electric start and prime start
models .......................................... 34
Shifting ........................................... 35
Forward (tiller handle and remote
control models) ............................. 35
Reverse (automatic reverse lock
and power trim and tilt models)..... 35
Reverse (manual tilt and hydro tilt
models) ......................................... 36
Stopping engine ............................. 37
Procedure ....................................... 37
Trimming outboard motor............... 37
Adjusting trim angle for manual tilt
models .......................................... 38
Adjusting trim angle ........................ 39
Adjusting trim angle for hydro tilt
models .......................................... 39
Adjusting boat trim .......................... 40
Tilting up and down ........................ 41
Procedure for tilting up.................... 41
Procedure for tilting up (hydro tilt
models) ......................................... 42
Procedure for tilting up.................... 42
Procedure for tilting down ............... 44
Procedure for tilting down (manual
and hydro tilt models) ................... 44
Procedure for tilting down ............... 44
Cruising in shallow water ...............45
Hydro tilt models ............................. 45
Power trim and tilt models / power
tilt models...................................... 46
Cruising in other conditions............ 47
Maintenance..................................... 48
Specifications ................................. 48
Transporting and storing outboard
motor ............................................ 50
Clamp screw mounting models....... 51
Storing outboard motor ................... 51
Procedure ....................................... 51
Lubrication (oil injection models)..... 52
Battery care ..................................... 52
Cleaning the outboard motor...........53
Checking painted surface of
motor............................................. 53
Periodic maintenance .................... 53
Replacement parts .......................... 53
Maintenance chart........................... 55
Greasing.......................................... 56
Cleaning and adjusting spark
plug ............................................... 57
Checking fuel system ...................... 58
Inspecting fuel filter ......................... 59
Cleaning fuel filter ...........................59
Inspecting idling speed....................60
Checking water in engine oil tank ...60
Checking wiring and connectors ..... 61
Exhaust leakage.............................. 61
Water leakage ................................. 61
Checking power trim and tilt
system........................................... 61
Checking propeller .......................... 62
Removing the propeller ................... 63
Installing the propeller ..................... 63
Changing gear oil ............................ 64
Cleaning fuel tank ...........................65
Inspecting and replacing
anode(s)........................................ 65
Checking battery (for electric start
models) ......................................... 66
Connecting the battery .................... 67
Disconnecting the battery................67
Checking top cowling ...................... 67
Coating the boat bottom.................. 68
Trouble Recovery............................ 69
Troubleshooting ............................. 69
Temporary action in emergency .... 72
Impact damage ............................... 72
Replacing fuse ................................ 72
Power trim and tilt will not
operate.......................................... 73
Starter will not operate .................... 73
Emergency starting engine .............74
Emergency starting engine .............75
Engine fails to operate ................... 76
Cold engine fails to start..................76

Table of contents
Treatment of submerged motor......77
Procedure ....................................... 77

1
General information
EMU25170
Identification numbers record
EMU25182
Outboard motor serial number
The outboard motor serial number is
stamped on the label attached to the port
side of the clamp bracket or the upper part of
the swivel bracket.
Record your outboard motor serial number in
the spaces provided to assist you in ordering
spare parts from your Yamaha dealer or for
reference in case your outboard motor is sto-
len.
EMU25190
Key number
If a main key switch is equipped with the mo-
tor, 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.
EMU25202
EC label
Engines affixed with this label conform to
certain portions of the European Parliament
directive relating to machinery. Refer to the
label and the EC Declaration of Conformity
for more details.
1. Outboard motor serial number location
1
ZMU02931
1. Key number
1. EC label location
1
ZMU04889

General information
2
EMU25370
Safety information
●
Before mounting or operating the outboard
motor, read this entire manual. Reading it
should give you an understanding of the
motor and its operation.
●
Before operating the boat, read any own-
er’s or operator’s manuals supplied with it
and all labels. Be sure you understand
each item before operating.
● Do not overpower the boat with this out-
board 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.
●
Do not modify the outboard. Modifications
could make the motor unfit or unsafe to
use.
●
Never operate after drinking alcohol or tak-
ing drugs. About 50% of all boating fatali-
ties involve intoxication.
●
Have an approved personal flotation de-
vice (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 condi-
tions.
●
Gasoline is highly flammable, and its va-
pors are flammable and explosive. Handle
and store gasoline carefully. Make sure
there are no gas fumes or leaking fuel be-
fore starting the engine.
● This product emits exhaust gases which
contain carbon monoxide, a colorless,
odorless gas which may cause brain dam-
age or death when inhaled. Symptoms in-
clude nausea, dizziness, and drowsiness.
Keep cockpit and cabin areas well ventilat-
ed. Avoid blocking exhaust outlets.
●
Check throttle, shift, and steering for prop-
er operation before starting the engine.
● 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.
●
Know the marine laws and regulations
where you will be boating - and obey them.
●
Stay informed about the weather. Check
weather forecasts before boating. Avoid
boating in hazardous weather.
●
Tell someone where you are going: leave
a Float Plan with a responsible person. Be
sure to cancel the Float Plan when you re-
turn.
●
Use common sense and good judgment
when boating. Know your abilities, and be
sure you understand how your boat han-
dles 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.
●
Always watch carefully for swimmers dur-
ing the engine operation.
● Stay away from swimming areas.
ZMU01696

General information
3
●
When a swimmer is in the water near you
shift into neutral and shut off the engine.
EMU25380
Important labels
EMU25395
Warning labels
EMU25401
Label
WARNING
EWM01260
● 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.
EMU25431
Label
WARNING
EWM01300
●
This engine is equipped with a neutral
starting device.
● The engine will not start unless the shift
control is in neutral position.
EMU25540
Fueling instructions
WARNING
EWM00010
GASOLINE AND ITS VAPORS ARE HIGH-
LY FLAMMABLE AND EXPLOSIVE!
●
Do not smoke when refueling, and keep
away from sparks, flames, or other
sources of ignition.
●
Stop engine before refueling.
●
Refuel in a well-ventilated area. Refuel
portable fuel tanks off the boat.
●
Take care not to spill gasoline. If gaso-
line spills, wipe it up immediately with
dry rags.
●
Do not overfill the fuel tank.
●
Tighten the filler cap securely after re-
fueling.
●
If you should swallow some gasoline,
inhale a lot of gasoline vapor, or get
gasoline in your eyes, get immediate
medical attention.
●
If any gasoline spills onto your skin, im-
mediately wash with soap and water.
Change clothing if gasoline spills on it.
●
Touch the fuel nozzle to the filler open-
ing or funnel to help prevent electro-
static sparks.
CAUTION:
ECM00010
Use only new clean gasoline which has
been stored in clean containers and is not
contaminated with water or foreign mat-
ter.
ZMU03342
ZMU03340

General information
4
EMU25580
Gasoline
If knocking or pinging occurs, use a different
brand of gasoline or premium unleaded fuel.
EMU25650
Engine oil
If the recommended engine oil is not avail-
able, another 2-stroke engine oil with an
NMMA-certified TC-W3 rating may be used.
EMU25690
Battery requirement
CAUTION:
ECM01060
Do not use a battery that does not meet
the specified capacity. If a battery which
does not meet specifications is used, the
electric system could perform poorly or
be overloaded, causing electric system
damage.
For electric start models, choose a battery
which meets the following specifications.
EMU25720
Battery specifications
EMU25741
Propeller selection
The performance of your outboard motor will
be critically affected by your choice of propel-
ler, 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 pro-
pellers 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 suit-
able as it enables the correct engine speed
to be maintained. Conversely, a larger-pitch
propeller is more suitable for a smaller oper-
ating 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 ap-
plication.
Recommended gasoline:
Regular unleaded gasoline with a min-
imum octane rating of 90 (Research
Octane Number).
Recommended engine oil:
YAMALUBE 2-stroke outboard motor
oil
Minimum cold cranking amps (CCA/EN):
40VEO 347.0 A
40VETO 347.0 A
40YETO 347.0 A
50HEDO 347.0 A
50HETO 347.0 A
Minimum rated capacity (20HR/IEC):
40VEO 40.0 Ah
40VETO 40.0 Ah
40YETO 40.0 Ah
50HEDO 40.0 Ah
50HETO 40.0 Ah

General information
5
NOTE:
Select a propeller which will allow the engine
to reach the middle or upper half of the oper-
ating range at full throttle with the maximum
boat load. If operating conditions such as
light boat loads then allow the engine r/min to
rise above the maximum recommended
range, reduce the throttle setting to maintain
the engine in the proper operating range.
For instructions on propeller removal and in-
stallation, see page 62.
EMU25760
Start-in-gear protection
Yamaha outboard motors affixed with the
pictured label 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 in neutral.
Always select neutral before starting the en-
gine.
1. Propeller diameter in inches
2. Propeller pitch in inches
3. Type of propeller (propeller mark)
1. Propeller diameter in inches
2. Propeller pitch in inches
3. Type of propeller (propeller mark)
ZMU04606
-
x
123
ZMU04607
-
x
123
1. Start-in-gear protection label
ZMU01713
1

6
Basic components
EMU25795
Main components
NOTE:
* May not be exactly as shown; also may not be included as standard equipment on all mod-
els.
40VMHO, 40YMHO, 50HMHO
1
2
3
4
5
6
7
16
8
9
10
11
12
13
14
15
ZMU03344
1. Manual starter handle
2. Tiller handle
3. Choke knob
4. Warning indicator
5. Tilt lock lever
6. Clamp screw
7. Trim rod
8. Cooling water inlet
9. Propeller
10. Trim tab (anode)
11. Anti-cavitation plate
12. Anode
13. Tilt support lever
14. Clamp bracket
15. Top cowling
16. Fuel tank*

Basic components
7
40VEO
7
8
9
10
11
12
13
14
1
15
16
2
3
4
5
6
ZMU03346
1. Oil tank filler cap
2. Warning indicator(s)
3. Tilt lock lever
4. Clamp screw
5. Trim rod
6. Battery cable
7. Propeller
8. Cooling water inlet
9. Trim tab (anode)
10. Anti-cavitation plate
11. Anode
12. Tilt support lever
13. Clamp bracket
14. Top cowling
15. Remote control box (side mount type)*
16. Fuel tank*

Basic components
8
40VETO, 40YETO, 50HEDO, 50HETO
EMU25802
Fuel tank
If your model was equipped with a portable
fuel tank, its function is as follows.
WARNING
EWM00020
The fuel tank supplied with this engine is
its dedicated fuel reservoir and must not
be used as a fuel storage container. Com-
mercial users should conform to relevant
licensing or approval authority regula-
tions.
113
14 15 16
17
2
3
4
6
5
7
8
4
9
10
11
12
ZMU04548
1. Oil tank filler cap
2. Warning indicator(s)
3. Battery cable
4. Anode(s)
5. Propeller
6. Cooling water inlet
7. Trim tab (anode)
8. Anti-cavitation plate
9. Trim rod
10. Clamp bracket
11. Tilt support lever
12. Top cowling
13. Remote control box (side mount type)*
14. Trim meter*
15. Tachometer*
16. Digital tachometer*
17. Fuel tank*

Basic components
9
EMU25830
Fuel joint
This joint is used to connect the fuel line.
EMU25841
Fuel gauge
This gauge is located on either the fuel tank
cap or on the fuel joint base. It shows the ap-
proximate amount of fuel remaining in the
tank.
EMU25850
Fuel tank cap
This cap seals the fuel tank. When removed,
the tank can be filled with fuel. To remove the
cap, turn it counterclockwise.
EMU25860
Air vent screw
This screw is on the fuel tank cap. To loosen
the screw, turn it counterclockwise.
EMU26180
Remote control
The remote control lever actuates both the
shifter and the throttle. The electrical switch-
es are mounted on the remote control box.
EMU26190
Remote control lever
Moving the lever forward from the neutral po-
sition engages forward gear. Pulling the le-
ver back from neutral engages reverse. The
engine will continue to run at idle until the le-
ver is moved about 35°(a detent can be felt).
Moving the lever farther opens the throttle,
and the engine will begin to accelerate.
1. Fuel joint
2. Fuel gauge
3. Fuel tank cap
4. Air vent screw
1. Fuel joint
2. Fuel gauge
3. Fuel tank cap
4. Air vent screw
ZMU02284
3
1
4
2
ZMU03157
13
42
1. Power trim and tilt switch
2. Remote control lever
3. Neutral interlock trigger
4. Neutral throttle lever
5. Main switch / choke switch
6. Engine stop lanyard switch
7. Throttle friction adjuster

Basic components
10
EMU26201
Neutral interlock trigger
To shift out of neutral, first pull the neutral in-
terlock trigger up.
EMU26211
Neutral throttle lever
To open the throttle without shifting into ei-
ther forward or reverse, put the remote con-
trol 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.
EMU25911
Tiller handle
To change direction, move the tiller handle to
the left or right as necessary.
EMU25922
Gear shift lever
Pulling the gear shift lever towards you puts
the engine in forward gear so that the boat
moves ahead. Pushing the lever away from
you puts the engine in reverse gear so that
the boat moves astern.
1. Neutral “”
2. Forward “”
3. Reverse “”
4. Shift
5. Fully closed
6. Throttle
7. Fully open
1. Neutral interlock trigger
1. Fully open
2. Fully closed
ZMU03348

Basic components
11
EMU25941
Throttle grip
The throttle grip is on the tiller handle. Turn
the grip counterclockwise to increase speed
and clockwise to decrease speed.
EMU25961
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.
EMU25970
Throttle friction adjuster
A friction device provides adjustable resis-
tance to movement of the throttle grip or the
remote control lever, and can be set accord-
ing to operator preference.
To increase resistance, turn the adjuster
clockwise. To decrease resistance, turn the
adjuster counterclockwise.
WARNING
EWM00030
Do not overtighten the friction adjuster. If
there is too much resistance, it could be
difficult to move throttle lever or grip,
which could result in an accident.
1. Forward “”
2. Neutral “”
3. Reverse “”
ZMU04916
13
2
FR
N
ZMU03350
1. Throttle indicator
ZMU03351
1
ZMU03095

Basic components
12
When constant speed is desired, tighten the
adjuster to maintain the desired throttle set-
ting.
EMU25990
Engine stop lanyard switch
The lock plate must be attached to the en-
gine 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 un-
der power.
WARNING
EWM00120
● Attach the engine stop switch lanyard
to a secure place on your clothing, or
your arm or leg while operating.
● Do not attach the lanyard to clothing
that could tear loose. Do not route the
lanyard where it could become entan-
gled, preventing it from functioning.
●
Avoid accidentally pulling the lanyard
during normal operation. Loss of en-
gine 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.
EMU26001
Engine stop button
To open the ignition circuit and stop the en-
gine, push this button.
ZMU03352
1. Lanyard
2. Lock plate
1. Lanyard
2. Lock plate
ZMU04712
2
1

Basic components
13
EMU26011
Choke knob for pull type
To supply the engine with the rich fuel mix-
ture required to start, pull out this knob.
EMU26070
Manual starter handle
To start the engine, first gently pull the han-
dle out until resistance is felt. From that posi-
tion, then pull the handle straight out quickly
to crank the engine.
EMU26090
Main switch
The main switch controls the ignition system;
its operation is described below.
●
“” (off)
With the main switch in the “”(off) posi-
tion, the electrical circuits are off, and the key
can be removed.
● “” (on)
With the main switch in the “”(on) posi-
tion, the electrical circuits are on, and the key
cannot be removed.
●
“” (start)
With the main switch in the “”(start) po-
sition, the starter motor turns to start the en-
gine. When the key is released, it returns
automatically to the “”(on) position.
EMU26110
Steering friction adjuster
A friction device provides adjustable resis-
tance to the steering mechanism, and can be
set according to operator preference. An ad-
juster lever is located on the bottom of the
tiller handle bracket.
To increase resistance, turn the lever to the
left.
To decrease resistance, turn the lever to the
right.
WARNING
EWM00040
Do not overtighten the friction adjuster. If
there is too much resistance, it could be
ZMU03354
ZMU03355
ZMU02942

Basic components
14
difficult to steer, which could result in an
accident.
EMU26122
Steering friction adjuster
A friction device provides adjustable resis-
tance to the steering mechanism, and can be
set according to operator preference. An ad-
justing screw or bolt is located on the swivel
bracket.
To increase resistance, turn the adjuster
clockwise.
To decrease resistance, turn the adjuster
counterclockwise.
WARNING
EWM00040
Do not overtighten the friction adjuster. If
there is too much resistance, it could be
difficult to steer, which could result in an
accident.
EMU26141
Power trim and tilt switch on remote
control or tiller handle
The power trim and tilt system adjusts the
outboard motor angle in relation to the tran-
som. Pressing the switch “”(up) trims the
outboard motor up, then tilts it up. Pressing
the switch “”(down) tilts the outboard mo-
tor down and trims it down. When the switch
is released, the outboard motor will stop in its
current position.
NOTE:
For instructions on using the power trim and
tilt switch, see pages 37 and 41.
EMU26151
Power trim and tilt switch on bottom
engine cowling
The power trim and tilt switch is located on
the side of the bottom engine cowling. Press-
ing the switch “”(up) trims the outboard
motor up, then tilts it up. Pressing the switch
“”(down) tilts the outboard motor down
and trims it down. When the switch is re-
leased, the outboard motor will stop in its
current position.
WARNING
EWM01030
Use the power trim and tilt switch located
on the bottom engine cowling only when
the boat is at a complete stop with the en-
gine off. Attempting to use this switch
ZMU03591
ZMU02908