Yamaha F 40 User Guide

							 
Basic components 
25 
 
Changing the display format 
 
Pressing the “” (mode) button chang-
es the display format in the following pat-
tern: 
 
Total hours 
→ 
Trip hours 
→ 
Display off 
 
Resetting the trip hours 
 
Simultaneously pressing the “” (set)
and “” (mode) buttons for more than
1 second while the trip hours are displayed
resets the trip counter to 0 (zero).
NOTE:
 
The total number of hours the engine has 
been run cannot be reset. 
EMU26801 
Warning system
CAUTION:
 
ECM00090  
Do not continue to operate the engine if a
warning device has activated. Consult
your Yamaha dealer if the problem can- 
not be located and corrected. 
EMU26816 
Overheat warning 
This engine has an overheat warning device.
If the engine temperature rises too high, the
warning device will activate. 
Activation of warning device 
 
The engine speed will automatically de-
crease to about 2000 r/min. 
 
If equipped with an overheat warning indi-cator, it will light or blink. 
 
The buzzer will sound (if equipped on the
tiller handle, remote control box, or main
switch panel).
If the warning system has activated, stop the
engine and check the cooling water inlet for
clogging.
ZMU01741
ZMU05028
ZMU04044 
						

							 
Basic components 
26 
EMU30167 
Low oil pressure warning 
If the oil pressure drops too low, the warning
device will activate. 
Activation of warning device 
 
The engine speed will automatically de-
crease to about 2000 r/min. 
 
If equipped with a low oil pressure warning
indicator, it will light or blink. 
 
The buzzer will sound (if equipped on the
tiller handle, remote control box, or mainswitch panel).
If the warning system has activated, stop the
engine as soon as it is safe to do so. Check
the oil level and add oil as needed. If the oil
level is correct and the warning device does
not switch off, consult your Yamaha dealer.
CAUTION:
 
ECM00100  
Do not continue to run the engine if the
low oil pressure warning indicator is on. 
Serious engine damage could occur.
ZMU04994
ZMU04105 
						

							 
27 
Operation 
EMU26901 
Installation
CAUTION:
 
ECM00110  
Incorrect engine height or obstructions
to smooth water flow (such as the design
or condition of the boat, or accessories
such as transom ladders or 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 ex-
haust housing is low enough to prevent wa-
ter entry into the powerhead, when water
rises due to waves when the outboard is not 
running. 
EMU26910 
Mounting the outboard motor
WARNING
 
EWM00820  
 
Overpowering a boat could cause se-
vere instability. Do not install an out-
board motor with more horsepower
than the maximum rating on the capac-
ity plate of the boat. If the boat does not
have a capacity plate, consult the boat
manufacturer. 
 
The information presented in this sec-
tion is intended as reference only. It is
not possible to provide complete in-
structions for every possible boat and
motor combination. Proper mounting
depends in part on experience and the 
specific boat and motor combination.
WARNING
 
EWM00830  
Improper mounting of the outboard mo-
tor could result in hazardous conditions
such as poor handling, loss of control, or
fire hazards. Observe the following: 
 
For permanently mounted models, your
dealer or other person experienced in
proper rigging should mount the motor.
If you are mounting the motor yourself,
you should be trained by an experi-
enced person. 
 
For portable models, your dealer or oth-
er person experienced in proper out-
board motor mounting should show 
you how to mount your motor. 
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. 
EMU26930 
Mounting height (boat bottom) 
To run your boat at optimum efficiency, the
water resistance (drag) of the boat and out-
board motor must be made as little as possi-
ble. The mounting height of the outboard 
1. Center line (keel line)
ZMU017601 
						

							 
Operation 
28 
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 en-
gine to overheat. If the mounting height is too
low, the water resistance will increase and
thereby reduce engine efficiency. Mount the
outboard motor so that the anti-cavitation
plate is in alignment with the bottom of the
boat.
NOTE:
 
 
The optimum mounting height of the out-
board motor is affected by the boat/motor
combination and the desired use. Test
runs at different heights can help deter-
mine the optimum mounting height. Con-
sult your Yamaha dealer or boat
manufacturer for further information on de-
termining the proper mounting height. 
 
For instructions on setting the trim angle of 
the outboard motor, see page 39. 
EMU30173 
Breaking in engine 
Your new engine requires a period of break-
in to allow mating surfaces of moving parts to
wear in evenly. Correct break-in will help en-
sure proper performance and longer enginelife.
CAUTION:
 
ECM00800  
Failure to follow the break-in procedure
could result in reduced engine life or 
even severe engine damage. 
EMU27081 
Procedure for 4-stroke models 
Run the engine under load (in gear with a
propeller installed) for 10 hours as follows.
1. First hour:
Run the engine at 2000 r/min or at ap-
proximately half throttle.
2. Second hour:
Run the engine at 3000 r/min or at ap-
proximately three-quarter throttle.
3. Remaining eight hours:
Run the engine at any speed. However,
avoid operating at full throttle for more
than 5 minutes at a time.
4. After the first 10 hours:
Operate the engine normally. 
EMU27103 
Preoperation checks
WARNING
 
EWM00080  
If any item in the preoperation check is
not working properly, have it inspected
and repaired before operating the out-
board motor. Otherwise an accident 
could occur.
CAUTION:
 
ECM00120  
Do not start the engine out of water. Over-
heating and serious engine damage can 
occur. 
EMU27111 
Fuel 
 
Check to be sure you have plenty of fuel
for your trip. 
 
Make sure there are no fuel leaks or gaso-
ZMU01762 
						

							 
Operation 
29 
line fumes. 
 
Check fuel line connections to be sure they
are tight (if equipped Yamaha fuel tank or
boat tank). 
 
Be sure the fuel tank is positioned on a se-
cure, flat surface, and that the fuel line is
not twisted or flattened, or likely to contact
sharp objects (if equipped Yamaha fuel
tank or boat tank). 
EMU27130 
Controls 
 
Check throttle, shift, and steering for prop-
er operation before starting the engine. 
 
The controls should work smoothly, with-
out binding or unusual free play. 
 
Look for loose or damaged connections. 
 
Check operation of the starter and stop
switches when the outboard motor is in the
water. 
EMU27140 
Engine 
 
Check the engine and engine mounting. 
 
Look for loose or damaged fasteners. 
 
Check the propeller for damage. 
EMU27163 
Checking the engine oil level 
1. Put the outboard motor in an upright po-
sition (not tilted).
2. Remove oil dipstick and wipe it clean.
3. Completely insert the dipstick and re-
move it again.
4. Check the oil level using the dipstick to
be sure the level falls between the upper
and lower marks. Fill with oil if it is below
the lower mark, or drain to the specified
level if it is above the upper mark.
NOTE:
 
Be sure to completely insert the dipstick into 
the dipstick guide. 
EMU27433 
Filling fuel
WARNING
 
EWM00060  
Gasoline and its vapors are highly flam-
mable and explosive. Keep away from
sparks, cigarettes, flames, or other 
sources of ignition. 
1. Remove the fuel tank cap.
2. Carefully fill the fuel tank.
3. Securely close the cap after filling the 
1. Oil dipstick
1. Lower level mark
2. Oil dipstick
3. Upper level mark
1
ZMU04046
ZMU02082
1
3
2 
						

							 
Operation 
30 
tank. Wipe up any spilled fuel. 
EMU27270 
Ring Free Fuel Additive 
Gasoline is a precise blend of many different
substances, each chosen to give certain
characteristics. Gasoline blends have been
changing in recent years in response to con-
cerns about pollution and resulting emis-
sions regulations. One of the most obvious
changes has been the elimination of lead
from most fuels.
As gasoline has changed, the amount of ad-
ditives such as aromatics and oxygenates
has increased. These additives are impor-
tant for the engines in passenger cars, but
they can have detrimental effects in marine
engines, because of increased deposits in
the combustion chamber. When enough de-
posits collect, piston rings begin sticking.
Performance drops and engine wear in-
creases dramatically.
While many additives available may reduce
deposits, Yamaha recommends the use of 
Ring Free Fuel Additive 
, available from
your Yamaha dealer.  
Ring Free Fuel Addi-
tive 
 has repeatedly proven its ability to clean
combustion deposits from inside the engine,
notably the critical piston-ring-land area, andfuel system components. Follow product la-
beling for use instructions. 
EMU27450 
Operating engine 
EMU27461 
Feeding fuel (portable tank)
WARNING
 
EWM00420  
 
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. 
 
When the air vent screw is loosened,
gasoline vapor will be released. Gaso-
line is highly flammable, and its vapors
are flammable and explosive. Refrain
from smoking, and keep away from
open flames and sparks while loosen-
ing the air vent screw. 
 
This product emits exhaust gases
which contain carbon monoxide, a col-
orless, odorless gas which could cause
brain damage or death when inhaled.
Symptoms include nausea, dizziness,
and drowsiness. Keep cockpit and cab-
in areas well ventilated. Avoid blocking 
exhaust outlets. 
1. If there is an air vent screw on the fuel
tank cap, loosen it 2 or 3 turns.
2. If there is a fuel joint on the motor, firmly Fuel tank capacity:
25 L (6.60 US gal) (5.50 Imp.gal)
ZMU04047
ZMU02022 
						

							 
Operation 
31 
connect the fuel line to the joint. Then
firmly connect the other end of the fuel
line to the joint on the fuel tank.
3. If a steering friction adjuster is provided
on your outboard motor, securely attach
the fuel line to the fuel line clamp.
NOTE:
 
During engine operation place the tank hori-
zontally, otherwise fuel cannot be drawn 
from the fuel tank.
4. Squeeze the primer pump with the outlet
end up until you feel it become firm. 
EMU27490 
Starting engine 
EMU27541 
Starting engine 
1. Place the gear shift lever in neutral.
NOTE:
 
The start-in-gear protection device prevents
the engine from starting except when in neu- 
tral.
2. 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 into the en-
gine stop switch.
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
ZMU04048
ZMU02024
ZMU02025 
						

							 
Operation 
32 
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. 
3. Place the throttle grip in the “”
(start) position.
4. Pull the manual starter handle slowly un-
til you feel resistance. Then give a
strong pull straight out to crank and start
the engine. Repeat if necessary.5. After the engine starts, slowly return the
manual starter handle to its original po-
sition before releasing it.
NOTE:
 
 
When the engine is cold, it needs to be
warmed up. For further information, see
page 35. 
 
If the engine is warm and fails to start,
open the throttle slightly and try to start the
engine again. If the engine still fails to 
start, see page 70. 
EMU27592 
Electric start / prime start models 
1. Place the gear shift lever in neutral.
NOTE:
 
The start-in-gear protection device prevents
the engine from starting except when in neu- 
tral.
2. Attach the engine stop switch lanyard to
a secure place on your clothing, or your
ZMU04050 
						

							 
Operation 
33 
arm or leg. Then install the lock plate on
the other end of the lanyard into the en-
gine stop switch.
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. 
3. Place the throttle grip in the “”
(start) position. After the engine starts,
return the throttle to the fully closed po-
sition.4. Turn the main switch to “” (start),
and hold it for a maximum of 5 seconds.
5. Immediately after the engine starts, re-
lease the main switch and allow it to re-
turn to “” (on).
CAUTION:
 
ECM00191  
 
Never turn the main switch to “”
(start) while the engine is running. 
 
Do not keep the starter motor turning
for more than 5 seconds. If the starter
motor is turned continuously for more
than 5 seconds, the battery will be
quickly discharged, thus making it im-
possible to start the engine. The starter
can also be damaged. If the engine will
not start after 5 seconds of cranking,
return the main switch to “” (on), wait
10 seconds, then crank the engine 
again. 
						

							 
Operation 
34
NOTE:
 
 
When the engine is cold, it needs to be
warmed up. For further information, see
page 35. 
 
If the engine is warm and fails to start,
open the throttle slightly and try to start the
engine again. If the engine still fails to 
start, see page 70. 
EMU27662 
Electric start and remote control models 
1. Place the remote control lever in neutral.
NOTE:
 
The start-in-gear protection device prevents
the engine from starting except when in neu- 
tral.
2. 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 into the en-
gine stop switch.
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 lanyardduring 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. 
3. Turn the main switch to “” (on).
4. Turn the main switch to “” (start),
and hold it for a maximum of 5 seconds.
5. Immediately after the engine starts, re-
lease the main switch and allow it to re-
turn to “” (on).
CAUTION:
 
ECM00191  
 
Never turn the main switch to “”
(start) while the engine is running. 
 
Do not keep the starter motor turning
for more than 5 seconds. If the starter
motor is turned continuously for more
than 5 seconds, the battery will be