Yamaha F150 Four Stroke Manual

Basic components
24
NOTE:
If twin engines are installed on your boat, the
gauge will only display the total fuel economy
of both engines.
NOTE:

Fuel consumption varies greatly with boat
design, weight, propeller used, engine trim
angle, sea conditions (including wind), and
throttle position. Fuel consumption also var-
ies slightly with the type of water (salt, fresh,
and contaminate levels), air temperature
and humidity, cleanliness of the boat bot-
tom, engine mounting height, skill of the op-
erator,...

Basic components
25
NOTE:
If the two engines’ speeds are not synchro-
nized while cruising, they can be synchro-
nized by adjusting trim angle or throttle.
EMU26791Water separator warning indicator
This indicator will blink when water has accu-
mulated in the water separator. In such an
event, stop the engine and drain the water
from the separator.
NOTE:
This indicator only operates when a water
separator sensor is equipped.
EMU26801
Warning system
CAUTION:
ECM00090
Do not continue to operate the engine...

Basic components
26
Should the overheat warning system of one
engine activate, the engine will slow down
and the buzzer will sound. This will cause the
other engine to slow down and the buzzer to
sound. To switch off the warning activation on
the engine not affected by overheating, turn
off the main switch of the engine overheating.
EMU26854Low 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-...

Operation
27
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 trans-
ducers) can create airborne water spray
while the boat is cruising. Severe engine
damage may result if the motor is operat-
ed continuously in the presence of air-
borne water spray.
NOTE:
During water testing check the buoyancy of
the boat, at rest, with its maximum load.
Check that...

Operation
28
EMU26930Mounting 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
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...

Operation
29
EMU27102
Preoperation checks
WARNING
EWM00080
If any item in the preoperation check is not
working properly, have it inspected and
repaired before operating the outboard
motor. Otherwise an accident could occur.
CAUTION:
ECM00120
Do not start the engine out of water. Over-
heating and serious engine damage can
occur.
EMU27111Fuel

Check to be sure you have plenty of fuel for
your trip.

Make sure there are no fuel leaks or gaso-
line fumes.

Check fuel line connections to be sure they
are...

Operation
30
3. Securely close the cap after filling the
tank. Wipe up any spilled fuel.
EMU27270Ring Free Fuel Additive
Gasoline is a precise blend of many different
substances, each chosen to give certain char-
acteristics. Gasoline blends have been
changing in recent years in response to con-
cerns about pollution and resulting emissions
regulations. One of the most obvious changes
has been the elimination of lead from most fu-
els.
As gasoline has changed, the amount of addi-
tives such as aromatics...

Operation
31
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...

Operation
32
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 to return it 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 dis-
charged, thus making it impossible to
start the engine. The starter can...

Operation
33
hole is blocked. Consult your Yamaha
dealer if the problem cannot be located
and corrected.

If the cooling passage is frozen, it may
take awhile for water to start flowing out
of the pilot hole.
EMU27740
Shifting
WARNING
EWM00180
Before shifting, make sure there are no
swimmers or obstacles in the water near
you.
CAUTION:
ECM00220
To change the boat direction or shifting
position from forward to reverse or vice-
versa, first close the throttle so that the en-
gine idles (or runs at low...