Yamaha C40 Manual

 
Operation 
26 
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 en-
gine speed occasionally.
5. After the first 10 hours:
Operate the engine normally. Use only
straight gasoline in the fuel tank. The
Yamaha oil injection system provides
proper lubrication for normal operation. 
EMU27102 
Preoperation checks
WARNING
 
EWM00080  
If any item in the preoperation check is
not working properly, have...

 
Operation 
27
CAUTION:
 
ECM00130  
Be sure to take the above steps when op-
erating the engine after a long period of
storage. Otherwise engine seizure could 
occur. 
EMU27233 
Filling fuel and engine oil 
EMU27242 
Filling fuel for portable tank
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. Fill the fuel tank carefully.
3. Close the cap securely after...

 
Operation 
28 
EMU27311 
Filling oil for electric start models
WARNING
 
EWM00530  
Do not add gasoline into the oil tank. Fire 
or explosion could result. 
This engine uses the Yamaha oil injection
system, which provides superior lubrication
by ensuring the proper oil ratio for all operat-
ing conditions. No fuel premixing is needed.
Simply pour gasoline into the fuel tank and
oil into the oil tank. Convenient indicator seg-
ments indicate the status of the oil supply.
For details on reading the...

 
Operation 
29 
EMU27321 
Oil level indicator operation 
The various functions of the oil level system are as follows: 
EMU27350 
Electric start models 
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...

 
Operation 
30 
tank cap, loosen it 2 or 3 turns.
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.
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...

 
Operation 
31 
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...

 
Operation 
32 
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...

 
Operation 
33 
again.
NOTE:
 
 
When the engine is cold, it needs to be
warmed up. For further information, see
page 33. 
 
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 60. 
EMU27670 
Warming up engine 
EMU27702 
Electric start and prime start models 
1. After starting the engine, allow it to idle
for 3 minutes to warm up. Failure to do
so will shorten engine life.
2. Check for a steady flow of...

 
Operation 
34 
firmly from neutral to forward.
Remote control models
1. Pull up the neutral interlock trigger (if
equipped) and move the remote control
lever quickly and firmly from neutral to
forward.
 
EMU27784 
Reverse (automatic reverse lock and 
power trim and tilt models)
WARNING
 
EWM00190  
When operating in reverse, go slowly. Do
not open the throttle more than half. Oth-
erwise the boat could become unstable,
which could result in loss of control and 
an accident. 
Tiller control models
1....

 
Operation 
35 
ping the engine immediately after operating
at high speed is not recommended. 
EMU27844 
Procedure 
1. Push and hold the engine stop button or
turn the main switch to “” (off).
2. After stopping the engine, disconnect
the fuel line if there is a fuel joint on the
outboard motor.
3. Tighten the air vent screw on the fuel
tank cap (if 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...