Yamaha F 40 User Guide

 
Maintenance 
55 
Yamaha genuine parts and accessories are
available from your Yamaha dealer. 

 
Maintenance 
56 
EMU28522 
Maintenance chart 
Frequency of maintenance operations may be adjusted according to the operating condi-
tions, but the following table gives general guidelines. Refer to the sections in this chapter for
explanations of each owner-specific action.
NOTE:
 
When operating in salt water, turbid or muddy water, the engine should be flushed with clean 
water after each use.
The “” symbol indicates the check-ups which you may carry out yourself.
The “” symbol indicates work to be...

 
Maintenance 
57 
EMU28874 
Maintenance chart (additional) 
EMU28910
NOTE:
 
When using lead or high-sulfur gasoline, inspecting valve clearance may be required more 
frequently than every 500 hours. 
Water pumpInspection / replace-
ment
Engine oil Inspection / change
Oil filter (cartridge) Change
Spark plug(s)Cleaning / adjustment / 
replacement
Timing beltInspection / replace-
ment
Valve clearance (OHC, 
OHV)Inspection / adjustment 
Item ActionsEvery
500 hours (2.5 years) 1000 hours (5 years) 
Timing...

 
Maintenance 
58 
EMU28931 
Greasing 
Yamaha marine grease (Water resistant grease) 
F40 
EMU28952 
Cleaning and adjusting spark plug
WARNING
 
EWM00560  
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 com-
ponent and is easy to inspect. The condition
of the spark plug can indicate something
about the condition of the engine. For exam-
ple, if...

 
Maintenance 
59 
adjust the gap to specification if necessary.
When fitting the plug, always clean the gas-
ket surface and use a new gasket. Wipe off
any dirt from the threads and screw in the
spark plug to the correct torque.
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 fin-
ger-tight. Have the spark plug adjusted to the
correct torque as soon as possible with a 
torque-wrench. 
EMU28962 
Checking fuel...

 
Maintenance 
60 
EMU28990 
Checking fuel filter 
Check the fuel filter periodically. The fuel fil-
ter is a one piece, disposable type. If foreign
matter is found in the filter, replace it. For re-
placement of the fuel filter, consult your
Yamaha dealer. 
EMU29041 
Inspecting idling speed
WARNING
 
EWM00451  
 
Do not touch or remove electrical parts
when starting or during operation. 
 
Keep hands, hair, and clothes away
from the flywheel and other rotating 
parts while the engine is running....

 
Maintenance 
61
NOTE:
 
Change the engine oil when the oil is still 
warm.
1. Put the outboard motor in an upright po-
sition (not tilted).
2. Prepare a suitable container that holds a
larger amount than the engine oil capac-
ity. Loosen and remove the drain screw
while holding the container under the
drain hole. Then remove the oil filler cap.
Let the oil drain completely. Wipe up any
spilled oil immediately.
3. Put a new gasket on the oil drain screw.
Apply a light coat of oil to the gasket and...

 
Maintenance 
62 
not be located and corrected. 
6. Turn off the engine and wait 3 minutes.
Recheck the oil level using the dipstick
to be sure the level falls between the up-
per 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.
7. Dispose of used oil according to local
regulations.
NOTE:
 
 
For more information on the disposal of
used oil, consult your Yamaha dealer. 
 
Change the oil more often when operating
the engine...

 
Maintenance 
63 
2. Operate each of the power trim and tilt
switches / power tilt switches to check
that all switches work.
3. Tilt the outboard motor up and check
that the trim and tilt rod / the tilt rod is
pushed out completely.
4. Check that the trim and tilt rod / the tilt
rod is free of corrosion or other flaws.
5. Tilt the outboard motor down. Check
that the trim and tilt rod / the tilt rod oper-
ates smoothly.
NOTE:
 
Consult your Yamaha dealer if any operation 
is abnormal. 
EMU29171 
Checking...

 
Maintenance 
64 
 
Check the propeller shaft oil seal for dam-
age.
NOTE:
 
If the shear pin equipped: it is designed to
break if the propeller hits a hard underwater
obstacle to help protect the propeller and
drive mechanism. The propeller will then
spin freely on the shaft. If this happens, the 
shear pin must be replaced. 
EMU30660 
Removing the propeller 
EMU29194 
Spline models 
1. Straighten the cotter pin and pull it out
using a pair of pliers.
2. Remove the propeller nut, washer, and
spacer...