Yamaha F15 Owners Manual

 
Maintenance 
55 
2. Screw the garden hose connector onto a
garden hose which is connected to a
fresh water supply.
3. With the engine off, turn on the water tap
and let the water flush through the cool-
ing passages for about 15 minutes. Turn
off the water and disconnect the garden
hose.
4. When flushing is complete, reinstall the
garden hose connector on the fitting on
the bottom cowling. Tighten the connec-
tor securely.
CAUTION:
 
ECM00540  
Do not leave the garden hose connector
loose on the bottom...

 
Maintenance 
56 
EMU28486 
Periodic maintenance
WARNING
 
EWM01070  
Be sure to turn off the engine when you
perform maintenance unless otherwise
specified. If you or the owner is not famil-
iar with machine servicing, this work
should be done by your Yamaha dealer or 
other qualified mechanic.
Maintenance, replacement, or repair of
the emission control devices and sys-
tems may be performed by any marine
engine repair establishment or individual.
All warranty repairs, however, including
those to the...

 
Maintenance 
57 
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 
58 
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 
59 
EMU28931 
Greasing 
Yamaha marine grease (Water resistant grease) 
F9.9ER, T9.9ER, F15PR
ZMU02330 

 
Maintenance 
60 
F9.9MH, T9.9EH, F15MH, F15EH, F15PH
ZMU02331 

 
Maintenance 
61 
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 the center electrode porcelain is very
white, this could indicate an...

 
Maintenance 
62 
sources of ignition.
WARNING
 
EWM00910  
Leaking fuel can result in fire or explo-
sion. 
 
Check for fuel leakage regularly. 
 
If any fuel leakage is found, the fuel
system must be repaired by a qualified
mechanic. Improper repairs can make 
the outboard unsafe to operate. 
Check the fuel lines for leaks, crack, or mal-
function. If a problem is found, your Yamaha
dealer or other qualified mechanic should re-
pair it immediately.
Checkpoints 
 
Fuel system parts leakage 
 
Fuel...

 
Maintenance 
63 
2. Unscrew the filter cup, catching any
spilled fuel in a rag.
3. Remove the filter element, and wash it in
solvent. Allow it to dry. Inspect the filter
element and O-ring to make sure they
are in good condition. Replace them if
necessary. If any water is found in the
fuel, the Yamaha portable fuel tank or
other fuel tanks should be checked and
cleaned.
4. Reinstall the filter element in the cup.
Make sure the O-ring is in position in the
cup. Firmly screw the cup onto the filter...

 
Maintenance 
64 
stand.
CAUTION:
 
ECM00970  
 
Do not overfill the oil, and be sure the
outboard motor is upright (not tilted)
when checking and changing the en-
gine oil. 
 
If the oil level is above the upper level
mark, drain until the level meets the
specified capacity. Overfilling the oil 
could cause leakage or damage.
CAUTION:
 
ECM01240  
Change the engine oil after the first 10
hours of operation, and every 100 hours
or at 6-month intervals thereafter. Other- 
wise the engine will wear...