engine YAMAHA FX HO 2021 Repair Manual

Care and storage
87
ter flows out continually from the jet
thrust nozzle.
(8) Run the engine at idling speed for about 3 minutes watching the engine condition.
If the engine stops while flushing, turn
the water supply off immediately and
perform the procedure again from step 7.
NOTICE: Do not supply water to the
cooling water passages when the en-
gine is not running. The water could
flow back through the muffler into the
engine, causing severe engine dam-
age.
[ECJ00123]
(9) Turn the water supply off.
(10) Discharge the remaining water out of the cooling water passages by alternately
squeezing and releasing the throttle lever
quickly for 10 to 15 seconds.
(11) Stop the engine.
(12) Remove the garden hose adapter, and then securely install the flushing hose
connector cap by tightening it until it
stops.
(13) Securely close the stern storage com- partment.
(14) Securely install the removable watertight storage compartment and seats in their
original positions.
EJU33736Cleaning the watercraft
(1) Remove the seats. (See page 49 for seatremoval and installation procedures.) (2) Rinse the engine and engine compart-
ment with a small amount of water.
NOTICE: Do not use high-pressure
water when rinsing the engine or en-
gine compartment as severe engine
damage could result.
[ECJ00572]
(3) Drain the water from the engine com- partment. (See page 61 for information
on draining the bilge water.)
(4) Wipe the engine and engine compart- ment with a dry cloth.
(5) Wash down the hull, deck, and jet pump with fresh water.
(6) Wipe the hull, deck, and jet pump with a dry cloth.
(7) Wipe all vinyl and rubber components, such as the seats and engine compart-
ment seals, with a vinyl protectant.
(8) To minimize corrosion, spray metallic parts of the hull, deck, and engine with a
rust inhibitor.
(9) Allow the engine compartment to air dry completely before installing the seats.
(10) Securely install the seats in their original positions.
EJU3368ABattery care
If the watercraft will not be used for more than
a month, remove the battery from the water-
craft, check it, and then store it in a cool, dry
place.
EWJ00792
Battery electrolyte is poisonous and dan-
gerous, causing severe burns, etc. Elec-
trolyte contains sulfuric acid. Avoid
contact with skin, eyes, or clothing.
Antidotes
External: Flush with water.
Internal: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten
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Care and storage
89
(4) Store the battery in a cool, dry place.NOTICE: Storing the battery in an un-
charged condition can cause perma-
nent battery damage. Check the
battery periodically.
[ECJ00103]
To install the battery:
(1) Place the battery in the battery compart- ment and hook the battery bands onto
the holders.
(2) Connect the positive (+) battery lead (red) to the positive (+) battery terminal.
NOTICE: Reversal of the battery leads
will damage the electrical parts.
[ECJ00262]
(3) Connect the negative (–) battery lead (black) to the negative (–) battery termi-
nal.
(4) Make sure that the battery is securely held in place.
EJU33493
Long-term storageEWJ00331
Always place the watercraft upright in a
horizontal position when storing it, other-
wise fuel could leak out into the engine or
engine compartment, which could create
a fire hazard.
Storage for long periods of time, such as win-
ter storage, requires preventive maintenance
to ensure against deterioration. It is advisable
to have the watercraft serviced by a Yamaha
dealer prior to storage.
However, the following procedures can be
performed easily by the owner.
EJU40763Cleaning
(1) Flush the cooling water passages. (See
page 86 for information on flushing the
cooling water passages.)
TIP:
If you will be storing the watercraft for a pro-
longed period, such as winter storage, top off
the fuel tank with fresh gasoline and add fuel
stabilizer and conditioner to the fuel tank ac-
cording to the manufacturer’s instruction be-
fore starting the engine.
(2) Clean the watercraft. (See page 87 for in-formation on cleaning the watercraft.)
Wax the hull with a non-abrasive wax.
EJU44741Lubrication
To keep moving parts sliding or rotating
smoothly, lubricate them with water-resistant
grease.
Recommended water-resistant grease:
YAMALUBE MARINE
GREASE/Yamaha Grease A
Recommended water-resistant grease:YAMALUBE MARINE GREASE /
Ya m a h a G r e a s e A
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Care and storage
90
Steering cable (jet thrust nozzle end), elec-
tric trim rod (jet thrust nozzle end), and ball
joint
TIP:
Disconnect the electric trim rod from the ball
joint before lubricating.
Shift rod (reverse gate end) and ball joint
TIP:
Disconnect the shift rod from the ball joint be-
fore lubricating.
EJU40812Rustproofing
Spray metallic parts of the hull, deck, and en-
gine with a rust inhibitor.
Have a Yamaha dealer rustproof the internal
engine components.
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Maintenance
91
EJU33769
Maintenance
Periodic checks and lubrication will keep
your watercraft in the safest and most effi-
cient condition possible. Therefore, make
sure to carry out the periodic maintenance.
Safety is an obligation of the watercraft own-
er. Proper maintenance must be carried out
to keep the exhaust emission and sound lev-
els within the regulated limits. The most im-
portant points of watercraft inspection and
lubrication are explained on the following pa-
ges.
See a Yamaha dealer for genuine Yamaha re-
placement parts and optional accessories
designed for your watercraft.
Remember, failures that are the result of the
installation of parts or accessories which are
not qualitatively equivalent to genuine
Yamaha parts are not covered by the limited warranty.
Maintenance, replacement, or repair of
the emission control devices and system
may be performed by any marine SI engine
repair establishment or individual. War-
ranty repair, however, must be performed
at an authorized Yamaha marine dealer-
ship.
EWJ00312
Be sure to turn off the engine when you
perform maintenance unless otherwise
specified. If you are not familiar with ma-
chine servicing, this work should be done
by a Yamaha dealer or other qualified me-
chanic.
EJU42023Removing and installing the engine
cover
The engine cover is removable. To remove the engine cover:
(1) Remove the seats. (See page 49 for seat
removal and installation procedures.)
(2) Remove the engine cover screws.
(3) Lift up the engine cover to remove it.
To install the engine cover:
(1) Place the engine cover in its original po- sition, and then push it down.
(2) Install the engine cover screws.
1 Engine cover screw
1 Engine cover
1
1
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Maintenance
93
EJU43101Periodic maintenance chart
The periodic maintenance chart gives general guidelines for periodic maintenance. Have a
Yamaha dealer perform the checks in the following chart. However, maintenance may need to be performed more frequently depending on your operating conditions. If you have any
questions, consult a Yamaha dealer.
This “ √” mark indicates items to be checked and serviced by a Yamaha dealer.
Item OperationInitial Thereafter every
Page
10 hours 50 hours
or 12
months *1 100
hours or 12
months *1 200
hours or 24
months *1
Fuel line Check fuel hoses and
clamps
√
—
Fuel filler cap/Wa-
ter separator Check O-rings for cracks
and deformation
√
—
Fuel tank Check installation and
straps
√
—
Water inlet strainer Check for clogs and dam-
age
√
—
Cooling water hos-
es Check for damage and
leakage, and check
clamps
√
—
Engine oil Replace √√ 95
Oil filter Replace √95
Intermediate hous-
ing Lubricate
√—
Spark plugs Check √√ —
Battery Check state of charge,
terminals and bands
√
—
Battery leads Check terminals √—
Steering master Check operation and for
looseness
√√
—
Steering cable Check exterior and con-
nections, and lubricate
√
—
Electric trim rod Check exterior and con-
nections, and lubricate
√
—
Shift rod and re-
verse gate Check exterior and con-
nections, and lubricate
√
—
Air filter element Check for damage and
dirt
√
—
Air intake hoses Check for damage, and
check clamps
√
—
Thr

ottle body Lubricate throttle valve √—
UF3V72E0.book Page 93 Tuesday, June 16, 2020 2:29 PM

Maintenance
94
*1: Whichever comes first.
*2: Check every 200 hours.
Perform the pre-operation checks and post-operation checks before performing periodic
maintenance.
Exhaust systemCheck for exhaust leak-
age, and check hoses and
clamps √
—
Breather hose Check breather hose and
clamps
√
—
Impeller Check for bends, dam-
age, and foreign material
√
—
Jet thrust nozzle Check movement, and lu-
bricate
√
—
Jet vacuum bilge Check hoses for clogs
and damage, check
clamps, and clean bilge
strainer
√
—
Stern drain plugs Check O-rings √—
Anode Check for corrosion, and
clean
√
*2 —
Valve clearance Check and adjust √ *2 —
Rubber coupling Check for cracks, inden-
tations, looseness, and
noise √
—
Engine mount Check for damage and
peeling
√
—
Item Operation
Initial Thereafter every
Page
10 hours 50 hours
or 12
months *1 100
hours or 12
months *1 200
hours or 24
months *1
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Maintenance
95
EJU36943Engine oil and oil filterEWJ00341
Engine oil is extremely hot immediately af-
ter the engine is turned off. Coming in con-
tact with or getting any engine oil on your
clothes could result in burns.
ECJ00992
Do not run the engine with too much or not
enough oil in the engine, otherwise the en-
gine could be damaged.
It is recommended to have a Yamaha dealer
change the engine oil and the engine oil filter.
However, if you choose to change the oil and
filter on your own, consult a Yamaha dealer.
UF3V72E0.book Page 95 Tuesday, June 16, 2020 2:29 PM

Specifications
96
EJU45442
Specifications
Watercraft capacity:
Maximum people on board:3 person
Maximum load capacity: 240 kg (530 lb)
Dimensions and weight:
Length:
3.58 m (140.9 in)
Width: 1.27 m (50.0 in)
Height: 1.23 m (48.4 in)
Dry weight: 379 kg (836 lb) (FX HO)
380 kg (838 lb) (FX CRUISER HO)
Performance:
Maximum output (according to ISO 8665/SAE
J1228):125.0 kW at 7600 r/min
Maximum fuel consumption:
49.7 L/h (13.1 US gal/h, 10.9 Imp.gal/h)
Cruising range at full throttle: 1.41 hour
Trolling speed: 1300 ±100 r/min
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Number of cylinders: 4
Engine displacement:
1812 cm³
Bore × stroke:
86.0 × 78.0 mm (3.39 × 3.07 in)
Compression ratio: 11.0 : 1
Valve clearance-intake (cold):
0.14–0.23 mm (0.0055–0.0091 in)
Valve clearance-exhaust (cold): 0.28–0.37 mm (0.0110–0.0146 in)
Lubrication system: Wet sump
Cooling system:
Water
Starting system: Electric Ignition system:
T.C.I.
Spark plug (NGK): LFR6A
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Battery capacity: 12 V, 18 Ah
Battery type: YTX20L-BS
Charging system:
Flywheel magneto
Drive unit:
Propulsion system:Jet pump
Jet pump type: Axial flow, single stage
Impeller rotation:
Counterclockwise
Jet thrust nozzle angle: 24+24 °
Jet thrust nozzle trim angle: -5, -3, 0, 3, 6 °
Fuel and oil:
Recommended fuel:Regular unleaded gasoline
Minimum octane rating (PON): 86
Minimum octane rating (RON):
90
Recommended engine oil: YAMALUBE 4W or 4-stroke motor oil
Recommended engine oil type SAE: SAE 10W-30, 10W-40, 20W-40, 20W-50
Recommended engine oil grade API:
API SG, SH, SJ, SL
Fuel tank total capacity: 70 L (18.5 US gal, 15.4 Imp.gal)
Engine oil quantity with oil filter replacement: 3.7 L (3.91 US qt, 3.26 Imp.qt)
Engine oil quantity without oil filter replacement:
3.5 L (3.70 US qt, 3.08 Imp.qt)
Engine oil total quantity: 5.3 L (5.60 US qt, 4.66 Imp.qt)
UF3V72E0.book Page 96 Tuesday, June 16, 2020 2:29 PM

Trouble recovery
97
EJU34562
Troubleshooting
If you have any trouble with your watercraft, use the troubleshooting chart to check for the
possible cause.
If you cannot find the cause, consult a Yamaha dealer.
EJU45320Troubleshooting chart
Confirm the possible cause and remedy, and then refer to the applicable page.
TROUBLEPOSSIBLE CAUSE REMEDYPAGE
Engine does not
start (Starter motor
does not turn over) Ya m a h a S e -
curity System
Lock mode selected Select unlock mode
25
Engine shut-
off switch Clip not in place Install clip
26
Fuse Burned out Replace fuse and
check wiring 102
Battery Run down Recharge87
Poor terminal con-
nections Tighten as required
87
Terminal corroded Clean or replace 87
Starter motor Faulty Have serviced by
Yamaha dealer —
Engine does not
start (Starter motor
turns over) Throttle lever Squeezed
Release26
Faulty Have serviced by
Yamaha dealer —
RiDE lever Squeezed Release26
Faulty Have serviced by
Yamaha dealer —
Fuel Fuel tank empty Refill as soon as pos-
sible 57
Stale or contaminat-
ed Have serviced by
Yamaha dealer
—
Fuel tank Water or dirt present Have serviced by Yamaha dealer—
Spark plug Fouled or defective Have serviced by Yamaha dealer—
Fuel injec-
tion system Fuel pump faulty Have serviced by
Yamaha dealer —
UF3V72E0.book Page 97 Tuesday, June 16, 2020 2:29 PM

Trouble recovery
98
Engine runs irregu-
larly or stallsFuel Fuel tank empty Refill as soon as pos-
sible57
Stale or contaminat-
ed Have serviced by
Yamaha dealer
—
Fuel tank Water or dirt present Have serviced by Yamaha dealer—
Spark plug Fouled or defective Have serviced by Yamaha dealer—
Incorrect heat range Have serviced by Yamaha dealer —
Gap incorrect Have serviced by Yamaha dealer —
Electrical wir-
ing Loose connection Have serviced by
Yamaha dealer —
Fuel injec-
tion system Faulty or clogged in-
jectors Have serviced by
Yamaha dealer
—
Warning is dis-
played Fuel level
warningFuel tank empty Refill as soon as pos-
sible 57
Oil pressure
warning Oil pressure dropped Have serviced by
Yamaha dealer 48
Engine over-
heat warning Jet intake clogged Clean
100
Check en-
gine warning Faulty sensors Have serviced by
Yamaha dealer 47
TROUBLE POSSIBLE CAUSE REMEDY PAGE
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