2018 YAMAHA SUPERJET overheating

Control function operation
22
proper operation of the cooling system, make
sure that water is being discharged from the
cooling water pilot outlet. If water is not being
discharged from the outlet, stop the engine
and check the jet intake for clogging. (See
page 66 for information on the jet intake.)
TIP:
It will take about 20 seconds for the water
to reach the outlet after the engine is start-
ed.
Water discharge may not be constant
when the engine is running at idling speed.
If this occurs, apply a little throttle to make
sure that water discharges properly.
EJU40323Water separator
The water separator prevents water from en-
tering the fuel tank by collecting any water
that has entered the fuel tank breather hose if
the watercraft was capsized.
If water has collected in the water separator,
drain it by loosening the drain screw.
To drain water from the water separator:
(1) Place a drain pan or dry cloth under the
water separator.
(2) Gradually loosen the drain screw to drain
the water. Catch the draining water in the
drain pan or soak it up with the dry cloth
so that it does not spill into the engine
compartment. If any water spills into thewatercraft, be sure to wipe it up with a
dry cloth.
(3) Securely tighten the drain screw until it
stops.
EJU31665Engine overheat warning system
If the engine temperature rises significantly,
the engine overheat warning system will acti-
vate and the engine speed will be limited to
about 3400 r/min to help prevent damage.
If the engine overheat warning system is acti-
vated, immediately reduce the engine speed,
return to shore, and then make sure that wa-
ter is being discharged from the cooling wa-
ter pilot outlet while the engine is running. If
there is no discharge of water, stop the en-
gine, and then check the jet intake for clog-
ging. (See page 66 for information on the jet
intake.) NOTICE: If you cannot locate and
correct the cause of the overheating, con-
sult a Yamaha dealer. Continuing to oper-
ate at higher speeds could result in severe
engine damage.
[ECJ00042]
1Water separator
2Drain screw
2
1
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Operation
41
wake, but the watercraft is moving through
the water rather than skimming on top of it.)
At very slow speeds, it may be necessary to
support your upper-body weight with your el-
bows resting on the gunwales, trailing your
legs in the water.
Standing
After you are comfortable handling the water-
craft from a kneeling position, try standing as
the watercraft gains speed. The watercraft
will become easier to balance as the speed
increases, because jet thrust provides stabil-
ity as well as directional control. When you
are moving slowly, or preparing to stop, you
will probably need to return to the kneeling
position to maintain your balance.
EJU32822Launching the watercraft
When launching the watercraft, make sure
that there are no obstacles around you.If the watercraft is launched from a trailer,
someone should make sure that waves do
not push the watercraft into the trailer.
After the watercraft is in the water, turn it
around so that the bow faces the direction
you wish to go.
EJU32836Starting the engine on water
WARNING
EWJ01521
Do not apply throttle when others are at
the rear of the watercraft. Turn the engine
off or keep it at idle. Water and debris ex-
iting the jet thrust nozzle can cause severe
injury.
To start the engine:
(1) Move the watercraft to an area that is
free from weeds and debris, and has a
water depth of at least 60 cm (2 ft) from
the bottom of the watercraft. NOTICE:
Never run the engine in water that is
less than 60 cm (2 ft) deep from the
bottom of the watercraft, otherwise
pebbles or sand could be sucked into
the jet intake, causing impeller dam-
age and engine overheating.
[ECJ00473]
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Operation
49
see “Towing the watercraft” on page 68
or “Submerged watercraft” on page 69.)
NOTICE: Do not run the engine at full
throttle for at least 1 minute after the
engine has been restarted. Bilge wa-
ter in the engine compartment can
splash into the engine, which can re-
sult in severe damage.
[ECJ00554]
EJU33303
Beaching the watercraft
To beach the watercraft:
(1) Make sure that there are no boats, swim-
mers, or obstacles near the beach.
(2) Release the throttle lever to reduce
speed about 90 m (300 ft) before you
reach the intended beaching area.
(3) Slowly approach the beach and stop the
engine just before reaching land.
WARNING! You need throttle to steer.
Shutting the engine off can cause you
to hit an obstacle you are attempting
to avoid. A collision could result in se-
vere injury or death.
[EWJ00602] NOTICE:
Never run the engine in water that is
less than 60 cm (2 ft) deep from the
bottom of the watercraft, otherwise
pebbles or sand could be sucked into
the jet intake, causing impeller dam-
age and engine overheating.
[ECJ00473]
(4) Get off the watercraft and pull it up on the
beach.
EJU37194Operating in weeded areas
Always avoid using your watercraft in areas
where weed growth is thick. If operating in
weeded areas is unavoidable, alternately
squeeze the throttle lever and relax your grip
on the throttle lever to vary the engine speed.
Weeds tend to become clogged more when
operating at a steady speed and at trolling
speed. If weeds may have clogged the intakearea, clean the jet intake. (See page 66 for in-
formation on the jet intake.)
EJU41061After removing the watercraft from
the water
NOTICE
ECJ01361
Do not run the engine for more than 15
seconds on land without supplying water,
otherwise the engine could overheat.
After operating and removing the watercraft
from the water, promptly discharge the re-
maining water from the cooling water pas-
sages.
To discharge water from the cooling water
passages:
(1) Make sure that the area around the wa-
tercraft is clear, and then start the en-
gine.
(2) Discharge the remaining water out of the
cooling water passages by alternately
squeezing and releasing the throttle lever
quickly for 10 to 15 seconds.
(3) Stop the engine.
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