Yanmar 3JH4E, Руководство по обслуживанию

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2. Inspection and adjustment
76
(5) Check the impeller of the seawater
pump.
1) Remove the seawater pump cover and take
out the O-ring, impeller and wear plate.
2) Inspect the rubber impeller, checking for
splitting around the outside, damage or
cracks, and replace if necessary.
Depending on the use, the inside parts of a
seawater pump may deteriorate and the
discharge performance may drop. At the
specified interval or when the discharge volume
of seawater is reduced, inspect the seawater
pump in accordance with the following
procedures.
1) Loosen the seawater pump cover set bolts
and remove the side cover.
2) Illuminate the inside of the seawater pump
with a flashlight and inspect.
3) If no damage is found, reassemble the cover.
4) If any of the following problems are found,
take out the O-ring, impeller and wear plate. If
necessary, replace with new one and
reassemble the side cover.
• Impeller blades are cracked or nicked. Edges
or surfaces of the blades are marred or
scratched.
Note:
The impeller must be replaced periodically
(every 1000 hrs or four years whichever
comes first).
• Wear plate is damaged.
5) If a large amount of water leaks continuously
from the water drain pipe beneath the
seawater pump during engine operation,
check the lip seal inside the seawater pump.
The seawater pump turns in the
counterclockwise direction, but the impeller must
be installed by turning in the clockwise direction.
If the impeller has been removed for any reason
and must be reassembled, be very careful not to
make a mistake and turn it in the wrong direction.
Additionally, if the engine is being turned
manually, be careful to turn it in the correct
direction. Incorrect turning will twist the impeller
blades and damage it.
Cover
Pump body
O-ring
Impeller
Wear plate
010620-00E
Direction of
rotation
008437-01E