Yanmar 3JH4E, Service Manual

Page: 285 / 350

9. Coolant system
265
9.2.2 Seawater pump disassembly
Refer to 2.2.4.(5).
(1) Remove the rubber hose from the
seawater pump outlet and then the
seawater pump assembly from the gear
case (flange).
(2) Remove the side cover and take out the
O-ring, impeller and wear plate.
(3) Remove the retainer, washer and
mechanical seal.
(4) Insert plier from the drive gear side and
remove the retainer that holds the
bearing.
(5) Lightly tap the pump shaft from the
impeller side and remove the pump
shaft and bearings as a set.
(6) Remove the lip seal and mechanical
seal if necessary.
9.2.3 Seawater pump Inspection
(Refer to 2.2.4(5).)
(1) Inspect the rubber impeller, checking for
splitting around the outside, damage or
cracks, and replace if necessary.
(2) Inspect the mechanical seal and replace
if the spring is damaged, or the seal is
corroded. Also replace the mechanical
seal if there is considerable coolant
leakage during operation.
(3) Make sure the ball bearings rotate
smoothly. Replace if there is excessive
play.
Coolant leakage
less than 3 cm
3
/h
Side cover
O-ring
Impeller
Wear plate
Retainer
Washer
Mechanical seal
V-ring
Pump body
Lip seal
Lip seal
Bearing
Retainer
Pump shaft
010699-00E