Hamilton Jet HJ241, Manual

Page: 30 / 202

2.8
2 SYSTEM OPERATION
2.10 O
PERATING WITH AN
E
NGINE AND
J
ET
U
NIT OUT OF
S
ERVICE
HJ-241 / HSRX
blockage. If this fails to work, repeat actions
a) to c) several times.
3. Remove the Inspection Cover on the Intake
Housing and manually clear the obstruction.
Refer to Section 2.9.4 Using the Inspection Cover.
NOTE:
1. Check that the static water level will be safely
below the lip of the Intake Inspection Cover.
2. If the static water level is too high, ballast
should be placed on the bow of the vessel to
raise the stern high enough to allow the
Intake Inspection Cover to be removed.
3. Alternatively, an optional extra Hatch
Extension can be fitted to the Inspection
Cover to allow inspection of the Intake
Housing at higher water levels. Refer to
Drawing
HJ-241-10-004 Hatch Extension.
2.9.4 Using the Inspection Cover
Inspection Hatch Extension (Optional Extra)
NOTE: Refer to Drawings HJ-241-10-004 Hatch
Extension .
The Inspection Hatch Extension is an optional extra
for use with Jet Units where the water level is above
the normal level of the Inspection Cover.
1. It is attached to the top of the Intake Casing in
place of the Inspection Cover. The Inspection
Cover is then fitted to the upper end of the
Inspection Hatch Extension.
2. It provides an increase of approximately 150 mm
in allowable water level height.
2.10 OPERATING WITH AN
ENGINE AND JET UNIT OUT
OF SERVICE
If the vessel is operated with an engine and Jet Unit
out of service, it is possible for the Jet Unit Mainshaft
to rotate due to water flowing through the Jet Unit.
This is undesirable as it can lead to damage of the
gearbox.
USE OF SHAFT BRAKE (IF FITTED) TO STOP
MAINSHAFT ROTATION:—
The Shaft Brake should
be fitted to the output shaft of the Gearbox. Apply
the Shaft Brake to stop the Jet Unit Mainshaft
rotation in Jet Units not in service.
USE OF ENGINE TO STOP MAINSHAFT
ROTATION:—
If a Shaft Brake is not fitted, the Jet
Unit Mainshaft can be prevented from rotating by
engaging the Gearbox of the Engine which is out of
service.
NOTE: When using this method, it is possible for the
Jet Unit to rotate the Engine. If this occurs,
disengage the Gearbox and let the Jet Unit
Mainshaft rotate.
W
ARNING
Extreme care is required whenever
the Inspection Cover is removed as
water may enter the vessel
through this opening.
Never leave the Inspection Cover
removed without constant
monitoring of the water levels.
C
AUTION
Before Removing the Inspection
Cover:-
a) Stop all engines.
b) Check that the static water
level will be below the Intake
Inspection Cover Lip.
c) If the static water level is too
high, ballast should be
placed on the bow to raise
the stern high enough to al-
low the Intake Inspection
Cover to be removed.
d) Alternatively, an optional
Hatch Extension/Overflow
Preventor can be fitted to the
Inspection Hatch opening to
allow inspection of the Intake
at higher water levels.