Table of Contents
Advertisement
COOLING SYSTEM
RAW WATER INTAKE STRAINER
NOTE:
Always install the strainer at or below the waterline so
the strainer will always be self-priming.
A clean raw water intake strainer is a vital component of the
engine's cooling system. Include a visual inspection of this
strainer when making your periodic engine check. The water
in the glass should be clear.
Perform the following maintenance after every 100 hours of
operation:
1.
Close the raw water seacock.
2. Remove and clean the strainer filter.
3. Clean the glass.
4. Replace the washer if necessary.
5. Reassemble and install the strainer.
6. Open the seacock.
7. Run the engine and check for leaks.
NOTE:
Also follow the above procedure after having run hard
aground.
RAW WATER PUMP
The raw water pump is a self-priming, rotary pump with a
non-ferrous housing and a Neoprene impeller. The impeller
has flexible blades which wipe against a curved cam plate
within the impeller housing, producing the pumping action.
Never allow the pump to run dry. There should always be
a spare impeller and impeller cover gasket aboard (an
impeller kit). Raw water pump impeller failures occur when
raw water is not present during engine operation. Such
failures are not warrantable, and operators are cautioned to
make sure raw water flow is present at start-up. The raw
water pump should be inspected periodically for broken or
tom impeller blades. See MAINTENANCE SCHEDULE.
NOTE:
Should a failure occur with the pumps internal parts
(seals and bearings), it may be more cost efficient to
purchase a new pump and rebuild the original pump as
a spare.
NOTE:
Never allow the. pump to run dry. Even a short period
of dry running may destroy the impeller.
IMPELLER
INSPECTION: CHECK AT THE BASE OF
EACH BLADE BY BENDING VIGOROUSLY.
REPLACE THE IMPELLER IF THERE
ARE ANY CRACKS.
WHEN INSTALLING: TAKE CARE TO ALIGN
THE IMPELLER KEYWAY WITH THE SHAFT
KEY. FOLD THE IMPELLER BLADES IN
EITHER DIRECTION (THEY WILL TURN IN
THE CORRECT POSITION WHEN THE
IMPELLER STARTS TO ROTATE).
RAW WATER
PUMP
PN 042026
WHEN ASSEMBliNG: APPLY A THIN COAT OF
GLYCERIN TO THE INSIDE OF THE COVER, THE
If the engine temperature warning light LED illuminates, the
cause may be that silt, leaves or grass may have been caught
up in the strainer. slowing the flow of raw water
thro11~h
thP
cooling system.
TYPICAL RAW WATER INTAKE STRAINER
(OWNER /NSTALLElJ)
INCOMING
RAW WATER
SEACOCK
INSPECT AND
CLEAN EVERY
toO HOURS
+
NOTE:
The external thru-hull opening should be of the flush
type with a clear opening. No perforated or slot type external
opening. Let all the filtering be accomplished on the inside of
the hull where there is easy access to
t~e
strainer.
Changing the Raw Water Pump Impeller
Close the raw water intake valve. Remove the pump cover
and, using an impeller puller, screw drivers, or pliers,
carefully pry the impeller out of the pump. Install the new
impeller and gasket. Move the blades to conform to the
curved cam plate and push the impeller into the pumps hous-
ing. When assembling, apply a thin coating of lubricant to
the impeller and gasket. Open the raw water intake valve.
NOTE:
Should a failure occur with the pumps internal parts
(seals arid bearings), it may be more cost efficient to
purchase a new pump and rebuild the original pump as
a spare.
NOTE:
If any of the vanes have broken off the impeller they
must be found to prevent blockage in the cooling circuit.
They often can be found in the heat exchanger.
COVER 0-RING, AND THE IMPELLER
~
WESTERBEKE
Engines
&
Generators
·16
Advertisement
Table of Contents
