Raw Water Pump - Westerbeke 3.0KW BPMG-60HZ Service Manual

RAW WATER PUMP
IMPELLER
DESCRIPTION
Coolant (fresh water) cooled generators have dual water
pumps while the raw water cooled models use a single water
pump. The pumps are essentially the sarne. The upper pump
mounts to the top of the lower pump and has a tang on the
shaft that fits into the shaft of the lower pump. Both pumps
are driven simultaneously by the engines drive belt.
The following instructions apply to either pump:
PUMP OVERHAUL
Disassembly
The pump when removed from the engine will have the hose
attachment nipple threaded into the inlet and outlet ports of
the pump along with a drive pulley attached
to
the shaft of
the pump. remove these attachments noting their positions
before starting the pump disassembly.
1. Remove the four cover plate screws, cover plate, and
sealing O-ring.
Dual Pumps
Remove the cover screws
and
the cover
will
separate the
upper pump (raw water) from the fresh water (coolant)
pump as shown in the illustration.
Remove the wear plate to expose the impeller. Notice the
direction the impeller blodes are working in so as to install
the replacement impeller with blodes working in the same
direction.
2. Remove the impeller using a pair of pliers, grasping the
hub and pulling it out of the pump with a twisting motion.
3. Remove the screw and sealing washer that hold the earn in
place. remove the cam and inner wear plate behind it.
4. Remove the dust plate and circlip.
S. Support the pump body on an arbor press and with a drift,
press the shaft and bearing assembly out of the pulley end
of the pump.
6. Remove the O-ring from the shaft.
7.
Support the outer bearing and push the shaft out of the
bearing.
S. Remove the spacer and circlip .
Inspection
Inspect all parts and replace those showing wear and
corrosion.
SCREWS
INSPECTION: CHECK AT THE BASE OF
EACH BLADE BY BENDING
VIGDROUSL~
REPLACE THE IMPELLER IF THERE
ARE ANY CRACKS.
INSPECT THE D·RING
AND IMPELLER. REPLACE
IF ANY SIGNS OF WEAR
OR TEARING
CIRCLIP
DUST
IMPELLER PIN
FITS INTO SHAFT
SHAFT
D·RING
INNER
BEARING
SPACER
OUTER
BEARING
CIRCLIP
PLATE
""'''''''v
LIGHTLY GREASE THE PUMP
CHAMBER WITH GLYCERIN
~ETSCREW
PULLEY
Engines
&
Ge,nerators
36