Westerbeke W-46 - Page 58

COOLING SYSTEM
2. Raw Water Circuit
3.
Raw water is drawn into the raw water pump (positive displacement-
neoprene impeller type) by the suction action of the impeller in
the pump. This raw water is pumped to the raw water inlet of the
heat exchanger where it passes through. the tubes inside the
exchanger and removes heat from the fresh water coolant flowing
around the outside of the tubes. (Refer to the cooling system
illustration.}
The raw water is then discharged from the exchanger and then may
be directed to the transmission oil cooler. It then passes into
the exhaust injection elbow to be mixed with the exhaust gases,
cooling them as this mix falls into the exhaust muffler and is
pushed overboard by exhaust gas pressure.
Thermosta~ #024688 ~· ' ~~- '\_
1
The thermostat is· a wax type, U V\
designed to maintain engine
operating temperature between ~ ·-2
170"-190"F. (77"-88"C).
3.1 Disassembly
3
a. Remove thermostat cover (2)
by loosening and removing
bolts (1) and washer.
b. Remove thermostat (3),
gaskets (4) and spacer (5)
from engine block (6).
4. Fresh Water Pump #034370
The water pump is the centrifu-
gal type. Its bearings are
lubricated by water pump
bearing grease applied thru the
zerk fitting on the side of the
pump.
4.1 Disassembly
a. Loosen and remove water pump
shaft nut and lock washer;
remove water pump pulley
and woodruff key.
Remove pump cover (2) by
loosening and removing cover
attaching bolts (1).
~~~t==~
~;;;:;;;;~~-4
9
5
Engines & Generators
56
10
1 -Bolt
2-Cover
3-lmpeller
4-llnit seol
5-Spacer
2
3
6-Snap ring
7-Bearing
a-Shaft
9-Bearing
10-Housing