Specifications
COOLING
CIRCUIT
DESCRIPTION
Westerbeke diesel engines are designed and equipped
for
fresh water cooling. Heat produced in the engine
by
combustion and friction
is
transferred
to
fresh water coolant
which circulates throughout the engine. This circulating fresh
water coolant cools the engine block and its internal moving
parts and the engine oil.
Fresh water coolant is pumped through the engine by a
circulating pump, absorbing heat from the engine.
The
coolant then passes through the thermostat into
the
radiator
where it is cooled, and returned to the engine block
via
the
suction side
of
the circulating pump.
FRESH
WATER
COOLING
CIRCUIT
NOTE:
Refer to
ENGINE
COOlANT
section
for
the
recommended antifreeze and water mixture to be used as the
fresh water coolant.
When the engine is started cold, external coolant
flow
is
pre-
vented by the closed thennostat (although some coolant
flow
is
bypassed around the thermostat to prevent the engine from
overheating).
As
the engine warms
up,
the thermostat gradu-
ally opens, allowing full flow
of
the engine's coolant to
flow
unrestricted
to
the external portion
of
the cooling system.
Coolant
Recovery
Tank
A coolant recovery
tank
allows for engine coolant expansion
and contraction during engine operation, without any
significant loss
of
coolant and without introducing air into
the cooling system. This
tank should be located at or above
the engine manifold level and should be easily accessible.
CHANGING
COOLANT
The engine's coolant must
be
changed according
to
the
MAINTENANCE
SCHEDULE.
If
the coolant
is
allowed
to
become contaminated, it
can
lead to overheating problems.
A
CAUTION:
Proper
cooling
system
maintenance
is
critical;
a
substantial
number
of
engine
failures
can
be
traced
back
to
cooling
system
corrosion.
Drain the engine coolant
by
removing the drain plug under
the
manifold and opening the manifold pressure cap. Flush
the
system with fresh water, then start the refill process.
A
WARNING:
Beware
of
the
hot
engine
coolant.
Wear
protective
gloves.
Refilling
the
Antifreeze
Coolant
System
Re-install the engine block drain plug. Close the drain
pluglpetcock on the radiator. Pre-mix your antifreeze and add
it
to
the radiator until the system is visibly near full.
Start the generator and continue to add the antifreeze mix
as
air
is
expelled. Observe
the
engine operating temperature.
As
the temperature nears 180°F. The thermostat should be
opening
and
flow
through the radiator observed.
When
all the air
is
expelled, top
off
the radiator and install
the
pressure cap, now add more antifreeze mixture to the
remote recovery
tank
until half full.
Inspect the system for any leaks.
Stop the engine and allow
the system
to
cool down. Coolant in the plastic coolant •
recovery tank should be drawn into the engines cooling
system.
Add enough coolant to the recovery
tank
to place the
level between the add and max marks.
Engines & Generators
14