Cooling System; Changing Coolant - Westerbeke 5.0KW BCG-60Hz Operator's Manual

COOLING SYSTEM
FRESH WATER COOLING CIRCUIT
NOTE: Refer to the ENGINE COOLANT section for the
recommended antifreeze and water mixture to be used as the
fresh water coolant.
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 manifold,
to the heat exchanger where
it
is cooled, and returned to the
engine block via the suction side of the circulating
pump.When the engine is started cold, external coolant flow
is prevented by the closed thermostat (although some coolant
flow is bypassed around the thermostat to prevent the exhaust
manifold from overheating). As the engine warms up, the
thermostat gradually 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
ea~ily
accessible.
COOLANT RECOVERY
TANK
NOTE: Periodically check the condition of
the
manifold pres-
sure cap. Ensure
that
the upper and lower rubber seals are in
good condition and check that the vacuum valve opens and
closes tightly. Carry a spare cap.
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 fai/ures can be
traced back to cooling system co"osion.
Drain the engine coolant by removing the drain plug and
opening the manifold pressure cap. Flush the system with
fresh water, then reinstall the drain and start the refill process.
A
WARNING:
Beware of the hot engine coolant.
Wear protective gloves.
Refilling the Coolant
After replacing the engine drain plug, open the air bleed
petcock on the exhaust manifold and slowly pour clean,
premixed coolant into the manifold.
Monitor the coolant in the manifold and add as needed. Fill
the manifold neck. Once coolant begins flowing from the air
bleed petcock free of air bubbles, close the petcock and
install the manifold pressure cap.
Remove the cap on the coolant recovery tank and fill with
coolant mix to halfway between LOW and MAX and replace
the cap. Run the engine and observe the coolant expansion
flow into the recovery tank.
Mter checking for leaks, stop the engine and allow
it
to cool.
Coolant should draw back into the cooling system as the
engine cools down. Add coolant to the recovery tank if
needed and check the coolant in the manifold. Clean up any
spilled
coolant.
,-
COOLANT DRAIN
SEALS
LOCATED JUST BELOW
THE INTAKE MANIFOLD
CHECKING THE PRESSURE CAP
FROM COOLANT
RECOVERY TANK
MAKE CERTAIN THESE
PASSAGES ARE KEPT CLEAR
TO COOLANT
RECOVERY TANK
COOLANT RETRACTION
Engines & Generators
13
COOLANT EXPANSION