Installation manual
COOLING
SYSTEM
FRESH
WATER
COOLING
CIRCUIT
NOTE:
Refer to the ENGINE COOLANT section
for
the
rec-
ommended antifreeze and water mixture to be used as the
fresh water coolant.
Fresh water coolant
is
pumped through the engine by a circu-
lating pump, absorbing heat from the engine. The coolant
then passes through the the1mostat 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
pre-
vented
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 s:rstem.
KEEP
THE
TO
COOLANT
RECOVERY
TANK
COOLANT
PASSAGE
CLEAR
FROM
COOLANT
RECOVERY
TANK
COOLANT
EXP4NS/ON
PRESSURE
/CAP
NOTE:
Periodically check the condition
of
the manifold
pressure
cap.
Ensure the upper
and
lower rubber seals are in
good
condition. Check to ensure
the vacuum valve opens
and
closes tightly.
Cany
a spare
cap. Check also to ensure the
coolant passage is clear so
coolant within
the.
system is
able to expand and contract
SEAL
to
and
from the coolant recove1ytank.
Coolant
Recovery
Tank
A coolant recovery tank allows for engine coolant expansion
and contraction during engine operation, without any signifi-
cant loss of coolant and without introducing air into the cool-
ing system. This tank should be located at or above the
engine manifold level and should be easily accessible.
NOTE:
This
tw1.k,
with its
sh011
run
of
plastic hose, is best
located at
or
above the level
of
the engines manifold.
CHANGING
COOLANT
The engine's coolant must be changed according
to
the
MAINTENANCE SCHEDULE.
If
the coolant
is
allowed
to
become contaminated, it can
kad
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 loosening the drain plug on the
engine block and opening the manifold pressure cap. Flush
the system with fresh water, then start the refill process.
NOTE:
The drain on the heat exchanger should also be used
to
help_
drain engine coolant.
OIL
GALLERY
Refilling
the
Coolant
After closing the engine block drain, pour clean, premixed
coolant into the manifold and when the coolant
is
visible
in
the manifold, start the engine and run it at slow idle. Open
the air bleed petcocks on the manifold and the thermostat
housing.
Monitor the coolant in the manifold and add
as
needed. Fill
the manifold to the filler neck and when the coolant flowing
from the petcock
is
free
of
air bubbles, close the petcock and
install the 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. When the petcock on the thermo-
stat housing
is
free
of
air bubbles, close that petcock.
After 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. Clean
up
any spilled coolant.
A
WARNING:
Beware
of
the
hot
engine
coolant.
Wear
protective
gloves.
/-w"/WESTERBEKE
I Enaines & Generators
15