Thermostat
The engine is equipped with a thermostat whose sen-
sor body contains wax.
When
the
engine is cold the thermostat keeps the route
to the heat exchanger closed. Coolant then passes
through a by-pass line, directly back to the suction side
of the pump. As the engine warms up, the volume of
the wax increases and the thermostat progressively
opens the passage to the heat exchanger, at the same
time as the by-pass line is closed.
Refer to Group 26: Cooling System page 22 for open-
ing temperatures.
The thermostat is located in a housing which is inte-
grated in the heat exchanger and exhaust manifold.
Coolant Pump
The coolant pump is mounted on the engine block and
is driven by the crankshaft by means of a drive belt.
Seawater Pump
The raw water pump is a rubber impeller type pump
mounted on the front of the engine. The pump is driven
by the engine timing and pumps cooling water to the
engine heat exchanger.
NOTICE! The impeller will be damaged if the pump is
run dry.
20-0 Engine Information, General
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