FLOW OF COOLANT

COOLING SYSTEM

SYSTEMS OPERATION

(Marine Engines)

FLOW OF COOLANT

6. Inside bypass. 8. Housing for water

temperature regulators. 15. Passage to lower

part of expansion tank. 16. Return to housing

for water temperature regulators. 17. Water

temperature regulators (two). A. Flow with

warm coolant. B. Flow with cold coolant.

A small part of the coolant from the lower

compartment of expansion tank (2) goes through a small

vent tube into the upper compartment of expansion tank

(2). This coolant goes through shunt line (4) to the inlet of

water pump (9). This shunt type system keeps a positive

pressure on the inlet of water pump (9) at all times.

CAUTION: Never run an engine unless the water

temperature regulators are installed. With no water

temperature regulators in the system the coolant will

continually bypass the expansion tank and heat

exchanger and the engine will get too hot.

LOCATION OF WATER TEMPERATURE REGULATORS

Sea water pump (1) is installed on the left side of the

front cover for the engine and is driven by a V belt from

the crankshaft pulley.

Sea water is sent by sea water pump (1) to heat

exchanger (5). From the heat exchanger the sea water

goes to exhaust risers (3). After going through exhaust

risers (3) the sea water mixes with the exhaust gases

and goes through outlet for sea water (7).