Engine Systems EBWOIT DIESEL ee To effectively dissipate the heat generated by the engine, one of three different types of cooling systems is used on a V-71 engine; radiator and fan, heat exchanger and raw water pump, or keel cooling. Each system is provided with a centrifugal type water pump that circulates the engine coolant. Each system incorporates thermostats to maintain a normal engine operating temperature of 160-185 OF (71-85’ C). A typical cooling system is illustrated in Fig. 19. oil cooler housing and into the cylinder block.
From the cylinder block the coolant passes up through the cylinder heads and, when the engine is at normal operating temperature, through the thermostat hous- ings and into the upper portion of the radiator. Then the coolant passes down a series of tubes where the coolant temperature is lowered by the air stream created by the revolving fan. Upon starting a cold engine or when the coolant is below operating temperature, the coolant is restricted at the thermostat housing and a by-pass provides water circulation within the engine during the warm- up period.
Radiator and Fan Cooling Coolant is drawn from the lower portion of the radiator by the water pump and is forced through the TO RADIATOR Fig. 19 - Cooling System