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單項(xiàng)選擇題

Operating a diesel engine for prolonged periods, with a closed freshwater cooling system, at temperatures lower than the normal design temperature can cause （）.

A.the formation of sulfuric acid
B.a decrease in lube oil viscosity
C.a decrease in cooling water pH
D.a thermostat failure

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單項(xiàng)選擇題

Improper maintenance of the fuel oil burners in an automatically fired auxiliary boiler, could result in （）

A.increased fuel consumption
B.increased feed water consumption
C.fuel pump failure
D.combustion control system failure

單項(xiàng)選擇題

Which of the following conditions may need to be reduced when operating a large, low speed, main propulsion, diesel engine at low loads?（）

A.Injection pressures
B.Control air supply pressure
C.Cooling water flow through after-coolers
D.Lube oil temperature

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