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單項選擇題

A large, low-speed, main propulsion diesel engine uses sea water to directly cool the （）.

A.cylinder heads
B.exhaust valves
C.scavenging air
D.injectors

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單項選擇題

Lube oil pumps taking suction from the sump of most small marine engines are usually （）.

A.of the diaphragm type
B.of the centrifugal type
C.of the positive displacement type
D.independently driven by electric motors

單項選擇題

Fuel oil begins injection into the cylinder of a four-stroke/cycle diesel engine during the （）.

A.intake stroke
B.exhaust stroke
C.power stroke
D.compression stroke

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