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單項選擇題

Before pumping up the crankcase oil,（） should be worked by hand to minimize corrosive action on the liners.

A.the indicators
B.the starting valves
C.the cylinder lubricators
D.the turning gear

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單項選擇題

Before being used the fuel service tank should be drained of （）.

A.soda solution
B.mechanical impurities
C.ballast
D.water and residuals

單項選擇題

Before a marine diesel engine is started the cylinders and pistons must be （）.

A.cooled to appropriate temperature
B.warmed up gradually to appropriate temperature
C.opened up and renewed
D.ground and polished

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