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單項(xiàng)選擇題

During （）, the starting air valves should be closed to prevent the engine from turning.

A.overhaul
B.running
C.blowing down
D.All of the above are correct

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單項(xiàng)選擇題

Due to （） action of pistons some relative motion between parts in contact in the coolant supply and return system must occur.

A.reciprocating
B.rotating
C.running
D.removing

單項(xiàng)選擇題

Doors are generally formed in the （） of the both in-line and Vee engines to give maintenance access to the crankshaft main and connecting rod large end bearing.

A.bedplates
B.columns
C.cylinder blocks
D.safety caps