单项选择题
One of the purposes for water cooling the exhaust manifold in marine diesel engine is to （）
A.reduce lube oil temperature B.raise exhaust temperature reduce C.excessive heating of engine room D.reduce load on cooling water pump
单项选择题 A condition contributing to diesel engine piston rings sticking in the ring grooves, is insufficient ring clearance at the ring（）
单项选择题 An auxiliary diesel engine may fail to start due to（）
单项选择题 Diesel engine exhaust noise can be reduced in an exhaust muffler by （）
