单项选择题
A.The oil temperature is less than the cooling water temperature
B.The oil pressure is less than the cooling water pressure
C.The oil pressure is greater than the cooling water pressure
D.The oil flow control valve is always installed in the oil input line
单项选择题 One method of constructing large marine diesel engines and reducing the total engine frame weight is through （）.
单项选择题 Prior to lighting off a cold automatically fired auxiliary boiler, you should （）.
单项选择题 Which of the following statements describes the function of an expansion tank in a diesel engine cooling system?（）