单项选择题
A.Excessive compression in the cylinder
B.A broken intake valve
C.A dirty inlet filter element
D.An improperly adjusted discharge valve
单项选择题 In which of the listed hydraulic systems will the installation of an oil cooler be necessary?（）
单项选择题 Which of the following problems would be the probable cause for the faulty operation of a reciprocating air compressor suction valve?（）
单项选择题 If a refrigeration crankcase compressor were short cycling on the low pressure cutout switch, the cause might be that the （）.