单项选择题
In a diesel engine, an extremely leaking exhaust valve can cause （）.
A.misfiring B.pre-ignition C.interrupted scavenging D.reduced scavenging
单项选择题 Diesel engine exhaust temperatures may be used to indicate （）.
单项选择题 In a bypass type lubrication system for a diesel engine, the dirty oil line to the centrifuge should be taken from the （）.
单项选择题 Theoretical perfect combustion in a diesel engine yields by-products of （）.
