单项选择题
Valve cages are used on some large diesel engines to （）
A.reduce wear on the valve stem B.permit the use of alloy valve seat materials C.reduce heat transfer from the valve seat D.facilitate valve removal for servicing
单项选择题 If the jacket water temperature rises rapidly above normal in a diesel engine, you should FIRST （）
单项选择题 Which of the following conditions can cause excessive lube oil consumption in a diesel engine?（）
单项选择题 In the common rail system, excessive pressure in the header may be caused by （）
