单项选择题
Which of the listed design features is found in an exhaust valve and NOT in an intake valve?（）
A.Hard alloy steel construction B.Beveled edges on the valve head C.Low alloy steel construction D.Poppet type design
单项选择题 A diesel engine cylinder head can crack as a result of （）
单项选择题 In large, low-speed, main propulsion diesel engine, position ring groove wear usually occurs at the（）
单项选择题 Diesel engine blow-by is the leakage of combustion gases past the （）
