单项选择题
Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause（）
A.erosion and cratering of the nozzle orifices B.fuel leakage into the nozzle drain line C.fuel leakage before and after injection D.insufficient fuel delivery though that nozzle
单项选择题 Diesel engine cylinder head test cocks are used to （）
单项选择题 Which of the following statements is correct regarding a turbocharged four-stroke/cycle diesel generator?（）
单项选择题 Lubricating oil viscosity in an operating diesel engine can be reduced by（）
