单项选择题
If a single cylinder relief valve on a diesel engine lists frequently while the engine is running, the cause may be an （）
A.excessively late injection timing for each cylinder B.incorrectly adjusted intake valve timing C.incorrectly adjusted fuel injector D.incorrectly adjusted intake valve clearance
单项选择题 Which of the diesel engine cylinder liners listed has internal cooling water passages?（）
单项选择题 Diesel engine lube oil can become contaminated as a result（）
单项选择题 If the firing pressures in a diesel engine are high, although the exhaust temperatures are normal, the cause may be（）
