单项选择题
A.changes the position of the fuel inlet ports
B.changes the length of the pump stroke
C.varies the quantity of fuel delivered
D.varies the compression of the delivery valve spring
单项选择题 During extremely cold weather, while starting an engine, it turns too slowly and fails to startThis problem is most likely the result of （）
单项选择题 Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started?（）
单项选择题 Adjustments to the compensating needle valve in a hydraulic governor should be made with the engine at （）