单项选择题
A.worn valve seats B.worn main bearing C.excessive valve clearance D.weak rocker arm springs
In the cylinder of a diesel engine fuel is ignited by t...
单项选择题In the cylinder of a diesel engine fuel is ignited by the（）
A.spark from a plug in the pre-combustion chamber B.electrical discharge from the distributor C.heat of compression within the cylinder D.heat from the fuel injection nozzle
Diesel engine air start valve timing is controlled by（）...
单项选择题Diesel engine air start valve timing is controlled by（）
A.engine operating speed B.an air manifold C.a hydraulic distributor D.individual cams and valve gear
The timing of diesel engine air starting valves is cont...
单项选择题The timing of diesel engine air starting valves is controlled by（）
A.the air start valve timing gears and rods B.a cylinder check valve C.individual cams and valve gear D.an air manifold poppet valve
