单项选择题
A.cam followers B.push rods C.combustion gases D.valve springs
The outlet from an expansion tank of a closed freshwate...
单项选择题The outlet from an expansion tank of a closed freshwater cooling system should be piped to the ().
A.cylinder head water outlet header B.cylinder jacket inlet main C.heat exchanger inlet connection D.jacket water pump suction line
Passages are drilled in the crankshafts of diesel engin...
单项选择题Passages are drilled in the crankshafts of diesel engines to provide lubricating oil to the ().
A.main bearings B.connecting rod bearings C.piston pin bushings D.All of the above
After a normal, or safety shutdown, automatic combustio...
单项选择题After a normal, or safety shutdown, automatic combustion control systems for an auxiliary boiler are designed to prevent the immediate refiring of a burner in order for the ().
A.furnace to be re-purged B.electric charge to buildup in the igniter C.fuel pump to restart D.dram level to stabilize