单项选择题
A.the clearance of the main bearing B.the play of the miler bearing C.the gap of the main bearing D.the tolerance of the main bearing
Marine four-stroke diesel engines are mainly （）.A.of cr...
单项选择题Marine four-stroke diesel engines are mainly （）.
A.of crosshead type B.of trunk piston type C.of low speed type D.all the above
Main bearings are required to support the crankshaft at...
单项选择题Main bearings are required to support the crankshaft at each （）.
A.end B.web C.pin D.journal
Lubricating oil for an engine is stored at the bottom o...
单项选择题Lubricating oil for an engine is stored at the bottom of the （）, known as the sump or in a drain tank located beneath the engine.
A.sea cheat B.air receiver C.crankcase D.water box
