单项选择题
A.through bolts B.dividing walls C.sloping surfaces D.relative angles
Smaller engines can be made more rigid than large ones ...
单项选择题Smaller engines can be made more rigid than large ones and may not have （）.
A.connecting rods B.crankshaft C.crankcase D.through bolts
Since the burning or combustion takes place within the ...
单项选择题Since the burning or combustion takes place within the engine itself, the engine is known as （）.
A.a fire -tube boiler B.an internal combustion engine C.an external combustion engine D.an internal combustion generator
Shims of different thicknesses are inserted between the...
单项选择题Shims of different thicknesses are inserted between the shells to enable adjustment of （）.
A.the bearing clearances B.the bearing thickness C.the bearing strength D.the bridge hardness
