单项选择题
A.piston cooling B.sleeve cooling C.central cooling D.jacket cooling
Cross scavenging requires the fitting of （） to prevent ...
单项选择题Cross scavenging requires the fitting of （） to prevent air or exhaust gas escape when the piston is at the top of the stroke.
A.a exhaust valve B.a piston skirt C.a piston crown D.an air suction valve
Crankshafts of medium speed engines are （） from a singl...
单项选择题Crankshafts of medium speed engines are （） from a single piece of steel.
A.unusually solid welded B.never be solid forged C.almost invariably solid forged D.almost invariably be welded
Cracks in the cylinders and cylinder covers may （） uneq...
单项选择题Cracks in the cylinders and cylinder covers may （） unequal heating.
A.result from B.result in C.give out D.given from
