单项选择题
A.smoky B.a little bit dense C.visible D.almost invisible
The engine will fail to start unless （）.A.the pressure ...
单项选择题The engine will fail to start unless （）.
A.the pressure of the starting air is high enough B.there is enough air in the air reservoirs C.the air is supplied into the cylinders in the appropriate sequence D.all of the above
“The engine not obtaining the sufficient speed for firi...
单项选择题“The engine not obtaining the sufficient speed for firing” means that （）.
A.the start fails B.the fuel pumps will be put into operation C.the fuel valves are damaged D.the combustion process will take over
The engine may lose power or slow down during running, ...
单项选择题The engine may lose power or slow down during running, when this occurs, the first cause possible may be hot bearings and （） of the pistons in the cylinders.
A.crack B.knocking C.leaking D.seizure
