单项选择题 The injection may be delayed, （）the pumps are in good order, if the fuel lines to the injection valves have not been cleared of air.

单项选择题 If cylinder liner wear is up to maximum limits the possibility of scavenge fires will not be materially reduced until the liners are （）.

单项选择题 Fuel injection equipment must be kept in good condition, timed correctly, and the （）in each cylinder must also be carefully balanced so that individual cylinders are not overloaded.