单项选择题
Heat damage to fuel injection nozzles on small high-speed diesel engines, can be prevented by（）
A.employing fuel oil as a cooling medium
B.preventing hard carbon deposit on nozzle tips
C.avoiding fuel oil temperature exceeding builder’s specification
D.ensuring good metallic contact between nozzles and cylinder heads
相关考题
-
单项选择题
One of the advantages in the use of a dry liner over a wet liner is（）
A.it is fitted with neoprene O-ring seals
B.the honing process makes it easier to maintain the desired oil film
C.there is likelihood of water leaking into the combustion space
D.it fits more loosely due to a decrease in heat transfer through the composite wall -
单项选择题
One characteristic of a pulse type turbo-charging system is（）
A.high average exhaust manifold
B.greatly fluctuating inlet manifold pressure
C.constant exhaust manifold pressure
D.multiple exhaust pipes to the turbocharger -
单项选择题
One advantage of dry cylinder liners used in a diesel engine is the（）
A.lower thermal expansion rates than wet liners
B.greater heat transfer rate than wet liners
C.greater wear resistance than wet liners
D.procedure to replace dry liners is simpler than for wet liners
