（） fuel oils （） lubricating oils require treatment before passing to the engine.

[单选题]The ability of lubricating oils to resist viscosity changes during temperature changes is indicated by the ____.A．American PetroleumB．Institute number viscosity index numberC．Seconds Saybolt Furol numberD．Seconds Saybolt Universal number

[单选题]The development of oils （） the increasing demands made by the steady rise in powers produced by modem diesels.A . has kept pace withB . has kept pace toC . has made pace withD . has made pace to

[单选题]E．mulsion oils and sodium nitrite are both approved additives, but the latter cannot be used if any pipes are or if ally soldered joints exit.A．chromedB．weldedC．galvanizedD．bolted

[单选题]Emulsion oils and sodium nitrite are both approved additives, but （） cannot be used if any pipes are galvanized or if soldered joints exist.A . the latterB . latterC . formerD . the former

[单选题]The lubricating system for the cylinder walls is different from the bearings in that the oil for former one is supplied in （） while that for latter one is （）.A . sufficient quantity； measuredB . measured quantity；sufficientC . excessive quantity；suff

[单选题]The function of a lubricating oil is （） to lubricate the running surface （） to carry away a great deal of heat.A . not；butB . neither；norC . either；orD . not only；but also

[单选题]With respect to the flow of lubricating oil through a diesel engine, the lube oil coolers are located after filters in order to （）.A . allow filtration of less viscous oilB . decrease the pressure drop across the filterC . improve overall filtrationD

[单选题]During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.A . ensure penetration and distribution of the fuel in the combustion chamberB . ensure the needle valve is flushed clean during each injectionC . prevent combust

[单选题]Fuel injection systems meter fuel, atomize fuel, and （）.A . create turbulence in the combustion chamberB . aid in completing cylinder scavengingC . inject fuel at the proper timeD . minimize fuel penetration into the cylinder

[单选题]Fuel injectors used in heavy fuel oil systems are usually provided with cooling to reduce（）.A . cold corrosion of the nozzlesB . fuel viscosity for better atomizationC . carbon accumulation on the nozzlesD . fuel detonation in the cylinder