单选题Cavitation erosion in the cooling water system of a diesel engine usually occurs at the pump impeller, and on the waterside of the （）Afuel nozzle holdersBexhaust value guidesCengine cylinder linersDlow temperature and a low viscosity
单选题
Cavitation erosion in the cooling water system of a diesel engine usually occurs at the pump impeller, and on the waterside of the （）
A
fuel nozzle holders
B
exhaust value guides
C
engine cylinder liners
D
low temperature and a low viscosity
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If the coolant temperature of a closed cooling water system for a diesel enginegradually increases, the trouble usually is( ).A.a broken shaft on the freshwater pumpB.an excessive accumulation of scale in the heat exchangerC.an incorrect thermostatic element operating rangeD.lube oil in the cooling water
If an auxiliary diesel engine coolant temperature is higher than normal, but the thermostat is determined not to be defective, you would suspect a/anA.cavitation erosion in the water jacketsB.excess corrosion inhibitor in the coolantC.dirty jacket water coolerD.defective turbocharger
In a diesel engine closed freshwater cooling system, the amount of coolant flowing through the heat exchanger is controlled by the __.A.suction pressure regulatorB.thermostatic bypass valveC.sea water temperatureD.water level in the expansion tank
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High diesel engine cooling water temperatures can be caused by ______.A.air in the cooling systemB.an overhauled water pumpC.correct amount of coolantD.no air in the cooling system
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单选题If the jacket water temperature in an auxiliary diesel engine cooling system is lower than normal, the probable cause is （）Aair binding of the engine cooling systemBa cracked water cooled exhaust manifoldCblockage in the heat exchangerDfaulty operation of the thermostat
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单选题In a closed cooling system for a turbocharged, four-stroke/cycle diesel engine, fluctuating water pressure can be caused by （）Aimproper venting of the cooling systemBcarrying the expansion tank water level too highCa totally clogged impeller in the cooling water pumpDan incorrectly set cooling system temperature control
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