单选题Heat damage to fuel injection nozzles on small high-speed diesel engines, can be prevented by（）Aemploying fuel oil as a cooling mediumBpreventing hard carbon deposit on nozzle tipsCavoiding fuel oil temperature exceeding builder’s specificationDensuring good metallic contact between nozzles and cylinder heads
单选题
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
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