单选题Excessive vibration in an operating diesel generator may be caused by （）Aelectrical overloadBsurging at governed RPMCloose engine mounting boltsDcoolant leaking into the cylinder
单选题
Excessive vibration in an operating diesel generator may be caused by （）
A
electrical overload
B
surging at governed RPM
C
loose engine mounting bolts
D
coolant leaking into the cylinder
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