单选题Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by（）Apermanent loss of pump suctionBworn shaft sealsChigh level in the oil sumpDlow motor RPM
单选题
Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by（）
A
permanent loss of pump suction
B
worn shaft seals
C
high level in the oil sump
D
low motor RPM
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