单选题Overheating of a hydraulic system may be a result of （）.Achanging pump discharge pressure in response to normal load variationsBa high oil levelCincorrect fluid viscosityDcontinued slow re-circulation of the oil
单选题
Overheating of a hydraulic system may be a result of （）.
A
changing pump discharge pressure in response to normal load variations
B
a high oil level
C
incorrect fluid viscosity
D
continued slow re-circulation of the oil
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