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3) MOISTURE IN OIL:
a) Fill pipes left open.
b) Moisture in container used to replace oil in tank.
c) Extreme temperature differential.
4) OVERHEATING OF SYSTEM:
a) Continuous operation at relief setting.
b) Excessive slippage or internal leakage.
c) Fluid viscosity too high or low.
d) Hose I.D. too small causing high velocity.
e) Improper air circulation around reservoir.
f) System relief valve set too high.
g) Power unit operating in direct sunlight or ambient temperature is too high.
5) PUMP MAKES EXCESSIVE NOISE:
a) Check for vacuum leaks in suction line.
b) Vacuum leak at pump shaft seal.
c) Check alignment with drive mechanism. Misalignment will cause wear and
subsequent high noise level operation.
d) Relief valve set too high.
e) Aeration of fluids in reservoir (return line above fluid level.)
f) Worn cam ring, damaged gear, faulty bearing.
g) Reversed rotation.
h) Plugged lines.
i) Oil viscosity too high or temperature too low.
j) Loose or worn pump parts.
k) Pump housing bolts loose or not properly torqued.
