Hydraulic pumps refer to mechanical devices that move or displace liquid to convert mechanical energy into hydraulic energy. Hydraulic pumps can develop operational problems that can lead to a discernible whining noise, which may indicate a serious system problem. Fortunately, this noise can be quieted via a few simple troubleshooting techniques.
Relief Valve Check
Hydraulic pumps typically include a relief valve, or valve that opens and closes to control the pressure in a hydraulic system. Oil buildup or other sediment in the relief valve can hamper its ability to close properly, thereby enabling higher pressure to pass through the system, resulting in a whistling noise. Cleaning the relief valve with a damp cloth typically corrects the problem.
Foil, flashing or other objects lodged in the hydraulic pump's inlet, or opening that allows hydraulic fluid into the pump, can restrict the pump's intake and result in a whining noise. Cleaning out or removing any obstructions at the pump's inlet should eliminate the whining.
Leaks in one or multiple hydraulic lines can allow air or moisture to mix with hydraulic oil. This added air can result in a high-pitched whine while the hydraulic pump is in operation. Replacing the damaged lines should resolve the whining issue and restore optimum function to the pump.