What causes a hydraulic pump shaft to wear out?

Prematurely worn shaft seals may be caused by excessive oil temperature. At temperatures of 200°F and higher, rubber seals have a very short life. Abrasives in the oil may wear seals out quickly, and will also produce circumferential scoring of the shaft in the seal area.

What causes a seal to fail on a hydraulic motor?

Seal failure on the hydraulic motor is usually caused by excess pressure build-up in the motor casing. Some other common causes: Not connecting the quick disconnect fitting completely on the wing style fittings. Hooking up the pressure line before the return line causing the pressure in…

What causes seals on a centrifugal pump to fail?

In a horizontal, end suction centrifugal pump, frequent and regular seal failure with different seals indicates an undersized shaft subjected to excessive deflection.

What causes air to enter a piston pump shaft?

Air may be entering around the pump shaft seal. Gear and vane pumps which are pulling suction oil from a reservoir located below them, will have a slight vacuum behind the shaft seal. When this seal becomes badly worn, air may enter through the worn seal. Piston pumps usually have a small positive pressure, up to 15 PSI, behind the shaft seal.

What causes a C-face pump shaft seal to fail?

The new system developed a problem with the C-face mounted pump shaft seal failing after six weeks or so. The seal lip with a garter spring was pushed out. The maintenance crew replaced the seal and was told by the power-unit builder that this type of failure was normally due to excessive pump case pressure.

What causes a shaft seal to go out?

The seal lip with a garter spring was pushed out. The maintenance crew replaced the seal and was told by the power-unit builder that this type of failure was normally due to excessive pump case pressure. The crew installed a standard 0- to 300-psi pressure gauge teed into the case line to monitor case pressure.

What causes a hydraulic pump shaft to wear out?