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Use this hydraulic pump incoming inspection checklist to verify order configuration, shipping condition, ports, documents, and test evidence before installation.

Hydraulic pump power is calculated from pressure difference and flow; required shaft input is higher after efficiency is included. Use consistent units, distinguish gauge pressure from pressure difference, and size the driver for the real d

Pump temperature rise is a symptom of energy loss or heat arriving from the system, not proof that the pump is defective. Separate local housing temperature, inlet oil temperature, outlet oil temperature, case-drain temperature, pressure, f

A volumetric-efficiency test compares measured delivery with the theoretical flow from displacement and speed at documented pressure and temperature. The result is useful only when instrument accuracy, leakage boundaries, oil condition, con

A case-drain line must carry expected leakage with sufficiently low back pressure in the worst temperature and transient conditions. Diameter alone is not enough: length, elevation, fittings, shared returns, reservoir entry, oil viscosity,

Pump case pressure is the pressure inside the housing relative to its drain destination. Excess pressure can load shaft seals, change internal leakage paths, and damage the rotating group. Measure it at the specified point during cold start

High standby pressure may come from an incorrect control setting, a false load-sense signal, a blocked or damped signal line, valve-center mismatch, excessive return pressure, contamination, or a pump-control fault. Preserve the settings an

Load-sensing margin is the pressure difference the pump control maintains between pump outlet pressure and the sensed load signal under defined conditions. Measure both pressures at the same time. A single outlet gauge cannot show whether t

A pressure compensator changes pump displacement as outlet pressure approaches its setting; it is not a substitute for the system relief valve. Adjustment requires a confirmed schematic, calibrated pressure measurement, an established relie

Shaft runout is the indicated radial movement observed while the shaft rotates. Measure it with the pump safely isolated, a stable fixture, a clean reference surface, and a documented measurement location. Compare only with the manufacturer

Hydraulic pump ports must be identified by thread form, diameter, pitch, sealing method, port standard, and pressure duty. SAE O-ring boss, BSPP, NPT, and metric ports may appear close in size but seal differently; forcing a near match can

A two-bolt or four-bolt label does not fully identify a hydraulic pump mounting flange. Pilot diameter and length, bolt circle, hole size, shaft location, mounting face, allowable loads, and the applicable drawing must all match. Use the co