Noise, low flow or vibration does not identify a worn pump part by itself. On an A10VSO Series 31 unit, the same symptom may involve air bleeding, suction conditions, the drive, the control system or mechanical damage. Start with the exact pump designation and evidence from the installed system before deciding what to replace.
This guide identifies the main assemblies, explains what to record during troubleshooting and sets out the information needed for a parts review. It gives no universal wear limits. Reuse or replacement decisions require inspection criteria for the particular unit. The main source is Bosch Rexroth instruction manual RE 92701-01-B/04.2018, which covers A10VO and A10VSO Series 31. The linked copy is hosted by a third party. Check the current manufacturer documentation, the applicable data sheet and the order confirmation for the installed unit. Bosch Rexroth manual, §§1.1–1.2 and 14 (third-party-hosted copy)
About this guide: Guangdong Sheungchak Hydraulic Technology Co., Ltd. publishes this page and lists A10VSO pumps on its site. The component names and ordering examples below also draw on Anfield's 2025 replacement-parts catalogue. This article does not report a teardown, measurements or verified availability of individual repair parts from Sheungchak. The linked Sheungchak product page describes complete pumps; individual parts require a separate supplier and configuration review.
Confirm the exact Series 31 unit
Photograph the complete nameplate. Record the full type code, material number, serial number and direction of rotation. Rotation is viewed from the drive-shaft end: R is clockwise and L is counter-clockwise. The plate's direction must match the drive motor. Also document the installed
controller, shaft, ports and any through drive. "A10VSO71/31" alone is not enough to specify a spare part: Rexroth says its spare-parts lists are order-specific and asks for the unit's material and serial numbers and the requested parts' material numbers. Compare the nameplate with the order confirmation when available. Bosch Rexroth manual, Fig. 3, Fig. 10 and §§7.4.1, 10.5
If the plate is unreadable, photograph the remaining markings and the pump's mounting and connection interfaces. Treat a proposed match as provisional until a qualified provider checks it against the unit's records. Our hydraulic pump nameplate guide explains the identification workflow.
Identify the assemblies before naming a replacement
Rexroth's layout drawing and functional description explain how the pump works. Anfield's own replacement-parts catalogue uses some different commercial names and lists rotary-group subcomponents; it says to contact sales before ordering some individual items. The table below helps translate those names; it does not indicate which part has failed or establish another supplier's stock. Bosch Rexroth manual, Fig. 2 and §5.2.2; Anfield Series 31 service-parts list, p. 2, size tables and p. 14
| Assembly or term | What it means in a parts discussion |
|---|---|
| Rotary group | In Anfield's catalogue, this group includes piston/shoe assemblies, a retaining plate, cylinder block and retaining hardware. Rexroth's description explains that the shaft turns the cylinder and the pistons stroke in its bores. |
| Control plate / valve plate | Rexroth calls it the control plate or distributor plate; Anfield calls its replacement item a valve plate or lens plate. Its slots route fluid to and from the piston chambers. |
| Cradle / swash plate | The cradle's angle changes piston stroke and pump displacement. Anfield calls the corresponding assembly a swash plate and lists a separate saddle bearing kit. |
| Drive shaft and bearings | The shaft transmits drive torque to the rotary group. Anfield lists front and rear shaft bearings separately; a noise or vibration complaint still requires the drive and installation to be checked. |
| Controller and control pistons | The installed control arrangement governs displacement. Confirm its exact version before comparing replacement items. Do not assume that similarly named pistons in different documents are interchangeable. |
| Seals | Identify the seal location and required material before requesting a kit. Anfield, for example, lists separate nitrile and FKM kits; that is a choice in its catalogue, not a universal kit specification. |
A drawing helps name a component. It cannot establish damage, acceptable reuse or the scope of a repair.
Investigate symptoms before declaring internal wear
Only authorized personnel should troubleshoot within the safety area designated by the machine manufacturer. Hydraulic components can remain pressurized; the relevant system must be depressurized under the machine manufacturer's instructions before lines or components are disconnected. Rexroth manual, §§2.6, 11.2 and 14
| Observation | Record before specifying a part | First checks from Rexroth's instructions |
|---|---|---|
| New or unusual noise | When it occurs; fluid and operating temperature; suction-line changes; recent drive, coupling or mounting work. | Review filling and air bleeding, suction conditions and drive speed; an increase in noise or bubbles in the drain fluid can indicate insufficient fluid supply (§8.1.2; Table 14). |
| Reduced or unstable flow or pressure | The operating condition and readings; drive condition; installed controller; recent system changes. | Review air bleeding, suction-line restrictions, fluid viscosity, rotation, drive and control conditions before attributing the symptom to wear (Table 14). |
| Increased vibration | Where it is observed and whether the drive, mounting and coupling have been assessed. | Check drive and coupling alignment and mounting; worn bearings are a reason to contact Bosch Rexroth Service, not a diagnosis from vibration alone (§7.4.4; Table 14). |
| Visible leakage | Its location and operating conditions. A photograph alone cannot establish the failed seal or an internal cause. | Review torsional vibration, speed variation and any belt or cardan-shaft drive that could affect the shaft seal (§§7.4.3, 7.4.6). |
Rexroth's malfunction table lists insufficient air bleeding, suction problems, incorrect rotation, drive faults, control faults and mechanical damage among possible causes. It is a troubleshooting list, not a ranking of failure frequency. Rexroth manual, Table 14
The manual also gives checks with defined conditions. It specifies at least 0.8 bar absolute at suction port S during operation; maximum speed values in the data sheets are stated for 1 bar absolute at that port. For hydraulic fluid, it specifies a minimum ISO 4406 cleanliness level of 20/18/15, or 19/17/14 when viscosity at the drain port is below 10 mm²/s. These are operating and fluid requirements for the manual's stated units, not internal-part wear limits. Check the applicable data sheet and order confirmation for the specific pump: the manual identifies RE 92711 for A10VSO and RE 92701 for A10VO. Bosch Rexroth manual, Table 1 and §§7.2, 8.1.1
For maintenance records, Rexroth's inspection schedule calls for daily checks for leakage and unusual noise, and fluid analysis yearly or every 2,000 operating hours, whichever comes first. After the running-in phase of about 10 operating hours, it recommends checking a fluid sample for the required cleanliness level. These are inspection and fluid checks, not a schedule for replacing every bearing, seal or rotary-group component. Rexroth manual, §§8.2 and 10.2
Decide the inspection and replacement scope
Use this sequence before choosing a replacement:
- Record the operating conditions, fault history and system changes; check the relevant system-side causes in Rexroth's malfunction table (§14.1; Table 14).
- If evidence points to wear or mechanical damage of the axial piston unit, follow Rexroth's remedy: replace the unit and contact Bosch Rexroth Service. For vibration attributed to worn bearings, contact Bosch Rexroth Service. Repair of the unit and assembled parts should be performed by certified service centers (§10.4; Table 14).
- Once a qualified provider has confirmed the unit's configuration and any repair scope, request the exact parts list and inspection criteria before selecting a component (§10.5; Table 14).
If a qualified inspection confirms pump damage, document the affected assembly, its mating surfaces and the criteria used to decide whether any part can be reused. Do not turn a parts catalogue into a default replacement bundle.
These are Rexroth's instructions for its units; they do not establish an inspection threshold for ordering one internal component. Bosch Rexroth manual, §10.4 and Table 14
A fixed bearing replacement hour count would also be misleading. Rexroth says unit service life is limited by bearing life, which depends on the load cycle; the system manufacturer should determine the bearing replacement interval for the maintenance schedule. Rexroth manual, §10.3
Confirm kit contents, configuration and repair requirements
Ask the proposed supplier for an exact bill of materials, part identifiers and exclusions. In Anfield's 2025 catalogue, ordering its complete rotary group requires a valve plate selected separately for the pump's rotation; some individual rotary-group items are subject to availability. This is an example of why "rotary group" alone does not define what arrives in a kit. Anfield Series 31 service-parts list, notes and p. 14
Check the shaft, port arrangement, through-drive code and seal material against the actual unit. Anfield's catalogue distinguishes rear-port 61N00 and side-port 62N00 end covers and lists nitrile and FKM seal kits. Separately, Rexroth's storage instructions call for shaft-seal replacement when storage exceeds 24 months; that storage condition is not a general operating-life rule for seals. Anfield Series 31 service-parts list, pp. 2–3; Rexroth manual, §6.2
Keep supplier compatibility claims separate from manufacturer approval. Anfield describes its replacements as interchangeable. Rexroth's manual says unsuitable spare parts can cause injury or property damage and instructs users repairing Rexroth units to use original Rexroth parts; it warns that functional reliability otherwise cannot be guaranteed and the warranty will be voided. Confirm the technical requirements and applicable warranty position for the exact unit before purchasing. Anfield Series 31 service-parts list; Rexroth manual, §§10.4–10.5
What to send for a technical review
Give the reviewer enough information to identify both the pump and the fault:
- A legible photograph of the complete nameplate, including the material and serial numbers.
- Photographs of the installed pump, shaft, ports, controller and any through drive.
- The order confirmation and installation drawing, if available.
- The symptom, when it occurs and the relevant operating readings.
- Recent maintenance, fluid and filter findings, and changes made before the symptom appeared.
- Any inspection report, including the suspected assembly, measurement method and finding.
Rexroth identifies the order confirmation as the source of order-related technical data and the installation drawing as the source of dimensions and connections. Its troubleshooting guidance also asks for operating history and changes to the wider system. A technical review should establish the configuration and next inspection step before a part name becomes an order. Rexroth manual, Table 1 and §§10.5, 14.1
Send the nameplate, configuration and symptom records to info@hydraulicsc.com for a configuration inquiry; the evidence may still require review by the machine manufacturer or a qualified service provider. If a complete pump replacement is being considered, see Sheungchak's A10VSO pump page for its listed pump offering. That page does not establish availability of individual repair parts or Bosch Rexroth authorization.
