Rexroth Core Series Part III: Extended HPS Repair Capabilities

rexroth repair

Note on this series: This is the third in our Rexroth Core Series, spotlighting high-demand Rexroth components and how Hydraulic Parts Source (HPS) supports distributors, rebuilders, and service teams through core purchasing and supply. In Part 1, we discussed popular pump models like the A4V, A6, A10V, and SYDFE. In Part 2, we covered motors like the A2F and directional control valves (DCVs) such as the 4WE6 and 4WE10. In Part 3, we go deeper into our in-house repair capabilities for Rexroth piston pumps, and servicing models like the A4V, A6, and SYDFE.

For distributors, supporting customers goes beyond supplying new parts—it’s about keeping equipment running with reliable, cost-effective solutions. That’s where HPS repair capabilities for Rexroth piston pumps come in. By offering repair options for A4V, A6, and SYDFE cores, distributors can provide their customers with faster turnaround, lower costs compared to new units, and confidence that their equipment will perform to OEM standards.

This third installment in our Rexroth Core Series highlights how HPS handles the inspection, repair, and testing of these complex pumps and controls. With a trusted repair partner, distributors can deliver added value to customers who depend on Rexroth performance in critical applications — helping them reduce downtime, extend the life of their equipment, and strengthen trust in their distributor relationship.

HPS Repair on Rexroth Cores

Today, we take you behind the scenes at HPS: detailing our in-house repair capabilities and what it takes to bring A4V, A6, and SYDFE cores back to OEM performance.

But before jumping into specifics per model line, here are the core principles and capabilities that define repair at HPS:

Full teardown and inspection – Every core get completely disassembled. Wear, scoring, corrosion, and dimensional degradation are all assessed.
OEM / OEM-equivalent parts – We use genuine Rexroth parts where available, or high-quality equivalent replacements that meet or exceed original specs.
Precision machining – Cylinder blocks, shafts, compensators, housings, etc., are machined to tight tolerances. Surface finishes restored.
Seal, piston, valve plate refurbishment – Seal kits, piston kits, spools, and control plates are replaced or reconditioned.
Control / electronics work (for SYDFE) – SYDFE’s electro-hydraulic control components require calibration, testing, and sometimes replacement of sensors, feedback devices, and electronics.
Rigorous testing – We test repaired cores under load, pressure, and flow to ensure that performance, leakage, and response meet specification.

A4V Series Repair Capabilities

The A4V series — variable axial piston pumps — are among the most demanding in terms of pressure, flow, and durability.

Repair work here has its specific challenges, and HPS’s capability set has them covered.

A6 Series Repair Capabilities

The A6 series pumps/motors (often in bent-axis designs, closed circuits) are compact, high-speed units. Repairing these requires attention to precision and tolerances.

Key repair work for A6 includes:

SYDFE System Repair Capabilities

The SYDFE control system (electro-hydraulic) combines a Rexroth pump (often A4V or similar) with advanced control, sensors, feedback, etc. Repairing SYDFE cores involves mechanical and electrical / control restoration:

Mechanical pump repair as above (swashplate, cylinder block, pistons, etc.).
Electro-hydraulic control unit inspection: electronics, sensors (angle, pressure), wiring, connectors.
Calibration / tuning: Ensuring the pump response (swivel angle vs command signal), pressure compensation, control ramp times, etc., match the factory or specified curves.
Diagnostic testing: Software or hardware based, checking for drift, latency, hysteresis in control, response under load.
Control valve / proportioning hardware: Rebuild or replace spool valves, slide valves or proportional valves associated with SYDFE.

Because SYDFE adds more failure modes (electronics, sensors), HPS maintains both mechanical and electrical test benches to verify full system behavior, not just mechanical output.

Why HPS’s Repair Capabilities Matter

Putting repaired cores back in service is more than “just saving money.” Here are strategic benefits:

Reduced Downtime – Faster turnaround vs ordering new OEM units.
Cost Efficiency – Repairing cores often is significantly cheaper than replacing, especially with large, high pressure units.
Sustainability & Inventory Management – Utilizing cores and refurbishment reduces waste and allows stock of repair-ready cores.
OEM-level performance restored – With precision work, performance (flow, pressure, efficiency) is restored, maintaining system reliability.

For distributors, having a dependable repair resource like HPS means you can offer more than just parts — you can provide complete solutions. When your customers face downtime with their A4V, A6, or SYDFE Rexroth pumps, you can confidently connect them to repair services that restore OEM-level performance and extend the life of their equipment.

By partnering with HPS, distributors strengthen their customer relationships, reduce costly delays, and position themselves as trusted problem-solvers in a competitive market.