MS25-2-G21-F42 Poclain Hydraulic Motor | Two Speed Brake

Product Overview

The MS25-2-G21-F42-1510-00-MR is a Poclain Hydraulics MS-series multi-purpose radial piston hydraulic motor configured with two-speed variable displacement and an integrated multi-disc wet brake. The MS series employs a modular design concept covering displacements from 172 cc/rev to 15,000 cc/rev, making it ideal for wheel-end or tool-end direct drive applications. The MS25 frame size delivers a maximum displacement of 3006 cc/rev, up to 90 kW of power, 21,500 N·m maximum torque, 450 bar peak pressure and 145 rpm maximum speed, with multi-speed design for demanding applications.

The model code breaks down as follows: MS25 identifies the frame size; 2 denotes two-speed variable configuration; G21 is the flow-distribution shaft module; F42 is the brake module; 1510 is the wheel/shaft output-end configuration; 00-MR denotes rotation and additional options.

Every unit undergoes 100% simulated operating-condition bench testing prior to shipment. Mounting flange, shaft end and port dimensions are identical to the original Poclain MS25 series, enabling true drop-in interchangeability with zero modification to the installation interface.

Technical Specifications

• Series: MS25

• Model Code: MS25-2-G21-F42-1510-00-MR

• Type: Radial piston LSHT hydraulic motor

• Displacement Range: 2004–3006 cc/rev (MS25 series)

• Max Displacement: 3006 cc/rev (183.4 cu.in/rev)

• Max Torque: 21,500 N·m (15,857 lb-ft)

• Max Peak Pressure: 450 bar (6,527 psi)

• Max Continuous Pressure: 250 bar

• Max Power: 90 kW (121 HP)

• Max Speed: 145 rpm

• Control Type: Two-speed variable displacement

• Brake Type: Integrated multi-disc wet brake (service + parking)

• Weight: ~180–210 kg

• Motor Type: Wheel motor / shaft motor (modular)

• Anti-Skid Option: TwinLock™ available

Key Technical Advantages

1. Two-Speed Variable Control for Wide Operating Range

The MS25-2 configuration features a two-speed variable design with an on-line shift mechanism in the flow-distribution shaft. The low-speed/high-displacement mode delivers maximum torque for heavy-duty startup and grade climbing; the high-speed/low-displacement mode reduces system flow demand during light-load cruising, improving travel speed and fuel efficiency. The G21 flow-distribution module enables smooth, shock-free shifting under hydraulic pilot control.

2. Integrated Multi-Disc Wet Brake (F42 Module)

The F42 brake module combines service brake and parking brake functions in a single integrated unit. Brake release pressure is typically 14 bar (203 psi) and must not exceed 30 bar (435 psi). The brake employs a hydraulically released, spring-applied fail-safe design that automatically locks when system pressure is lost, ensuring safe machine parking. Static brake torque can be verified before installation to confirm factory performance.

3. Modular Architecture for Maximum Adaptability

The MS series modular design allows displacement group, flow-distribution module, brake module and output-end module to be reconfigured without structural modification to the host machine. The 1510 output-end configuration supports both wheel-drive and shaft-output mounting, enabling a single motor platform to serve wheel loaders, self-propelled sprayers, harvesters and more.

4. High-Precision Cam Ring and Long Service Life

The MS25 cam ring is manufactured from high-hardness alloy steel with a working surface hardness of 60–62 HRC. Precision grinding ensures resistance to high-frequency contact fatigue from piston rollers. A hydrodynamic oil film forms between rollers and cam ring, significantly reducing wear rate and extending overhaul intervals.

5. 100% Simulated Load Testing & Drop-In Interchangeability

Each motor is bench-tested under simulated operating conditions prior to dispatch, covering pressure cycling, speed shifting, brake performance and thermal variation. Mounting flange, shaft end and port dimensions match the original Poclain MS25 series exactly, enabling direct replacement without pipework or interface modification.

Application Areas

The MS25 series is widely deployed in heavy-duty travel and tool drives, with OEM installation on Caterpillar, Volvo CE, Komatsu, JCB, Case, John Deere, Claas and other major equipment platforms:

• Wheel Loaders: Caterpillar 966H/972K, Volvo L150G/L180H, Komatsu WA470/WA500, JCB 457/467, Case 921G/1021G

• Self-Propelled Sprayers: John Deere 4940/R4030, Case IH Patriot 4430/4440, New Holland Guardian SP410F, Fendt Rogator 900, Amazone Pantera 7004, Agrifac Condor Endurance, Hardi Alpha 5100

• Harvesters: Claas Lexion 8700/8800

• Others: road rollers, mining dump trucks, forestry forwarders, industrial material handling equipment

Expert Maintenance Tips

1. Static Brake Torque Verification: Perform static brake torque testing before mounting the motor on the machine. Connect the X brake feed port to the pressure source, the A port to supply, and the R port to the tank. Leave the Y two-speed shift spool port and the 1 drain port open to air. Brake release pressure must be maintained between 14–30 bar. After the test, confirm release pressure returns to zero, then gradually increase motor main supply pressure to the limit value specified in the technical manual to verify brake torque.

2. Two-Speed Shift System Maintenance: Two-speed shifting is controlled by pilot pressure on the flow-distribution shaft. Shift pressure should be set per the technical manual. If shift response is sluggish or excessively harsh, inspect the pilot control spool for sticking and the flow-distribution shaft O-rings for aging. Shift operations should be performed at low speed or standstill to avoid impact loading on the distribution mechanism.

3. Brake Wear Monitoring: Periodically inspect multi-disc wet brake friction plate thickness and spring preload. Abnormally high brake release pressure (exceeding 30 bar) typically indicates friction plate wear or piston seal failure—replace friction plates and seals promptly. During reassembly, coat the piston seal contact surface, spring washer and snap ring grooves with anti-oxidizing grease.

4. Oil Cleanliness and Temperature Control: Maintain system oil cleanliness at ISO 4406 18/16/13 or better. Operating oil temperature should be kept below 80°C; elevated temperatures accelerate brake friction plate and seal degradation. Replace hydraulic oil and filter after the first 500 hours of operation, then follow a 2,000-hour or annual replacement cycle.

5. Drain Line Management: The drain port must return to the reservoir independently—housing back pressure must not exceed 2 bar. The drain line end must remain submerged to prevent air ingestion. After extended shutdown, fill the housing with clean hydraulic oil before restarting.