Product Overview
The MK04-2-11A-K04-3340-3FP0 (Poclain identification code A44874B) is a radial piston hydraulic motor from the Poclain Hydraulics MK compact motor series, MK04 frame size. The motor employs a radial piston cam-lobe design, integrating high torque output into an exceptionally compact housing, making it ideal for wheel motor or tool drive applications. The MK04 series offers a maximum displacement of 408 cc/rev, maximum power of 18 kW (24 HP), maximum torque of 2600 N·m (1918 lb-ft), maximum working pressure of 400 bar (5,802 PSI), and maximum speed of 120 rpm.
The MK04-2-11A-K04-3340-3FP0 offers a displacement of 408 cm³/rev, theoretical torque of 649 N·m (330 lb-ft) at 100 bar, weight of approximately 31 kg, and integrated parking brake as standard.The MK04 series is specifically designed for road rollers, with its compact direct-drive design making it ideal for wheel motor or tool drive applications, and also suitable for mining, agriculture, environmental, and other markets.
The model code decodes as: “MK04” = MK compact series 04 frame size, “2” = second-generation design, “11A” = ISO 11926-1 port connection standard, “K04” = integrated brake configuration, “3340” = wheel-mount interface configuration code, “3FP0” = additional function and seal/brake configuration code.
Series-Related Models: MKD04 is a dual displacement variant with maximum displacement of 545 cc/rev and maximum power of 18 kW.MKE04 is the integrated brake variant frame.MK18 is the large displacement frame size in the MK series, covering displacements from 1395 to 2812 cc/rev, maximum power of 70 kW, maximum torque of 17900 N·m, maximum speed up to 160 rpm, and working pressure range of 400–450 bar.
The motor offers complete interchangeability: mounting flange, output shaft, and port configuration are identical to the original Poclain specification, enabling drop-in replacement without hose or bracket modification. Every unit undergoes 100% simulated duty-cycle testing before shipment.
Technical Specifications
MK04-2-11A-K04-3340-3FP0 (Primary Model)
Model: MK04-2-11A-K04-3340-3FP0
Poclain Identification Code: A44874B
Brand Series: Poclain Hydraulics MK Series / MK04
Motor Type: Radial piston compact, fixed displacement, low-speed high-torque
Displacement: 408 cm³/rev (24.9 cu.in/rev)
Theoretical Torque (@100 bar): 649 N·m (330 lb-ft)
Maximum Output Torque: 2600 N·m (1918 lb-ft)
Maximum Working Pressure: 400 bar (5,802 PSI)
Maximum Power: 18 kW (24 HP)
Maximum Speed: 120 rpm
Port Connection: ISO 11926-1 (11A configuration)
Integrated Brake: Standard (parking brake)
Rotary Group Inertia: 0.028 kg·m²
Mounting Type: Wheel mount / shaft mount
Weight: Approximately 31 kg
Operating Temperature Range: -20°C to +80°C (reference: MK series general data)
Note: Parameters are compiled from Poclain official technical documentation and publicly available supplier technical data.
MK04 Series Displacement Variants (Series Reference)
MK04 displacement 272 cm³/rev: Theoretical torque 432 N·m @100 bar, max power 18 kW, max speed 120 rpm
MK04 displacement 340 cm³/rev: Theoretical torque 541 N·m @100 bar, max speed 110 rpm
MK04 displacement 408 cm³/rev: Theoretical torque 649 N·m @100 bar, max speed 100 rpm (primary model displacement)
Note: Theoretical torque and maximum speed data for the three MK04 series displacement variants are sourced from the Poclain official technical datasheet.
MKD04 Dual Displacement Variant (Series Reference)
Model Frame: MKD04
Maximum Displacement: 545 cc/rev
Maximum Power: 18 kW (24 HP)
Maximum Torque: 3470 N·m
Maximum Working Pressure: 400 bar
Features: Dual displacement design for travel drive applications requiring speed switching
MKE04 Integrated Brake Variant (Series Reference)
Model Frame: MKE04
Displacement Range: Reference MK04/MKD04 equivalent specifications
Maximum Working Pressure: 400 bar
Maximum Power: 18 kW
Integrated Brake: Standard multi-disc parking brake / service brake
MK18 Large Displacement Frame (Series Reference)
Model Frame: MK18/MKE18
Displacement Range: 1395–2812 cc/rev
Maximum Power: 70 kW (94 HP)
Maximum Torque: 17900 N·m
Maximum Working Pressure: 400–450 bar
Maximum Speed: 160 rpm
Key Technical Advantages
① Radial Piston Cam-Lobe Design — High Power Density with Compact Structure
The MK04-2-11A-K04-3340-3FP0 utilizes Poclain‘s tried and tested radial piston cam design, which is continually being improved. Working cylinders arranged radially around a crankshaft deliver torque up to 2600 N·m at extremely low speeds without requiring reduction gearing. MK series motors combine high power density with compact dimensions, achieving 18 kW of power output within a housing weighing only 31 kg. For road roller vibratory drum drives, skid steer loader wheel drives, and similar applications, this design minimizes installation space requirements while maintaining high torque output.
② Ultra-Short Structural Design with Large-Diameter Four-Point Contact Ball Bearing — Accommodates Constrained Installation Spaces
The MK04 series features an ultra-short structural design with a large-diameter four-point contact ball bearing, compressing the motor’s axial dimensions to the extreme. The four-point contact ball bearing simultaneously accommodates radial and axial combined loads, offering significant advantages in road roller vibratory drum drives and other applications with combined radial and axial loading. The ultra-short structure enables direct integration of the motor into wheel hubs or tool drive shafts, significantly reducing overall drivetrain dimensions. Poclain official documentation states that MK motors are “particularly suited for mounting on vibratory equipment, thanks to their large central hollow shaft design.”
③ Integrated Brake System — Safe Parking and Smooth Braking
The MK04-2-11A-K04-3340-3FP0 is equipped with an integrated parking brake as standard, featuring a multi-disc brake structure. The negative brake design automatically engages the brake in the event of hydraulic pressure loss or failure, effectively preventing rollback on slopes. The integrated brake system simplifies external piping and installation footprint while enhancing system safety and reliability. For road rollers and other equipment requiring operation and parking on slopes, this configuration significantly improves operational safety.
④ High Resistance to Variable Loads and Long-Life Design
MK04 series motors feature a reinforced housing structure specifically designed to withstand high variable loads and shock loads, suitable for high-impact operations such as road roller vibratory compaction. High-strength castings with internal reinforcement ribbing enhance overall casing rigidity and deformation resistance. The large-diameter four-point contact ball bearing offers load capacity far exceeding conventional bearing configurations, effectively preventing premature bearing failure in heavy-duty applications such as road roller travel drives, extending motor overhaul intervals.
⑤ Broad Interchange Compatibility and Series Selection
The MK04-2-11A-K04-3340-3FP0‘s standardized mounting interface (ISO 11926-1 port connection) allows direct replacement of equivalent Poclain original motors. The MK compact motor series offers complete displacement coverage from MK04 (408 cc) to MK18 (2812 cc), enabling users to precisely select displacement size based on specific application torque, speed, and flow requirements. Standardized interface design maintains mounting compatibility across different displacement sizes within the same series, facilitating equipment upgrades or displacement adjustments. The MK series also offers optional speed sensors (T4/TR/TD types) for closed-loop control systems.
Application Areas
Compaction Equipment (Primary Application): Bomag BW120 AD-3, BW138 AD, BW154 and similar vibratory road roller travel drives; Dynapac, Caterpillar road rollers
Construction Equipment: Mini excavators, skid steer loaders, compact wheel loaders
Mining Equipment: Underground LHDs, mining truck travel drives
Agricultural Machinery: Tractors, combine harvesters, seeders
Material Handling: Forklifts, telehandlers, port tractors
Railway Equipment: Track maintenance vehicle travel drives
Environmental Equipment: Municipal sweepers, garbage compaction trucks
Industrial Applications: Compact hydraulic transmission systems requiring low-speed high-torque direct drive
Expert Maintenance Tips
Pre-Installation Inspection: Verify flatness and cleanliness of the mounting flange mating surface; check thread condition of mounting bolt holes. For wheel-mount (3340 configuration) applications, ensure wheel hub-to-output flange coaxiality within 0.05 mm; excessive misalignment causes bearing edge loading and premature seal wear. Use bolts of strength class 8.8 or higher, tightened in diagonal sequence to specified torque.
First Commissioning: The motor casing must be filled with clean hydraulic oil before initial start-up. Poclain official technical documentation explicitly states: “Very important: Fill the motor body with oil through its drain port before start-up.”Fill through the highest casing port until oil overflows from the level port. Dry starting causes metal-to-metal contact between piston-to-cam ring surfaces and the valve plate without lubrication, resulting in irreversible damage. For MK04 models equipped with integrated brakes, confirm the brake circuit has been properly bled to avoid delayed brake release.
Fluid Cleanliness: Maintain system oil cleanliness at NAS 8 (ISO 4406 18/16/13) or better. The radial piston motor’s valve plate and piston pairs are sensitive to particulate contamination; excessive contamination accelerates wear and causes volumetric efficiency degradation. Inspect return filter elements regularly and replace per the machine manufacturer‘s recommended interval.
Scheduled Inspection: Check casing drain flow and brake clearance every 500 operating hours. Under normal conditions, drain flow should remain stable; a sustained increase indicates accelerated wear of piston pairs or valve plate surfaces, and preventive maintenance should be scheduled. Inspect the output flange area for oil seepage; replace seals at the first sign of degradation. For road roller applications, pay particular attention to mounting bolt tightness under vibratory conditions, periodically rechecking torque.
Long-Term Storage Protection: If the motor will be idle for more than 3 months, fill the casing with rust-preventive hydraulic oil and manually rotate the shaft several turns monthly to prevent corrosion or adhesion on piston-to-cam ring interfaces and valve plate surfaces. Perform a no-load run-in before returning to service.
