Product Overview
The MKE18-1-A21-F19-1340-8000 is a high-performance compact radial piston hydraulic motor from the Poclain Hydraulics MK/MKE18 Series. The MK18/MKE18 Series represents the highest power class within the Poclain MK compact motor platform, achieving a maximum displacement of 2,812 cc/rev, maximum power of 70 kW (94 HP), maximum torque of 17,900 Nm, and high speeds up to 160 rpm. The series is specifically designed for compactor wheel drive applications, while also being widely deployed in mining, agricultural, and environmental equipment for wheel drive or tool drive systems.
The MKE18-1-A21-F19-1340-8000 belongs to the “1” displacement group within the MK18/MKE18 Series, with a full displacement of 1,911 cc/rev in a single displacement configuration. Model code breakdown: MKE18 designates the MK18/MKE18 compact radial piston motor series; 1 indicates the displacement group (1,911 cc/rev); A21 specifies the mounting flange and shaft configuration; F19 defines port location and connection specification; 1340 specifies the control and valve body configuration; and 8000 indicates the special option configuration. The motor is manufactured to original Poclain Hydraulics specifications with 100% drop-in interchangeability, requiring no modification to mounting interfaces, port positions, or hydraulic connections. Every unit undergoes 100% simulated operating condition testing at the factory, including rated pressure loading, volumetric efficiency verification, seal integrity assessment, and low-speed smoothness validation prior to shipment.
Technical Specifications
MKE18-1-A21-F19-1340-8000:
Series / Type: Poclain MK18/MKE18 Series compact radial piston hydraulic motor
Displacement group: Displacement Group 1
Full displacement: 1,911 cc/rev (116.6 cu.in/rev)
Design: Radial piston cam-lobe design, working cylinders radially arranged around crankshaft
Maximum working pressure: 450 bar (6,527 psi)
Maximum torque: 17,900 Nm (13,202 lb-ft)
Maximum power: 70 kW (94 HP)
Maximum speed: 160 rpm
Direction of rotation: Bidirectional
Mounting: Wheel flange mount
Anti-skid: TwinLock™ integrated anti-skid system compatible
Brake: Parking brake option available
Bearing arrangement: Large diameter 4-contact roller bearing
Housing material: High-strength cast iron
Approximate weight: 96 kg (may vary with configuration options)
MK18/MKE18 Series displacement range (for reference):
MK18-8: 1,395 cc/rev, semi 697 cc/rev
MK18-9: 1,571 cc/rev, semi 785 cc/rev
MK18-0: 1,747 cc/rev, semi 873 cc/rev
MK18-1: 1,911 cc/rev, semi 955 cc/rev
MK18-2: 2,099 cc/rev, semi 1,049 cc/rev
MKE18-0: 2,340 cc/rev, semi 1,170 cc/rev
MKE18-1: 2,560 cc/rev, semi 1,280 cc/rev
MKE18-2: 2,812 cc/rev, semi 1,406 cc/rev
Note: MK18 is the single displacement configuration; MKE18 is the dual displacement configuration. The MK18/MKE18 Series covers displacements from 1,395 to 2,812 cc/rev, with maximum working pressure of 400 to 450 bar, maximum torque of 17,900 Nm, maximum speed of 160 rpm, and maximum power of 70 kW. For precise technical specifications of the MKE18-1-A21-F19-1340-8000, always consult the official Poclain Hydraulics technical manual or the product nameplate data.
Key Technical Advantages
1. Radial Piston Cam-Lobe Principle for High Starting Torque
The MKE18-1 employs Poclain’s signature radial piston cam-lobe architecture, with working cylinders arranged radially around the crankshaft and pistons converting radial force into crankshaft rotational torque through the cam ring. The engineering advantage of this design lies in the direct application of piston force to the crankshaft eccentricity, maximizing the moment arm and enabling extremely high starting torque even at very low speeds. Unlike axial piston motors, the radial piston design delivers maximum torque instantaneously upon startup without requiring oil film pressure build-up, making it ideally suited for wheel drive applications involving frequent start-stop cycles and heavy-load starting.
2. Large Diameter 4-Contact Roller Bearing for High Load Capacity
The MK18/MKE18 Series employs a large diameter 4-contact roller bearing arrangement, capable of simultaneously accommodating significant radial and axial external loads. The engineering advantage of this bearing configuration lies in its ability to directly absorb radial forces generated by wheel hubs or driven tool components without requiring a separate bearing support housing — simplifying system design and reducing installation costs. Compared to conventional bearings, the 4-contact roller bearing offers higher load capacity and longer service life, performing particularly well under frequent start-stop and shock load conditions.
3. Compact Direct Drive Design with High Power Density
The MK18/MKE18 Series features a compact direct drive design, achieving 1,911 cc/rev displacement capability within a compact housing, with maximum power up to 70 kW — a power density that leads its class among low-speed high-torque radial piston motors. The motor can be installed directly within wheel hubs (wheel drive applications), with output shaft bearings accommodating simultaneous radial and axial external loads, eliminating the need for separate bearing support housings. The compact structure enables high torque output within limited installation space — particularly important for compactors, mini loaders, and other space-constrained applications.
4. Modular Design for System Integration Flexibility
The MK18/MKE18 Series features a highly modular design with flexible configuration options for wheel flanges, shaft ends, brake types (parking brake), and the TwinLock™ integrated anti-skid system. The engineering value of the modular architecture lies in its ability to achieve different functional configurations by replacing end cap modules rather than the entire motor. For equipment manufacturers requiring multiple drive configurations, this design significantly simplifies spare parts management and system integration complexity. The TwinLock™ anti-skid function effectively prevents vehicle rollback on slopes or low-traction surfaces, enhancing machine safety.
Application Areas
Road construction and maintenance: Vibratory roller wheel drives (Bomag, Dynapac, SDLG and comparable brands), the series is specifically designed for compactor drive applications
Mining machinery: Mining mini loaders, underground transport vehicle drives
Agricultural machinery: Tractor wheel drives, combine harvester ground drives, self-propelled sprayers
Environmental equipment: Sanitation vehicle travel drives, street sweeper drives
Tool drives: Drill, milling, and cutting tool rotary drives
Material handling: Heavy-duty forklift travel drives, aerial work platform travel systems
Specialty vehicles: Aircraft tractors, port tractors
Expert Maintenance Tips
1. Fluid Cleanliness Management Is the Primary Task
The MKE18 Series operates with micron-level clearances between radial pistons and the cam ring, and between pistons and cylinder bores. Particulate contamination in hydraulic fluid is the leading cause of piston scoring and cam ring wear. Systems must be equipped with filtration rated to ISO 4406 18/16/13 or better. In high-contamination environments such as compactor or mining job sites, consider increasing filtration to ISO 4406 17/15/12 and shortening filter replacement intervals to 500–800 hours.
2. Case Drain Line Configuration Requirements
Case drain from the MKE18 motor must be routed to the reservoir through the highest drain port, with case pressure strictly controlled within specified limits. Excessive case pressure will cause shaft seal failure; insufficient pressure will reduce lubrication and heat rejection effectiveness. The case drain line must terminate below the minimum oil level in the reservoir to maintain positive return flow under all operating conditions. For models equipped with a brake, the brake leakage oil circuit should drain independently and must not share the motor case drain line.
3. Special Considerations for Wheel Drive Installation
The MKE18 Series is specifically designed for wheel drive applications. During installation, verify that the output shaft spline is properly aligned with the wheel hub, and that spline engagement length meets design requirements. Installation misalignment will cause abnormal spline wear and bearing side loading, significantly shortening service life. For wheel drive applications, pay particular attention to the concentricity between the wheel hub and motor flange. Tighten mounting bolts in stages to the specified torque value and re-check torque after 500 operating hours.
4. Pre-Start Case Filling and Air Purging
Before first startup after installation or repair, the motor case must be filled with clean hydraulic fluid through the highest case port until fluid overflows. The MKE18 radial piston architecture creates a complex internal case cavity geometry; starting an un-purged motor can cause dry friction damage between piston ball ends and the cam ring, leading to irreversible premature wear.
5. Low-Speed Smoothness Monitoring and Maintenance
One of the MK18/MKE18 Series’ core advantages is smooth low-speed operation. If crawling or vibration is observed at extremely low speeds, it may indicate increased piston-to-bore clearance, cam ring wear, or flow distribution surface sealing degradation. Record the minimum smooth operating speed under standard conditions quarterly as a trend monitoring baseline; deviation exceeding 15% from the initial value warrants inspection.
6. Restart Procedure After Extended Shutdown
If the motor has been idle for more than three months, manually rotate the output shaft to confirm freedom of movement, and inspect the case oil level and shaft seal for leakage before restarting. Extended shutdown can cause oil film drainage from piston-slipper interfaces, creating a dry-start risk. Before restarting, replenish clean hydraulic fluid through the case fill port and operate at low speed and reduced load for 10–15 minutes before returning to normal duty.
