Product Overview
The M5BF and M5AF Series hydraulic motors are Parker Denison’s classic fixed-displacement vane motors, optimized for fan drive applications. The M5BF Series spans 6 displacement sizes — M5BF012, M5BF018, M5BF023, M5BF028, M5BF036, and M5BF045 — with displacements ranging from 12.0 to 45.0 cm³/rev. The M5AF Series spans 7 displacement sizes from M5AF006 to M5AF025, with displacements ranging from 6.3 to 25.0 cm³/rev. Both series feature a 12-vane rotor and patented cartridge design, achieving extremely low noise levels with low torque ripple (typically ±1.5%) for smooth operation at any speed.
The M5BF/M5AF motors feature integrated valve assemblies that transform the motor into a complete hydraulic cooling unit, saving installation time and cost for OEM customers and end users. The series employs heavy-duty double ball bearings that allow the fan blade to be mounted directly on the motor shaft, eliminating the need for external bearing support and significantly simplifying fan drive system layout.
This product is a drop-in interchange replacement for genuine Parker Denison M5BF/M5AF Series hydraulic motors. Mounting flange (2-bolt Ø135mm or 4-bolt mounting), shaft extension (ISO G32N cylindrical keyed or taper shaft), SAE 3/4″ main ports, and M18×1.5 drain port are dimensionally identical to OEM specifications, enabling direct replacement without hydraulic circuit or mounting modification. Every motor is subjected to 100% simulated actual-load testing before shipment, ensuring volumetric efficiency, output torque, and sealing performance meet OEM technical standards.
OEM Part Number Coverage:
M5BF Series: M5BF 023 WN04 B1M 00000, M5BF 028 1N02 B1M3 M534168, M5BF-045-1N03, M5BF 045 1R01 B1B3 21 M534885 and other standard configuration codes
M5AF Series: M5AF 006/010/012/016/018/023/025 full displacement coverage
Cross-reference numbers: 054-35493-0, 054-38496-0, 024-94682-0, 024-94705-0, etc.
Technical Specifications
M5BF Series Displacement & Performance:
M5BF012: Displacement 12.0 cm³/rev; Max continuous pressure 290 bar; Max intermittent pressure 320 bar; Max continuous speed 4000 rpm; Max intermittent speed 6000 rpm; Max output torque 50.6 Nm; Max output power 10.6 kW; Weight approx. 18.5 kg
M5BF018: Displacement 18.0 cm³/rev; Max continuous pressure 290 bar; Max intermittent pressure 320 bar; Max continuous speed 4000 rpm; Max intermittent speed 6000 rpm; Max output torque 81.2 Nm; Max output power 17.0 kW; Weight approx. 18.5 kg
M5BF023: Displacement 23.0 cm³/rev; Max continuous pressure 290 bar; Max intermittent pressure 320 bar; Max continuous speed 4000 rpm; Max intermittent speed 4000 rpm; Max output torque 117.1 Nm; Max output power 24.5 kW; Weight approx. 18.5 kg
M5BF028: Displacement 28.0 cm³/rev; Max continuous pressure 290 bar; Max intermittent pressure 320 bar; Max continuous speed 2500 rpm; Max intermittent speed 4000 rpm; Max output torque 132.1 Nm; Max output power 27.7 kW; Weight approx. 18.5 kg
M5BF036: Displacement 36.0 cm³/rev; Max continuous pressure 290 bar; Max intermittent pressure 320 bar; Max continuous speed 2500 rpm; Max intermittent speed 4000 rpm; Max output torque 172.8 Nm; Max output power 36.2 kW; Weight approx. 18.8 kg
M5BF045: Displacement 45.0 cm³/rev; Max continuous pressure 200 bar; Max intermittent pressure 280 bar; Max continuous speed 2500 rpm; Max intermittent speed 3000 rpm; Max output torque 172.8 Nm (calculated); Max output power —; Weight approx. 15.8 kg
M5AF Series Displacement & Performance:
M5AF006: Displacement 6.3 cm³/rev; Max continuous pressure 300 bar; Max intermittent pressure 300 bar; Max continuous speed 4000 rpm; Max intermittent speed 5000 rpm; Max output torque 26.1 Nm; Max output power 5.5 kW; Weight approx. 15.0 kg
M5AF010: Displacement 10.0 cm³/rev; Max continuous pressure 300 bar; Max intermittent pressure 300 bar; Max continuous speed 4000 rpm; Max intermittent speed 5000 rpm; Max output torque 43.7 Nm; Max output power 9.2 kW; Weight approx. 15.0 kg
M5AF012: Displacement 12.5 cm³/rev; Max continuous pressure 300 bar; Max intermittent pressure 300 bar; Max continuous speed 4000 rpm; Max intermittent speed 3800 rpm; Max output torque 55.7 Nm; Max output power 11.7 kW; Weight approx. 15.0 kg
M5AF016: Displacement 16.0 cm³/rev; Max continuous pressure 300 bar; Max intermittent pressure 300 bar; Max continuous speed 4000 rpm; Max intermittent speed 3800 rpm; Max output torque 71.4 Nm; Max output power 15.2 kW; Weight approx. 15.0 kg
M5AF018: Displacement 18.0 cm³/rev; Max continuous pressure 300 bar; Max intermittent pressure 300 bar; Max continuous speed 4000 rpm; Max intermittent speed 3300 rpm; Max output torque 81.2 Nm; Max output power 17.0 kW; Weight approx. 15.5 kg
M5AF023: Displacement 23.0 cm³/rev; Max continuous pressure 280 bar; Max intermittent pressure 280 bar; Max continuous speed 3000 rpm; Max intermittent speed 3000 rpm; Max output torque —; Max output power —; Weight approx. 15.0 kg
M5AF025: Displacement 25.0 cm³/rev; Max continuous pressure 280 bar; Max intermittent pressure 280 bar; Max continuous speed 2500 rpm; Max intermittent speed 3000 rpm; Max output torque —; Max output power —; Weight approx. 15.0 kg
Model Code Breakdown (Example: M5BF 023 WN04 B1M 00000):
M5BF: Product series (M5B Series fan drive motor, externally drained)
023: Displacement code (23.0 cm³/rev)
WN04: Mounting/porting configuration code
B1M: Shaft & rotation code (B1 = clockwise, B2 = counter-clockwise, N = bi-directional)
00000: Standard option code
Configuration Parameters:
Control type: Fixed displacement, vane type
Motor type: M5BF externally drained; M5AF externally drained
Rotation: M5BF/M5AF externally drained available in bi-directional, clockwise, or counter-clockwise configurations
Mounting flange: Special mounting (2-bolt Ø135mm) or 4-bolt
Shaft options: ISO G32N cylindrical keyed or taper shaft (direct fan blade mounting)
Main ports: SAE 3/4″ 3000 PSI, metric thread
Drain port: M18×1.5 metric thread
Seal material: Buna-N (NBR) standard
Bearings: Heavy-duty double ball bearings, direct fan load mounting capable
Integrated valves: Cross-port check valve for smooth dynamic braking and cavitation prevention (select models)
Overall efficiency: Up to 90% at 300 bar (M5A series) and 320 bar (M5B series)
Key Technical Advantages
1. Patented 12-Vane Cartridge Design with Ultra-Low Noise
The M5BF/M5AF Series employs a 12-vane rotor and patented cartridge design, optimizing vane count and cam ring profile to achieve extremely low operating noise at any speed. Combined with low internal dead volume, the design delivers a typical torque ripple of only ±1.5% across the full speed range, significantly outperforming competitive designs — particularly suitable for noise-sensitive construction machinery fan drive applications.
2. Integrated Valve Assembly — Complete Hydraulic Cooling Unit
The M5BF/M5AF motors feature integrated valve assemblies including anti-cavitation check valves, anti-starve valves, and reversing valves, transforming the motor into a complete hydraulic cooling unit. This design saves external piping and valve components, reduces installation costs, and improves system reliability by reducing leak points. The cross-port check valve in uni-directional models enables smooth dynamic braking without risk of motor cavitation.
3. Heavy-Duty Double Ball Bearings with Direct Fan Mounting
The M5BF/M5AF Series features heavy-duty double ball bearings at the output end, capable of withstanding the axial and radial loads generated by the fan. This allows the fan blade to be mounted directly on the motor’s taper or cylindrical keyed shaft, eliminating the need for additional external bearing support. A sealed barrier behind the motor shaft seal protects against external debris ingress, extending seal service life.
4. High Volumetric Efficiency and Long Service Life
The vanes, rotor, and cam ring of the M5BF/M5AF Series are pressure-balanced to increase life over the full speed range. Double-lip vane design reduces sensitivity to fluid pollution. Overall motor efficiency reaches up to 90% at 300–320 bar operating pressure. Vane motors begin life with high volumetric efficiency and maintain that efficiency throughout their operating life.
Application Areas
Construction Machinery Fan Drive (Core Application): Excavator hydraulic fan drive (ZX470, E330LC, E360LC, etc.), loader fan drive, crane hydraulic cooling systems
Road Machinery: Road roller fan drive, paver cooling fan drive
Agricultural Machinery: Combine harvester fan drive, tractor cooling system
Industrial Equipment: Hydraulic cooling units, compressor drive, generator drive
Other Applications: Mixer drive, shredder drive, hydraulic hybrid systems
Expert Maintenance Tips
Pre-Installation Preparation:
Clean all ports and mounting flanges with lint-free wipes or clean compressed air before installation. Verify O-ring integrity. The M5BF/M5AF mounting flange (2-bolt Ø135mm) and shaft dimensions are identical to Parker Denison OEM specifications, allowing direct use of OEM mounting bolts. Torque mounting bolts in a diagonal sequence over 2–3 passes. After installation, manually rotate the output shaft to confirm free and smooth rotation without binding. Note that M5AF/M5BF are externally drained configurations — ensure the drain line is correctly connected.
Drain Port Management:
The M5AF/M5BF are externally drained motors — the drain port (M18×1.5) must be connected to a drain line routed separately back to the reservoir with the end submerged below the oil level. Drain line back pressure must not exceed 2 bar; excessive back pressure will damage the shaft seal. If the M5AF1/M5BF1 internally drained model is used, no external drain line is required.
Hydraulic Fluid Management:
Use anti-wear hydraulic oil with ISO VG 46 or ISO VG 68 viscosity grade. The M5B Series is designed to maintain sustained high-pressure and high-speed performance even under low fluid lubricity conditions, but fluid cleanliness should still be maintained at ISO 18/16/13 or NAS Class 8 minimum. Operating temperature should not exceed 80°C continuous; short-term peak up to 95°C is acceptable. Replace hydraulic fluid after the first 50 operating hours.
Rotation Direction Verification:
M5BF/M5AF externally drained models are available in bi-directional, clockwise (A1/B1), and counter-clockwise (A2/B2) rotation configurations. Verify motor rotation direction matches system requirements before installation. Uni-directional models feature an internal cross-port check valve and must not be operated in reverse.
Periodic Inspection:
Check volumetric efficiency every 500 operating hours or quarterly. Test method: lock the output shaft at rated pressure and measure leakage flow. If leakage exceeds 10% of rated flow, internal wear has entered an accelerated phase — schedule service or replacement. Also inspect shaft seals for seepage and double ball bearings for abnormal noise or vibration. The rotating group (rotor, vanes, cam ring) is interchangeable — rotating groups may be easily replaced to renew the motor or change the displacement to suit altered requirements for speed or torque.
