M5BS 018 Hydraulic Motor | Parker Denison Fan Drive Vane

Product Overview

The M5 Series hydraulic motor is Parker Denison’s classic high-performance fixed-displacement vane motor, specifically designed for severe duty applications. The series encompasses multiple sub-families including M5A, M5AF, M5B, M5BS, and M5BF, with displacements ranging from 6.3 to 45.0 cm³/rev. Featuring a patented 12-vane cartridge design, the M5 Series delivers extremely low noise levels, low torque ripple (typically ±1.5%), and high starting torque efficiency. The M5 Series maintains long life at operating pressures up to 320 bar and speeds up to 6000 rpm, even with low-lubricity hydraulic fluids.

The M5BS 018 (OEM part number 024-94709-002) is an 18 cc displacement model in the M5B Series, with a geometric displacement of 18.0 cm³/rev, maximum continuous pressure of 290 bar, maximum intermittent pressure of 320 bar, maximum speed of 4000 rpm, and maximum output torque of 81.2 Nm. The M5BS and M5B are bi-rotational motors with external drainage, featuring cylindrical keyed or splined shafts conforming to SAE J744, J498, or ISO 3019-2 standards.

The M5 Series 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 bearings that allow the fan blade to be mounted directly on the motor shaft, eliminating the need for external bearing support. Parker recommends an excluder shaft seal on fan motors to protect the shaft seal from contamination.

This product is a drop-in interchange replacement for genuine Parker Denison M5BS 018 (024-94709-002) hydraulic motors. Mounting flange (SAE B 2/4-bolt), shaft extension (SAE B keyed or 13-tooth splined), 3/4″ SAE 3000 main ports, and case drain port are dimensionally identical to OEM specifications, enabling direct replacement without hydraulic circuit or mounting modification. The rotating group (cam ring, rotor, vanes, and springs) is interchangeable — rotating groups may be easily replaced to renew the motor or change the displacement to suit altered requirements for speed or torque. 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:

• M5BS 018: 024-94709-002 (3N00 B102), 054-34655-003 (3N00 B1M3), 024-94708-001 (1N00 B102)

• M5B Series: M5B 012/018/028/036/045 full displacement coverage

• M5AF Series: M5AF 006/010/012/016/018/023/025 full displacement coverage

• M5BF Series: M5BF 012/018/023/028/036/045 full displacement coverage

• Cross-reference: 054-45849-5, 054-49403-0, 054-46784-0, 024-94709-0

Technical Specifications 

M5BS 018 (024-94709-002) Core Specifications:

• Model Code: M5BS 018

• OEM Part Number: 024-94709-002 (3N00 B102) / 054-34655-003 (3N00 B1M3)

• Series: Parker Denison M5B Series (High Performance Vane Motor)

• Product Type: Fixed displacement vane motor, bi-rotational, externally drained

• Geometric displacement: 18.0 cm³/rev (1.10 in³/rev)

• Max continuous pressure: 290 bar (4200 PSI)

• Max intermittent pressure: 320 bar (4600 PSI)

• Max continuous speed: 4000 rpm

• Max intermittent speed: 6000 rpm (low loaded conditions)

• Max output torque: 81.2 Nm (@100 rpm)

• Max output power: 17.0 kW (@100 rpm)

• Theoretical torque: 0.286 Nm/bar

• Overall efficiency: Up to 90% at 320 bar

• Torque ripple: Typically ±1.5%

• Minimum stable speed: 10 rpm

• Control type: Fixed displacement, 12-vane cartridge design

• Mounting flange: SAE B 2/4-bolt

• Shaft type: SAE B keyed or SAE B 13-tooth splined

• Main ports: 3/4″ SAE 3000, metric thread or UNC thread

• Drain port: SAE 6 – 9/16″ UNF / M12×1.5 / 1/4″ BSPP / M18×1.5

• Rotation: Bi-directional (M5BS externally drained)

• Seal material: Buna-N (NBR) standard, Viton optional

• Bearings: Heavy-duty bearings, direct fan mounting capable

• Integrated valves: Optional anti-cavitation check valve, anti-starve valve, reversing valve

• Weight: Approx. 18.5 kg

M5B Series Full Range Specifications:

• M5B 012: Displacement 12.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 4000 rpm; Max output torque 50.6 Nm; Max output power 10.6 kW; Weight approx. 18.5 kg

• M5B 018: Displacement 18.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 4000 rpm; Max output torque 81.2 Nm; Max output power 17.0 kW; Weight approx. 18.5 kg

• M5B 028: Displacement 28.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 2500 rpm; Max output torque 132.1 Nm; Max output power 27.7 kW; Weight approx. 18.5 kg

• M5B 036: Displacement 36.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 2500 rpm; Max output torque 172.8 Nm; Max output power 36.2 kW; Weight approx. 18.8 kg

• M5B 045: Displacement 45.0 cm³/rev; Max continuous pressure 200 bar; Max continuous speed 2500 rpm; Weight approx. 15.8 kg

M5AF Series Displacement & Performance:

• M5AF 006: Displacement 6.3 cm³/rev; Max continuous pressure 300 bar; Max continuous speed 4000 rpm; Max output torque 26.1 Nm; Max output power 5.5 kW

• M5AF 010: Displacement 10.0 cm³/rev; Max continuous pressure 300 bar; Max continuous speed 4000 rpm; Max output torque 43.7 Nm; Max output power 9.2 kW

• M5AF 012: Displacement 12.5 cm³/rev; Max continuous pressure 300 bar; Max continuous speed 4000 rpm; Max output torque 55.7 Nm; Max output power 11.7 kW

• M5AF 016: Displacement 16.0 cm³/rev; Max continuous pressure 300 bar; Max continuous speed 4000 rpm; Max output torque 71.4 Nm; Max output power 15.2 kW

• M5AF 018: Displacement 18.0 cm³/rev; Max continuous pressure 300 bar; Max continuous speed 4000 rpm; Max output torque 81.2 Nm; Max output power 17.0 kW

• M5AF 023: Displacement 23.0 cm³/rev; Max continuous pressure 280 bar; Max continuous speed 3000 rpm

• M5AF 025: Displacement 25.0 cm³/rev; Max continuous pressure 280 bar; Max continuous speed 2500 rpm

M5BF Series Displacement & Performance:

• M5BF 012: Displacement 12.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 4000 rpm; Max output torque 50.6 Nm; Max output power 10.6 kW

• M5BF 018: Displacement 18.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 4000 rpm; Max output torque 81.2 Nm; Max output power 17.0 kW

• M5BF 023: Displacement 23.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 3000 rpm; Max output torque 117.1 Nm; Max output power 24.5 kW

• M5BF 028: Displacement 28.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 3000 rpm; Max output torque 132.1 Nm; Max output power 27.7 kW

• M5BF 036: Displacement 36.0 cm³/rev; Max continuous pressure 290 bar; Max continuous speed 3000 rpm; Max output torque 172.8 Nm; Max output power 36.2 kW

• M5BF 045: Displacement 45.0 cm³/rev; Max continuous pressure 260 bar; Max continuous speed 2500 rpm

Key Technical Advantages

1. Patented 12-Vane Cartridge Design with Ultra-Low Noise
The M5 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. The 12-vane configuration further optimizes flow ripple characteristics compared to conventional 10-vane designs, significantly reducing pressure pulsation and operating noise.

2. Integrated Valve Assembly — Complete Hydraulic Cooling Unit
The M5 Series 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 Bearing System with Direct Fan Mounting
The M5BS 018 features heavy-duty 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 keyed or splined shaft, eliminating the need for additional external bearing support. A sealed barrier behind the motor shaft seal protects against external debris ingress. Parker recommends an excluder shaft seal on fan motors to further protect the shaft seal from contamination and extend seal service life.

4. Interchangeable Rotating Groups with Wide Displacement Adaptability
The M5 Series features precision manufacturing that allows any component to be interchangeable. Users can easily renew the motor or change the displacement to suit altered requirements for speed or torque by replacing the cartridge, significantly reducing spare parts inventory costs and maintenance complexity. The series is also compatible with Danfoss/White 500/530 Series and Eaton Char-Lynn equivalent models, further expanding interchangeability. The M5B Series offers 5 displacement sizes from 012 to 045, allowing users to select the optimal model for their specific operating conditions.

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 M5BS 018 uses an SAE B 2/4-bolt flange — confirm the flange specification matches the system before installation. 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 M5BS is an externally drained configuration — ensure the drain line is correctly connected.

Drain Port Management:
The M5BS 018 is an externally drained motor — the drain port 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. The case drain port size is SAE 6 – 9/16″ UNF or M12×1.5 metric thread. If an 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 M5 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. Internal parts are lubricated by the operating fluid itself; therefore, preventive maintenance is limited to keeping the fluid clean and maintaining an acceptable viscosity range. System filters should be replaced frequently.

Rotation Direction Verification:
The M5BS is a bi-rotational motor. Verify motor rotation direction matches system requirements before installation. Rotation is viewed from the shaft end: R=CW stands for clockwise, L=CCW for counter-clockwise, N for bi-rotational. 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 heavy-duty bearings for abnormal noise or vibration. Check frequently that all fittings and bolts are tight at correct torque. When performance restoration or displacement change is required, the rotating group (cam ring, rotor, vanes, and springs) can be replaced to renew the motor.