Eaton 2PC25B1115-C 172173-73310 reductor de giro para Yanmar VIO20 VIO20-3 miniexcavadora

1. Product Identification
Component: Hydraulic Swing Motor Device Assembly

Manufacturer Model Number: Eaton 2PC25B1115-C (PC Series Platform)

Yanmar OEM Part Numbers: 172173-73310, 172173-73311 (17217373310, 17217373311)

Machine Compatibility:

Yanmar VIO20 Mini Excavator

Yanmar VIO20-3 Mini Excavator

Condition: Brand New Original / Premium OEM Specification Equivalent

2. Technical Specifications
Type: High-Torque Disc Valve Hydraulic Motor

System Output: Factory-engineered to match the precise displacement, torque parameters, and operational oil flow rates required by Yanmar's VIO (True Zero Tail Swing) 2-ton class excavator series.

Integrated Valve Network: Features an integrated block containing dual crossover cushion relief valves to absorb heavy rotational inertia and eliminate high-pressure spikes during abrupt joystick stops.

Interface Mount: Precision-machined 4-bolt pilot mounting flange with a high-strength spline shaft engineered to mesh directly into the factory upper structure slew gearbox.

3. Critical Installation Requirements
Motor Case Priming (Mandatory)
Before starting the engine or cycling the hydraulics for the first time, you must manually pre-fill the swing motor casing with clean, fresh hydraulic oil through its highest available case drain port. Running an Eaton disc-valve motor dry—even for a few moments—will cause immediate frictional scoring on the internal wear plates and lead to total internal pressure bypass.

Verify Case Drain Line Clearance
Thoroughly inspect the low-pressure case drain hose leading from the motor back to the hydraulic oil reservoir. Ensure it is completely free of sharp bends, kinks, or inner wall collapses. Any flow restriction in this return line creates excessive housing backpressure, which will instantly blow out the motor's main shaft seal.

Gear Pinion & Slew Ring Lubrication
Ensure that the mounting pocket on the Yanmar chassis is clear of dirt, rust, and old debris. Apply a generous, uniform coating of premium heavy-duty lithium gear grease to the motor’s output spline shaft pinion and the matching teeth of the upper structure slew ring gear during installation.

Fluid & Circuit Decontamination
If the previous swing motor failed due to a severe mechanical breakdown, you must drain the hydraulic reservoir, flush the main control valve's swing spool circuit hoses, and clear out the oil cooler lines. Residual metal particles left behind in the old fluid will rapidly wear down and destroy the newly installed motor.

4. Frequently Asked Questions (FAQ)
Q: Are part numbers 172173-73310 and 172173-73311 interchangeable?
A: Yes. The part number ending in -73311 is a direct factory engineering supersession and product update of the older -73310 designation. Both reference the exact same Eaton 2PC25B1115-C motor framework, sharing matching physical dimensions and performance ratings.

Q: My Yanmar VIO20-3 cabin drifts slowly to the side when I work on a slope or try to stop rotating. Will this fix it?
A: Yes. Over-swinging, drifting when the joystick is in neutral, or a structural shudder during a stop indicates that the integrated cushion relief valves or internal wear seals inside the motor housing have degraded. Replacing the complete device restores exact stopping and hydraulic braking holding power.

Q: Does the swing motor arrive fully assembled and ready to bolt on?
A: Yes. Our premium assemblies are shipped complete with the factory-calibrated valve blocks and internal dynamic groups pre-tested for immediate, plug-and-play installation.

5. Shipping & Logistics
Packaging: Thoroughly preserved with anti-corrosion storage oil, sealed with heavy-duty plastic port plugs to prevent dirt ingress, and packaged securely inside an export-safe protective box.

Transit Time: Global express air freight via DHL/FedEx/UPS typically delivers within 3 to 7 business days directly to your workshop or job site.