مخفض آلية الدوران Eaton 2P2044773 2P200486 2P204065 1000358872 لـ حفارة صغيرة Caterpillar 301.4C 301.7D

1. Product Identification
Component: Hydraulic Swing Motor Device Assembly

Manufacturer Model Numbers: Eaton 2P2044773, 2P200486, 2P204065

Caterpillar OEM Part Numbers: 1000358872, 399-3002, 399-2941, 379-2897 (3993002, 3992941, 3792897)

Machine Compatibility:

Caterpillar (CAT) 301.4C Mini Excavator

Caterpillar (CAT) 301.7D Mini Excavator

Condition: Brand New Original / Premium OEM Specification Equivalent

2. Technical Specifications
Type: Compact Geroler / Disc Valve Hydraulic Motor (Eaton Design)

System Output: Configured to deliver the exact displacement, torque curve, and flow thresholds demanded by the CAT 1.4 to 1.7-ton mini excavator swing loops.

Integrated Valve Network: Features factory-integrated crossover relief and cushion valves designed to eliminate hydraulic spikes and control cabin rotation inertia.

Interface Mount: Precision mounting flange with a high-strength spline shaft engineered to bolt directly into the mini excavator's upper structure rotation gearbox.

3. Critical Installation Requirements
Motor Case Priming (Mandatory)
Before starting the engine or cycling any joystick functions, you must manually fill the swing motor casing with clean, fresh hydraulic oil through its highest available case drain port. Running a hydraulic motor dry for even a few seconds will permanently score internal wear surfaces and cause immediate internal bypass.

Verify Case Drain Line Clearance
Thoroughly inspect the case drain line back to the hydraulic oil tank. Ensure there are no kinks, sharp bends, or internal structural collapses. Any unexpected backpressure in this low-pressure line will immediately blow out the main shaft seal.

Gear Pinion & Slew Ring Lubrication
Thoroughly clean the mounting pocket on the excavator frame. Apply a thick, uniform layer of premium heavy-duty lithium gear grease to the motor's output shaft pinion and the matching upper structure slew ring gear teeth during assembly.

System Fluid Decontamination
If the previous motor failed due to an internal mechanical breakdown, you must drain the hydraulic reservoir, flush the control valve's swing spool lines, and clear the oil cooler circuit. Residual steel or bronze particles will rapidly score and destroy your new unit.

4. Frequently Asked Questions (FAQ)
Q: Are all these part numbers (399-3002, 399-2941, 379-2897) interchangeable?
A: Yes. These numbers represent standard Caterpillar part number successions, engineering updates, and factory transitions for the 301.4C and 301.7D model lines. They all tie back to the same Eaton 2P series base frame sizes, offering identical physical mounts and performance specs.

Q: My CAT mini excavator drifts to the side when I dig or park on a slight incline. Will this fix it?
A: Yes. Over-swinging, sluggish stopping, or drifting when joysticks are in neutral indicates that the integrated cushion relief valves or internal friction plates within the motor housing have worn down. A complete replacement unit restores factory-spec holding and stopping 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 debris entry, 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.