Hyundai R140LC-9 Swing Motor 31Q4-11131 AR High Quality Swing Assembly Construction Machinery Aftermarket Parts Manufacturer

This high-precision heavy-duty Swing Motor Assembly has core original part numbers including 31Q4-11131, 31Q4-11130, and 31Q4-11131AR. As a high-end boutique in the aftermarket parts of construction machinery, this assembly is specially designed for Hyundai high-performance hydraulic excavators, perfectly matching 14 ton core flagship models such as R140LC-9 and R145CR-9 (tailless/small turn), serving as the core fluid power source for 360 ° rotation and high-frequency braking of the vehicle body. The product is based on first principles to optimize the shear resistance of high-pressure inclined disc plungers, ensuring absolute certainty of output torque under narrow working conditions. The physical dimensions of the product packaging are approximately 460mm × 360mm × 380mm, with an overall net weight of approximately 58kg. The original factory standard position is precisely aligned.

"Extreme cleaning and torque tightening: Noise reduction and dust removal treatment are required for the unpacking and installation environment. Before installation, the mating surface of the rotary reducer must be thoroughly cleaned to ensure precise and stress free meshing of the output gear shaft. All high-strength fastening bolts must be tightened using torque wrenches, strictly following the factory's specified torque for symmetrical and phased cross tightening to avoid local stress concentration.

Forced oil injection (core avoidance pit): Do not connect the high-pressure oil pipe to the wrong drain pipe (Case Drain). Before starting the engine, it is necessary to fill the top of the swing motor housing with clean hydraulic oil through the bleed/fill port. It is strictly prohibited to start dry grinding, otherwise the internal plunger and distribution plate will undergo irreversible physical erosion within 3 seconds of ignition.

No load micro exhaust transition: After the first ignition, control the upper body to rotate left and right at a small angle and slow speed alternately for 10-15 minutes in a no-load state, thoroughly exhaust the air inside the circuit, and confirm that the thermodynamic state is stable before gradually applying the full working load."