157-0930 Final Drive Track Motors Assembly Fit Mag85 CAT312

This high-precision heavy-duty travel device assembly (integrating high-pressure travel motor and planetary gearbox) has core original part numbers and cross index numbers of 142-6825 and 157-0930. The core adopts the classic MAG-85VP (Mag85) high-pressure dual speed plunger travel motor from a well-known factory. This Final Drive assembly is specially designed for Caterpillar's classic small and medium-sized hydraulic excavators, perfectly matching the 12 ton gold core models such as CAT 312, 312B, 312C, and E312 series. The product is optimized based on first principles for high torque multi-stage planetary transmission, ensuring absolute certainty of propulsion torque in harsh muddy conditions. The physical dimensions of the product packaging are approximately 540mm × 420mm × 440mm, with an overall net weight of approximately 115kg. The original factory standard position is precisely aligned.

"Extreme cleaning and torque tightening: Before lifting and docking, the installation surface of the frame base and drive wheel flange must be absolutely flat and free of any rust or foreign objects. 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 abnormal local stress on one side.

Motor forced oil filling (core avoidance pit): When connecting hydraulic pipelines, they must be absolutely aligned and do not connect the wrong drain pipe (Case Drain). Before starting the engine, clean hydraulic oil must be filled from the air release/oil injection port on the top of the walking motor housing. Dry grinding is strictly prohibited for starting, otherwise the internal plunger rotating components will undergo physical erosion within 3 seconds of ignition.

Idle micro exhaust transition: Use a working device to suspend the entire machine's single-sided track support, control the walking mechanism to run slowly and alternately in front and back micro motion for 10-15 minutes, thoroughly exhaust the circuit air, and closely monitor the gear meshing sound. Only after confirming the thermodynamic state is stable can the working load be applied on the ground."