Редуктор хода Hitachi HMGF35 9120000 9131678 для среднего экскаватора Hitachi EX200-3

EX200‑3 Final Drive for Excavator spare parts 9120000 9131678 HMGF35 Aftermarket

Product Overview

Every time an EX200‑3 crawls up a ramp or pushes across soft ground, the HMGF35 drive under that track is taking the load. It is the hydraulic motor and planetary reducer that turns pump flow into the slow, powerful rotation at the sprocket — a component that works quietly for years, then announces its wear all at once. On these older Hitachis, the first sign is usually that the two tracks no longer match: one lags, the machine pulls slightly off line, and the drive housing runs warmer than its opposite after a run. By the time a track hesitates under load, the piston group and reduction gears are already scoring against each other. The references 9120000 and 9131678 cover this drive across the EX200‑3 build run, and this aftermarket unit reproduces that original motor‑and‑reducer pairing as one sealed, tested assembly — so the worn drive comes off and the new one goes straight on, without sourcing separate parts.

Core Advantages

1. A piston group that holds pressure under load
The motor's piston, cylinder block and valve plate are finished to tight clearances, so hydraulic pressure does not leak away inside the unit. Both tracks then pull in step — no drift, no slow side, no hesitation the moment the bucket loads up.

2. Gears built for a 20‑ton machine's daily reversing
The planetary gear set is hardened and precision‑cut with controlled backlash. Smooth, even meshing spreads the drive torque across the teeth rather than hammering onto a few, which is how gears last on a machine that reverses all shift long.

3. Sealed against the dust and water of old‑site work
These excavators spend long hours in quarry dust, mud and standing water. Fitted output‑shaft and housing seals keep grit out of the motor and reducer — the protection that decides whether the drive survives or fails early.

4. Arrives as one tested unit, ready to fit
Motor and gearbox come pre‑assembled and bench‑checked, so the fitter removes the old drive and bolts on the new one without having to source or mate separate components. On a legacy machine where workshop time is tight, that matters.

5. Aftermarket value for a machine past its warranty years
An original Hitachi drive exchange is hard to justify on an older EX200‑3. This aftermarket unit restores track mobility at a practical cost, with sample and batch supply for workshops keeping these machines running.

Manufacturing & Quality Control

Production is traceable from incoming steel through machining, case hardening and clean assembly. Before packing, every drive runs on a test bench to check output torque, internal leakage and operating noise; anything outside the acceptance limits is rejected. Completed units are preservation‑coated, sealed against moisture and shock‑crated for sea and overland freight.

Frequently Asked Questions

Q1: How do I know which reference fits my machine?
A: Check the tag on your existing drive against 9120000 or 9131678, and send the machine serial number. Build variants can occur, so we confirm before dispatch.

Q2: Does this come ready to install?
A: Yes — the motor and reducer are supplied as one complete, tested assembly with seals fitted. After bolting it on, bleed the travel circuit and check oil level before use.

Q3: What faults suggest the drive is wearing out?
A: Mismatched track speeds, pulling to one side, a warm or noisy track motor and hesitation under load. Catch it early and the damage stays inside the drive; leave it and contamination spreads.

Q4: What does the warranty cover?
A: Material and workmanship defects are covered. Damage from contaminated oil, debris entering the motor, track obstruction, overload or incorrect fitting is excluded — follow the Hitachi service manual for installation.