YUCHAI Mini Excavator Maintenance Guide

Yuchai mini excavators deliver outstanding flexibility and efficiency for global job sites—from urban infrastructure upgrades to rural construction projects worldwide. A science-based, environment-tailored maintenance program is the key to keeping your machine performing at peak levels and extending service life. Proper maintenance will help you:

· Extend equipment life and protect your investment

· Prevent unplanned downtime and costly project delays

· Maintain reliable operation and consistent performance

Yuchai mini excavators are designed for diverse operating environments around the world. Follow this official maintenance guide to unlock the full value of your equipment, no matter where you work.

Maintenance Schedule Overview

Yuchai uses a standardized, hour-based maintenance system with two key intervals:

· 50-hour initial service (after the break-in period for new machines)

· 500-hour regular service (first at 50 hours, then repeated every 500 hours)

Detailed service items and regional environment recommendations are provided below.

50-Hour Initial Maintenance

The break-in period allows components to seat and adapt properly. The 50-hour service is one of the most critical steps in the entire lifecycle of your excavator. Complete all items below when operating hours reach 50.

Engine System

· Replace engine oil and oil filter

· Replace diesel pre-filter and diesel filter

· Inspect coolant level and concentration

· Clean or replace air filter

Hydraulic System

· Check hydraulic oil level

· Inspect hoses and fittings for leaks

· Verify hydraulic oil condition (no emulsification or discoloration)

Undercarriage System

· Clean tracks and remove mud, sand, and debris

· Adjust track sag to ≤30 mm

· Lubricate track pins, idlers, and carrier rollers

· Inspect track shoes and pins for abnormal wear

500-Hour Regular Maintenance

Perform full comprehensive service every 500 operating hours. Inspect, clean, and replace key components in the engine, hydraulic, and undercarriage systems.

Engine System

· Replace engine oil and oil filter

o Warm/high temperature: CJ-4 15W-40

o Cold/winter: 5W-30

· Replace fuel filter; clean fuel tank in high-dust environments

· Replace air filter; add pre-cleaner for dusty/sandy regions

· Inspect cooling system and keep radiator clean

Use the correct diesel fuel grade for your ambient temperature

Hydraulic System

· Replace hydraulic oil and return filter (use HM46 hydraulic oil)

· Inspect all hoses for cracks, aging, or damage

· Maintain hydraulic oil temperature below 65°C during operation

· Check oil condition regularly; replace if abnormal

Undercarriage System

· Deep clean tracks and adjust sag to 25–30 mm

· Lubricate pins, idlers, and carrier rollers (G2-L1 lithium grease recommended)

· Inspect and replace worn track shoes, pins, and rollers

· Check travel motor and reducer for noise or leakage

Common Maintenance Mistakes to Avoid

· Neglecting idle equipment – Check battery and fluids monthly even when not in use

· Using low-quality or incorrect fluids – Always use YUCHAI-specified grades

· Ignoring small items – Skipping minor checks leads to major failures

· Forced cold start in low temperatures – Preheat 3–5 minutes for electric models

· One-size-fits-all maintenance – Adjust intervals for temperature, dust, and workload