6 Key Points for Daily Maintenance of Hydraulic Systems

  Hydraulic systems are widely used in hydraulic power stations, construction machinery and automated equipment. Oil leakage, insufficient pressure, abnormal noise and jerky movements are rarely sudden failures; most are caused by long‑term poor maintenance. Standard daily maintenance can greatly reduce breakdowns, cut repair costs and prolong the service life of hydraulic equipment. Below are six core points for hydraulic system daily maintenance.

1. Check Hydraulic Oil Quality and Oil Level

    Hydraulic oil is the blood of the hydraulic system. Check the oil level in the oil tank every day. Keep the oil level within the standard range. Low oil level causes air intake, bubbles, jitter and unstable pressure. Excessively high oil level leads to poor heat dissipation and oil overflow.Regularly observe oil color and clarity. Dark, turbid, foamy or milky emulsified oil indicates deterioration; filter or replace oil promptly. Always use the hydraulic oil grade specified for your machine. Do not mix different oil types arbitrarily.

2. Monitor and Control Oil Temperature

    The ideal operating oil temperature ranges from 30‑55℃. Temperatures above 60℃ accelerate oil oxidation and seal aging, resulting in internal leakage and pressure loss. Too‑low temperature increases oil viscosity and makes equipment move sluggishly.During routine inspection, verify radiators and cooling fans work normally, clean dust and grease from radiator surfaces. Avoid prolonged full‑load continuous operation. Stop the machine for troubleshooting if oil temperature rises abnormally; do not run faulty equipment.

3. Inspect Seals and Pipelines for Leakage

    Oil leakage is one of the most common hydraulic problems, and minor seepage is often ignored. Inspect oil tubes, joints, valve blocks, cylinders and pump bodies for oil seepage or dripping.Tighten loose connections and replace worn or damaged seals immediately. Replace bulged or cracked pipelines in time. Small leaks will worsen without treatment; contaminants may enter the system and wear spools and pump cores.

4. Inspect and Replace Filters Regularly

    Filters remove contaminants. Clogged filters lead to insufficient oil supply and loud noise. Check suction and return‑line filters according to maintenance schedules.Replace blocked or damaged filters in time. Never run the hydraulic system with filters removed. Replace filters together with hydraulic oil to prevent residual dirt from contaminating new oil.

5. Inspect Operating Conditions: Pressure and Abnormal Noise

   Observe equipment status while running: check whether pressure stays stable and listen for unusual noise or vibration.Abnormal noise usually points to air ingestion, clogged filters or pump wear. Pressure fluctuation or pressure drop requires checking valves, check valves, relief valves and cylinder internal leakage.Keep operation records and compare against normal working parameters. Detect early warning signs to prevent minor faults from turning into major overhauls.

6. Dust‑proof & Waterproof, Keep Hydraulic System Clean

    Dust, moisture and impurities are hidden hazards for hydraulics. Keep breather caps and air valves intact to stop dust and rainwater entering the tank. Take protective measures when disassembling pipes and valves to prevent external contaminants from entering oil circuits.Keep the area around hydraulic power stations tidy and clean surface grease regularly. Thoroughly clean parts before assembly during repair work, to avoid debris causing spool sticking and pump abrasion.

Conclusion

More than 70% of hydraulic system failures stem from inadequate maintenance. Follow the six daily‑maintenance points covering oil condition, temperature, seals, filters, operating performance and cleanliness. You can effectively prevent typical faults such as pressure loss, oil leakage, valve sticking and pump damage, reduce unplanned downtime and maximize hydraulic‑equipment performance.