I. Causes of High Water Temperature

1. Thermostat Malfunction: A stuck thermostat restricts coolant flow to the radiator, forcing the system into a small circulation loop.

2. Cooling System Blockage: Dirty water tanks or clogged radiator cores disrupt coolant flow. Use an infrared thermometer to detect temperature differences—significant lower temperatures at the radiator’s lower section indicate blockages 

3. Insufficient Fan Speed: Hydraulic-driven fans may underperform due to clutch failures or overflow device issues.

4. Airflow Recirculation: Damaged radiator seals create turbulent airflow, trapping hot air around the radiator.

5. Sensor Errors: Malfunctioning temperature sensors or faulty wiring can trigger false alarms.

II. Causes of High Oil Temperature

1. Return Oil Check Valve Sticking: A blocked valve disrupts large circulation, causing oil temperature spikes.

2. Cooling Path Restrictions: Similar to water systems, oil cooler blockages or poorly designed return lines reduce heat dissipation.

3. Oil Quality Degradation: Prolonged high temperatures accelerate oxidation, reducing lubrication efficiency.

III. Priority: Lower Oil Temperature First

When both oil and water temperatures exceed 90°C, prioritize reducing oil temperature to protect critical components:

1. Mitigate Bearing Damage: At 110°C, oil film temperatures in crankshaft bearings reach 150°C, risking copper-lead alloy melting and catastrophic failure 

2. Indirect Water Cooling: Reducing oil temperature indirectly slows water temperature rise by lowering engine load and friction heat.

3. Stabilize Oil Pressure: High oil temperatures reduce viscosity, weakening lubrication films and main oil gallery pressure. Water temperature regulation relies on resolving oil temperature issues first.

IV. Emergency Response Protocol

1. Immediate Actions:

• Cease high-load operations and activate auxiliary cooling systems.

• Inspect fan operation and coolant levels (avoid opening the radiator cap under pressure).

2. Systematic Checks:

• Verify thermostat functionality and radiator cleanliness.

• Test oil cooler integrity and check for oil leaks.

3. Preventive Maintenance:

• Regularly replace coolant and clean cooling systems.

• Monitor sensor accuracy and replace aging seals.

V. Key Takeaways

• Cooling System Design: Construction machinery uses hydraulic-driven fans and overflow valves for adaptive cooling.

• Material Risks: Excessive heat compromises copper-lead bearings, leading to irreversible damage.

• Operational Discipline: Adhere to "reduce load, lower RPM" protocols during overheating to balance heat generation and dissipation.

Regular maintenance and prompt troubleshooting can reduce overheating incidents by 65%, ensuring machinery longevity and performance.