Fault Phenomenon: Sumitomo SC1500 during high-load operation, the water temperature gauge enters the red zone, engine alarms.

Troubleshooting Process:
– Checked coolant level: level normal.
– Checked radiator surface: severely clogged with dust and cotton debris.
– Checked fan belt: tension normal.
– After cleaning and flushing the radiator, water temperature returned to normal.

Root Cause: External blockage of the radiator caused reduced cooling efficiency.

Required Parts: Coolant (for top-up), radiator cleaner.