Faults and Inspection of Diesel Generator Cooling System

 
In diesel generator sets, the cooling system plays a crucial role in maintaining the engine within the appropriate temperature range under various operating conditions, ensuring its normal operation. However, the cooling system is also prone to malfunctions. Here is a detailed overview of the common faults in the cooling system of diesel generator sets and the corresponding inspection methods:
 

1. Insufficient Circulating Water Volume

 
One of the common reasons for diesel generator overheating is insufficient circulating water volume. When there is not enough cooling water, the engine cannot be adequately cooled, which may lead to deformation of mechanical components and reduction of clearance between parts, or even result in component cracks. Additionally, high oil temperature can affect lubrication efficiency, increasing component wear. Therefore, it is essential to regularly check the coolant level. Before starting the generator set, carefully inspect whether the coolant meets the requirements. During operation, pay attention to any leakage of coolant, especially around the radiator, water pump, cylinder block, heater core, hoses, and drain valve.
 

2. Low Water Pump Supply Efficiency

 
The water pump is a critical component of the cooling system. Any abnormal operation of the water pump can directly affect the flow rate and circulation effect of the cooling water. A malfunctioning water pump may result in reduced circulating water flow within the cooling system, leading to poor cooling efficiency and excessive coolant temperature. Preliminary judgment of the water pump's operation can be made by feeling the flow rate of the circulating water through the outlet hose connected to the radiator. If the flow rate increases steadily from idle to high speed, the water pump is operating normally; otherwise, further inspection for water pump malfunction is required.
 

3. Circulating System Pipeline Scaling and Blockage

 
Scaling and blockage in the circulating system pipelines are common faults in the cooling system. Accumulation of scale can obstruct the flow of cooling water, thus affecting the cooling effect. Scale mainly accumulates in the radiator, cylinder block, and water jacket. It is primarily composed of calcium carbonate and magnesium carbonate, which have poor heat transfer capabilities. Therefore, regular inspection of scale buildup in the circulating system, especially when using hard water containing a high concentration of calcium and magnesium ions, is essential to ensure the smooth operation of the cooling system.
 

4. Thermostat Malfunction

 
The thermostat is a crucial component of the cooling system, controlling the flow path of the cooling water to maintain the engine within the appropriate operating temperature range. A malfunctioning thermostat can affect the circulation of cooling water, resulting in abnormal coolant temperature. The operation status of the thermostat can be preliminarily judged by observing the initial temperature rise during engine operation and the temperature changes in the radiator. Additionally, the thermostat's operation can be further confirmed by checking the temperature at the radiator cap and drain valve during engine operation.
 

5. Fan Belt Abnormalities

 
Abnormal wear, slipping, or cracking of the fan belt can lead to a decrease in fan speed, affecting the cooling effect. Regular inspection of the fan belt's condition and timely adjustment or replacement of severely worn belts are essential to ensure the normal operation of the cooling system.
 
In conclusion, maintaining the normal operation of the cooling system of diesel generator sets is crucial for their long-term stable operation. Users should conduct regular inspections and maintenance, promptly identify and rectify faults to ensure the cooling system is in good working condition, thereby providing reliable operation of the generator set.