Essential Adjustment Guide for Diesel Generator Sets

 
Diesel generator sets are crucial backup power sources, essential for industrial production, commercial operations, and residential security. Ensuring their performance and reliability necessitates regular inspections and maintenance. This guide details the methods and considerations for adjusting oil pressure, regulators, valve clearance, fan belts, fuel supply advance angle, and decompression, all of which can extend the lifespan of diesel generator sets, enhance operational efficiency, and reduce the risk of failure.
 

1. Oil Pressure Adjustment

 
Diesel generator sets typically use two lubrication methods: pressure lubrication and splash lubrication. Proper oil pressure is vital for effective lubrication. Low oil pressure can result in poor lubrication, accelerating component wear; high oil pressure can increase oil consumption and potentially cause oil leakage. Therefore, maintaining oil pressure within the specified range during operation is crucial. Generally, the normal oil pressure for diesel generator sets should be between 2.5 and 4.5 bars. Oil pressure can be maintained by adjusting the oil pressure regulator or replacing the oil pressure sensor.
 

2. Regulator Adjustment

 
Regulating the charging current is critical for the proper functioning of diesel generator sets. Excessive charging current can overheat the battery and shorten its lifespan, while insufficient current can lead to inadequate charging and starting issues. When abnormal charging current is detected, the regulator’s current limit spring should be adjusted. The specific methods are as follows:
 

• If the charging current is too high, shorten the current limit spring to reduce the current.
• If the charging current is too low, lengthen the current limit spring to increase the current.
• Adjustments should be made carefully, gently touching the spring to avoid excessive force and prevent damage to the regulator.

 

3. Valve Clearance Adjustment

 
Adjusting valve clearance is essential for maintaining the performance of diesel generator sets. When replacing cylinder head gaskets and piston rings or re-tightening the cylinder head due to gasket leaks, valve clearance must be adjusted. Both excessive and insufficient valve clearance can impact engine efficiency:
 

• Excessive valve clearance causes delayed valve opening and closing, insufficient intake, poor exhaust, and increased engine noise.
• Insufficient valve clearance may prevent the valve from fully closing, leading to valve burning or leakage.
• Valve clearance should be adjusted when the engine is cold, following the manufacturer’s specified parameters to ensure optimal engine performance.

 

4. Fan Belt Adjustment

 
The tension of the fan belt is crucial for the cooling system of diesel generator sets. An overly tight fan belt can increase wear on the generator, water pump, and fan bearings, reducing their lifespan. Conversely, an overly loose belt can lead to insufficient fan airflow, affecting cooling efficiency, generator output voltage, and water pump flow. Adjusting the fan belt involves:
 

• Checking the belt tension, which should allow a deflection of about 10-15 mm when pressed in the middle.
• Adjusting the position of the pulley or using a tensioner to achieve the correct belt tension if it is too loose or too tight.

 

5. Fuel Supply Advance Angle Adjustment

 
Adjusting the fuel supply advance angle is vital for fuel efficiency and economic operation of diesel generator sets. This adjustment is typically necessary after 500 hours of operation or when the fuel injection pump regulator components are calibrated and reassembled. The adjustment steps are:
 

• Shut down the generator and remove the injector.
• Manually rotate the crankshaft to find the fuel supply advance point.
• Adjust the fuel supply advance angle according to the manufacturer’s specifications to ensure it is in the optimal position.
• Correctly adjusting the fuel supply advance angle can significantly improve fuel economy and reduce operating costs.

 

6. Decompression Adjustment

 
During the use of diesel generator sets, starting difficulties often arise due to cold weather or low battery power. In such cases, decompression via the intake valve can be used to lower the compression ratio, reducing starting resistance and aiding the engine start. The specific method is:
 

• Open the decompression valve to keep the intake valve open, thereby reducing compression resistance.
• After starting the engine, gradually close the decompression valve to restore normal compression.
• By implementing the above adjustments and maintenance practices, the operational efficiency and lifespan of diesel generator sets can be effectively enhanced, ensuring their stable performance and meeting various usage requirements.

 
In summary, the efficient operation of diesel generator sets depends on meticulous routine maintenance and adjustments. From oil pressure, regulator settings, valve clearance, and fan belt tension to fuel supply advance angle and decompression adjustments, each aspect is critical. Regular inspections and precise adjustments can prevent potential failures and ensure the generator sets perform as required in critical moments. Moreover, good maintenance habits not only extend the equipment's lifespan but also improve operational efficiency and reduce operational costs.