Common faults of diesel generator sets

Understanding the structural principles of diesel engines is crucial for their effective operation. It is equally important to know the conditions under which a diesel engine can run smoothly. When a fault occurs, diagnosing the issue based on the symptoms is essential. Through thorough analysis, we can identify the correct solutions and resolve the faults effectively.

1. Diesel Engine Fails to Start

Under normal conditions, a

Fault Phenomenon

Diesel engine cannot start.

Fault Causes

• Insufficient starting battery.
• Incorrect wiring in the starting system or poor contact of electrical components.
• Carbon brush of the starting motor not making proper contact with the commutator.

Troubleshooting Methods

• Replace the battery with a fully charged one or connect an additional battery in parallel.
• Verify that the wiring of the starting circuit is correct and reliable.
• Repair or replace the carbon brush; clean the commutator’s surface with wood sandpaper, and blow off any dust.

2. High Cooling Water Temperature

Firstly, ensure that the radiator surface of the cooling water tank is clean, as dust can block it, especially in a dusty environment. Debris may also enter the water tank, hindering airflow and causing poor heat dissipation. Cleaning the radiator surface or removing debris can solve this issue. Secondly, check for sufficient coolant in the cooling water tank and determine the cause of any coolant loss. Inspect the cooling water pipes for leaks and repair any issues found. Then replenish coolant to the normal level. Thirdly, if the thermostat fails to open, it can restrict the circulation flow of cooling water. This can be remedied by replacing the thermostat.

3. Black Smoke from the Generator Set Exhaust

Black smoke typically results from poor fuel quality, which may contain impurities. These impurities can clog the injector, leading to incomplete combustion in the cylinder. High pressure in the injector may also damage the nozzle, resulting in further complications. Damaged injectors will continue to emit black smoke, even with good quality fuel. Therefore, it is crucial to control fuel quality to enhance engine longevity. Additionally, dust in the environment can block the air filter, restricting the airflow necessary for combustion. Cleaning or replacing the air filter can rectify this issue. Also, improper injection timing can contribute to black smoke, and it is advisable to contact the manufacturer for adjustments to injection timing and valve clearance.

4. Blue Smoke from the Diesel Generator Exhaust

Blue smoke often indicates an overfilled oil filter (excess oil during maintenance). This can be corrected by reducing the oil to the specified level. Moreover, worn or stuck piston rings can result in oil leaking into the combustion chamber, leading to combustion issues. In such cases, it is recommended to contact the manufacturer for cleaning or replacing the piston rings.