1. Poor sealing between piston and cylinder liner: During low load operation, the sealing between the piston and cylinder liner deteriorates, causing oil to enter the combustion chamber and burn, resulting in blue smoke from the exhaust.
2. Decreased sealing effect of turbocharger oil seal: For turbocharged diesel engines, low load operation will cause a decrease in boost pressure, resulting in a decrease in the sealing effect of the turbocharger oil seal. Oil will enter the boost chamber and enter the cylinder along with the intake air.
3. Carbon deposition problem: Some engine oil participates in combustion, and the oil that has not been completely burned forms carbon deposits in the valves, intake passages, piston tops, piston rings, etc., causing oil and carbon deposits to accumulate in the cylinder exhaust passages, affecting engine performance.
4. Accumulation of oil in the turbocharger: When the oil in the turbocharger chamber accumulates to a certain extent, it will leak out from the joint surface of the turbocharger.
5. Increased wear of moving parts: Long term low load operation can lead to increased wear of moving parts, deterioration of engine combustion environment, and may result in an earlier overhaul period.
Preventive measures and solutions:
1. Pre start inspection: Before each start, check whether the cooling water or antifreeze is sufficient, whether the engine oil is within the specified scale line, and ensure that there are no hidden faults.
2. Idle running time control: After starting the diesel engine, it should idle for 3-5 minutes, and extend it for a few minutes appropriately in winter. Pay attention to whether the oil pressure is normal, and only operate normally if there are no abnormal conditions.
3. Avoid prolonged low load operation: Try to minimize low load/no-load operation time, and low load operation should not be lower than 25% -30% of the rated power of the unit. Avoid prolonged low idle or no-load operation for more than 10 minutes.
