6. The cooling and lubrication system is faulty
Overheating of the diesel engine is caused by a fault in the cooling or lubrication system. In this case, the water temperature and oil temperature will be too high, and the cylinder or piston ring may become stuck. When the diesel engine exhaust temperature increases, the cooler and radiator should be inspected and scale removed.
7. The cylinder head group is faulty
(1) Due to exhaust leakage, the intake air volume is insufficient or the intake air is mixed with exhaust gas, which in turn leads to insufficient fuel combustion and reduced power. The mating surface of the valve and valve seat should be ground to improve its sealing performance, and replaced with new ones if necessary.
(2) Air leakage at the joint surface between the cylinder head and the engine body will cause the air in the cylinder to enter the water channel or oil channel, causing the coolant to enter the engine body. If it is not discovered in time, it will cause “sliding tiles” or black smoke, thus damaging the engine. Lack of motivation. Due to damage to the cylinder gasket, an airflow will rush out from the cylinder gasket when shifting gears, and blisters will appear on the gasket when the engine is running. At this time, the cylinder head nut should be tightened to the specified torque or the cylinder head gasket should be replaced.
(3) Incorrect valve clearance will cause air leakage, resulting in reduced engine power and even difficulty in ignition. The valve clearance should be readjusted.
(4) Damage to the valve spring will cause difficulty in valve return, valve leakage, and reduced gas compression ratio, resulting in insufficient engine power. Damaged valve springs should be replaced promptly.
(5) Air leakage in the injector mounting hole or damage to the copper pad will cause cylinder shortage and insufficient engine power. It should be disassembled for inspection and damaged parts should be replaced. If the inlet water temperature is too low, heat dissipation loss will increase. At this time, the inlet temperature should be adjusted to meet the specified value.
8. The surface of connecting rod bearing and crankshaft connecting rod journal is rough.
This situation will be accompanied by abnormal sounds and a drop in oil pressure. This is caused by the oil passage being blocked, the oil pump being damaged, the oil filter being blocked, or the oil hydraulic pressure being too low or even no oil. At this time, you can disassemble the side cover of the diesel engine and check the side clearance of the big end of the connecting rod to see if the big end of the connecting rod can move forward and backward. If it cannot move, it means that the hair has been bitten, and the connecting rod bearing should be repaired or replaced. At this time, for a supercharged diesel engine, in addition to the above reasons that will reduce the power, if the supercharger bearing is worn, the air intake pipeline of the press and turbine is blocked by dirt or leaks, the power of the diesel engine can also be reduced. When the above situation occurs in the supercharger, the bearings should be repaired or replaced respectively, the intake pipe and shell should be cleaned, the impeller should be wiped clean, and the joint nuts and clamps should be tightened.
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Post time: Apr-16-2024