What Causes the Abnormal Noise in the Jinjila 300 Engine?

[LeHolden]

The causes of abnormal noise in the engine include premature fuel injection, diesel leakage from the injector, piston hitting the cylinder wall, excessive piston ring side clearance, impact between the valve stem head and rocker arm, and engine misfire. The specific cause needs to be determined based on different noise conditions, as detailed below: Abnormal noise caused by rough engine operation, commonly known as "knocking sound." The phenomenon is that the sound is strong at low speeds and can be heard clearly from a distance of more than ten meters away, accompanied by difficulty in starting. After the engine ignites, it runs unevenly, and the cooling water consumption is rapid. This abnormal noise is caused by premature fuel injection, and the fuel injection timing should be readjusted. The engine noise has a certain pattern, sometimes knocking, sometimes backfiring, accompanied by unstable engine speed and intermittent black smoke emissions. This uneven noise is caused by diesel leakage from the injector. When this phenomenon occurs, the injector should be serviced. The engine emits a "thumping" or "thumping" knocking sound, which is particularly noticeable at low speeds or sudden changes in speed, accompanied by oil burning. This noise is caused by excessive clearance between the piston and the cylinder wall, which increases the piston's impact on the cylinder wall when the diesel engine is working. The solution is to replace the cylinder liner or piston. A "clanging" sound similar to a small hammer lightly tapping an anvil can be heard throughout the entire length of the cylinder block, and the sound becomes more noticeable when the engine speed changes suddenly. This is caused by excessive piston ring side clearance. The piston rings should be replaced, and the piston may need to be replaced as well if necessary. A "clicking" or "clicking" knocking sound is heard around the cylinder head cover. The sound is smaller when the engine is hot and louder when cold, and it does not disappear when the fuel supply is stopped at low speeds. The main reason is excessive valve clearance, causing the valve stem head to impact the rocker arm. The valve clearance should be adjusted. The exhaust gas flow from the car shows obvious intermittency, and the exhaust pipe shakes violently, with clear abnormal engine noise. This is caused by engine misfire.