Is Engine Valve Noise Related to Engine Oil?

[EllaLee]

Engine valve noise is related to engine oil. The following are the reasons for engine valve noise: 1. Insufficient engine oil. When the engine oil level is insufficient, the oil level drops to a certain extent, allowing air to enter the hydraulic lifters through the oil passages, creating gaps and causing valve noise. 2. Air entering the oil passages during an oil change. When draining the oil, the oil in the passages is emptied, and air enters the passages. When starting the engine, this air may enter the hydraulic lifters, causing valve noise. In this case, after the engine runs normally for a while, the air will be expelled, and the valve noise will automatically disappear. 3. Sludge or carbon deposits in the oil passages. When sludge forms in the engine, it can clog the oil passages, causing the automatic gap adjustment function of the hydraulic lifters to fail, resulting in valve noise. 4. Incorrect oil viscosity selection. When the engine is severely worn, using oil with a low viscosity (e.g., 20 or 30 viscosity oil) can also cause valve noise. In such cases, switching to a higher viscosity oil (e.g., 40 or 50 viscosity oil) can eliminate the valve noise.