How to Test the Quality of Engine Oil?
2 Answers
Testing the quality of engine oil can be done through the following methods: 1. Visual inspection: Pour the oil into a transparent glass and observe. If the oil has good transparency, no suspended particles, no sediment, and no clumps of impurities, it is considered better quality; 2. Smell the oil: High-quality engine oil has a mild odor. If there is a strong, pungent smell, especially a heavy fuel odor, it is likely recycled oil; 3. Check the quality grade label: According to relevant standards, the further the letters in the quality grade label are in the alphabet, the better the performance of the oil; 4. Check the viscosity grade label: For oils of the same quality grade, the larger the difference between the numbers before and after the 'W' in the viscosity grade, the wider the applicable temperature range, indicating higher-performance engine oil.
Testing engine oil quality by yourself is quite simple, and I usually enjoy DIY car maintenance. The method is: after the engine warms up and you park, wait half an hour, pull out the dipstick, wipe it clean, reinsert it, then pull it out again to check the oil level and color. Good oil is light yellow, clear, and transparent; bad oil turns black or has impurities like sand particles. Another method is to use professional oil filter paper: drop a drop of oil on it, and if it spreads into a uniform light brown ring, it's good; a dark or irregular ring indicates severe oxidation, and it must be changed. Last month, I checked and found the oil was black, tested it, and then changed to new oil. Now, the engine starts more smoothly. Engine oil lifespan affects engine health, so I recommend testing it yourself every 5,000 kilometers or every six months to save a lot on repair costs.
