What are the symptoms of excessively thin engine oil?

[MaddoxLee]

Engine oil is composed of a base oil blend made from petroleum-based hydrocarbons, polyalphaolefins (PAO), or mixtures of these in varying proportions. Excessively thin engine oil can lead to the following two conditions: 1. Insufficient oil pressure, resulting in semi-dry or dry friction between various friction components, and in severe cases, can cause bearing seizure. 2. It can cause excessive engine noise. The reasons for engine oil becoming too thin include: 1. Malfunctions in the fuel supply system or poor fuel atomization, allowing fuel or large amounts of overly rich fuel mixture to enter the crankcase and mix with the oil, thus thinning the oil. 2. Prolonged engine idling or repeated starting, causing fuel mixture to enter the crankcase and thin the oil. 3. Oil leakage from the forced-lubrication fuel injection pump or fuel transfer pump, leading to oil thinning. 4. Cylinder wall wear causing changes in cylinder diameter, piston ring damage, or improper piston ring installation, resulting in oil thinning.