Post by Rick Sanders on Dec 3, 2007 13:34:34 GMT -3
The inner circle indicates the condition of the oil itself. In gasoline engines, the older the oil, the darker brown the inner circle will be. In diesel engines, the result will be light grey to black. If there is much sediment in the engine, there will not be much difference between the centre spot and the inner circle. If the oil is in good condition, but the engine’s combustion produces alot of sediment, then another layer is formed around the inner circle which will be lighter in colour. This is a very good indication if your engine has problems with combustion.
