Answer for How and when do we change oil of an engine?

The engine oil should generally be changed when the vehicle has completed about 5000 kms. First of all the engine should be started till it becomes hot and by opening the drain plug, oil of the oil chamber should be released. After fitting the plug some flushing oil should be put and the engine should be cranked. Now this dirty oil should also be emptied and new oil should be filled in. At the time of changing the oil, oil of air cleaner should also be changed.