To seal an oil leak, first identify the leaking part. Spray an engine degreaser on the engine dirty parts to clean it. Rinse the engine with clean water, and give it enough time to dry. A clean engine should be a good guide in locating a secondary leak, apart from the only obvious leak from an oil pan bolt.
If the bolt is the source of the leak, change the oil pan bolt basket to remedy the issue. Slide the gasket over the bolt to install, and secure it firmly according to manufacturer guidelines. Change the oil pan gasket, and drain the engine oil.
Pull out the oil pan by loosening the bolts that hold the pan in place. Take out the old gasket, and remove the oil sludge by cleaning the oil pan with brake cleaner and paper towel. Use a chisel to remove traces of old oil pan gaskets. Change the oil pan, and put the new gasket. Refill the vehicle with oil.
If there is leakage in the oil filter seal, replace it to solve issue. To do this, loosen the old oil filter to remove it, and clean the surface where it was in contact with the engine. Apply a thin layer of new oil on the oil filter gasket before installing another oil filter. Add a seal sweller to prevent the oil from leakage.