The lubrication oil flow in an engine is in the order as

• oil strainer - oil pump - relief valve - oil filter - cylinder block - cylinder head - oil pan
• oil pump - oil strainer - relief valve - oil filter - cylinder block - cylinder head - oil pan
• oil strainer - oil filter - relief valve - oil pump - cylinder block - cylinder head - oil pan
• oil strainer - oil pump - relief valve - oil filter - cylinder head - cylinder block - oil pan