INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide an internal combustion engine that can suppress the temperature rise of lubricant oil when the lubricant oil accumulated at an upper deck of a cylinder head is returned to an oil pan.SOLUTION: A return oil path 60 for returning oil from an upper deck 50 to an oil pan 24 includes: a first oil path 61 whose upper end opens to the upper deck 50 and at least a part of which is adjacent to a water jacket 14A of a cylinder block 11; and a second oil path 62 connected with a lower end of the first oil path 61 and diametrally expanding the first oil path 61 over whole circumference. Further, a throttling part 64 is provided at the lower end of the first oil path 61.