Oil-passage structure of internal combustion engine

An oil-passage structure of an internal combustion engine including a cylinder block provided with a plurality of auxiliaries having pulleys associated therewith, a crankshaft provided with a crank pulley and a crank timing sprocket and supported on the cylinder block, a cylinder head positioned on the cylinder block, intake and exhaust camshafts supported by the cylinder head for opening and closing an intake valve and an exhaust valve respectively, cam sprockets respectively attached to the intake and exhaust camshafts, a timing chain wound around the crank timing sprocket and the cam sprockets, a chain cover extending over the cylinder block and the cylinder head so as to cover the timing chain, an auxiliaries driving belt wound around the pulleys associated with the auxiliaries and around the crank pulley, an oil pump to be driven by the crankshaft, an oil control valve for operating hydraulic equipment whereby oil from the oil pump is introduced to the oil control valve, a belt tensioner for adjusting the tensile force of the auxiliaries driving belt, the belt tensioner being mounted on the chain cover by a tensioner bracket, and an external oil pipe interconnecting the oil pump and the oil control valve and arranged between the tensioner bracket and the chain cover.

The oil-passage structure as claimed in claim is 2, wherein said belt tensioner includes a pulley mounted on said tensioner bracket via first and second bolts respectively received in first and second bosses formed on a rear side of said tensioner bracket adjacent said chain cover, said oil pipe having an upper end connected to said oil control valve, a lower end connected to said chain cover and an intermediate portion disposed between said upper and lower ends, said intermediate portion being positioned between said first and second bosses at said rear side of said tensioner bracket.