Abstract: An internal combustion engine, of the type having a block with a line of cylinders and a cylinder head attached to the block and coolant distribution and discharge manifolds provided adjacent each other on one side of the block is provided with an improved coolant arrangement. Coolant from a pump enters the distribution manifold at a point intermediate the ends of the line of cylinders and from there flows freely up into the cylinder head through cast openings corresponding in number to the number of cylinders. The majority of coolant flows across the cylinder head and down to coolant chambers surrounding the engine cylinders via a pair of orificed holes for each cylinder. The orificed holes control the flow of coolant around the cylinders and are provided in a gasket between the cylinder block and cylinder head. After the coolant flows around the cylinder liners, it is discharged from the coolant chambers in the cylinder block to the discharge manifold via a cast opening for each cylinder.