Engine assembly with engine block-integrated cooling system

An engine assembly comprising:

• a cylinder head;
• a generally V-shaped engine block connected to the cylinder head having a first and a second row of cylinder bores and a valley between the rows of cylinder bores, and
• defining an oil flow passage containing oil flowing from the cylinder head to an oil sump;
• a coolant pump mounted to the engine block;
• wherein the engine block defines coolant flow passages that direct coolant from the coolant pump through the engine block for cooling the engine;
• wherein the coolant flow passages include a first coolant flow passage and a second coolant flow passage generally parallel with one another and each extending along a length of the engine block past multiple ones of the cylinder bores of the first row of cylinder bores;
• wherein the first and second coolant flow passages are sufficiently adjacent to the oil flow passage such that the coolant flowing in the first and second coolant flow passages cools the oil flowing in the adjacent oil flow passage by heat transfer through the engine block;
• wherein the oil flow passage has a first portion generally above the first coolant passage, a second portion generally below the first coolant passage, and an elbow portion connecting the first portion and the second portion;
• wherein the elbow portion is positioned in the engine block outside of the valley and wherein the elbow portion is configured to function as a reservoir to hold at least some of the oil that has flowed through the first portion and past the first coolant flow passage prior to flowing in the second portion between the first and the second coolant flow passages.

A cooling system for an engine assembly comprising:

• A generally V-shaped engine block having a first row and a second row of cylinder bores and a valley between the rows of cylinder bores;
• wherein the engine block defines a first coolant flow passage extending along a length of the engine block past multiple ones of the cylinder bores of the first row of cylinder bores and configured to carry coolant through the engine block;
• wherein the engine block defines an oil flow passage configured to carry lubricating oil through the engine block;
• wherein the oil flow passage at least partially surrounds the first coolant flow passage and is sufficiently adjacent to the first coolant flow passage such that the lubricating oil flowing in the oil flow passage is cooled by the coolant flowing in the first coolant flow passage by heat transfer through the engine block;
• wherein the engine block further defines a second coolant flow passage extending past said multiple ones of the cylinder bores of the first row of cylinder bores along the length of the engine block and generally parallel to the first coolant flow passage and positioned so that the oil flow passage passes between the first and the second coolant flow passages;
• wherein the first coolant flow passage directs coolant around the cylinder bores of the first row of cylinder bores and the second coolant flow passages direct coolant flow to the cylinder head;
• wherein the oil flow passage has a first portion generally above the first coolant passage, a second portion generally below the first coolant passage, and an elbow portion connecting the first portion and the second portion;
• wherein the elbow portion is positioned in the engine block outside the valley;
• and wherein the elbow portion is configured to function as a reservoir to hold at least some of the oil that has flowed through the first portion and past the first coolant flow passage prior to flowing in the second portion between the first and the second coolant flow passages.