Cylinder block structure for V-type engine

摘要

A cylinder block for a V-type engine having a left bank and a right bank. A valley is defined between the two blocks. A stepped section is defined in the valley. The stepped section extends in the longitudinal direction of the valley. A cover plate is fixed to the stepped section to define a coolant passage which coolant flows through. A main oil passage is defined in the cylinder block extending parallel to the coolant passage. The valley includes a projection that projects into the coolant passage. A oil cooling passage is defined in the projection. An opening of the cooling passage is connected with the main oil passage. An opening of a bearing oil passage, which lubricating oil for a crankshaft is supplied through, is also connected with the main oil passage. Rotation of the crankshaft produces pressure fluctuation in the bearing oil passage. The opening of the cooling passage is located on the other side of the main oil passage at a position opposed to the opening of the bearing oil passage. The pressure fluctuation in the bearing oil passage is transmitted to the cooling passage in the projection to produce a flow of lubricating oil therein.