A cylinder liner for internal combustion engines has an outer roughened surface that has particularly good adherence properties. The surface has is covered with protrusions or spines of varying shapes and sizes, which are created by spraying the mold with a coating and then casting the cylinder liner in the mold. The spines are generally conical or needle-shaped, with the bases being larger than the tips. The spines have an aggregate cross-sectional surface area measured at 0.2 mm from a ground cylindrical surface that is between 50-90% of the total ground cylindrical surface area, and an aggregate cross-sectional surface area measured at 0.4 mm from the ground cylindrical surface that is between 20-45% of the total ground cylindrical surface area.

A robust engine assembly having reduced weight and efficient cooling, without an increase in fuel consumption or carbon dioxide emissions, is provided. The engine assembly includes a double-wall cylinder liner clamped between a cylinder head and a crankcase. A manifold is disposed along a portion of the cylinder liner and includes fluid ports aligned with fluid ports of the cylinder liner to convey cooling fluid to a cooling chamber located between the walls of the cylinder liner. For example, the manifold can be a low-loss hydraulic manifold cast integral with the crankcase. Tie rods connect the cylinder head to the crankcase to clamp the cylinder liner in position. Alternatively, the tie rods can be connected to a main bearing cradle located beneath the crankcase. No attachment features extend into the walls of the cylinder liner, which is especially advantageous when the cylinder liner is formed of aluminum.

In a method for manufacturing a cylinder block provided with cylinder bores, the cylinder block is held by a clamp device, stress is generated in the cylinder block by a holding force of the clamp device to duplicate deformations of the cylinder bores after assembling hearing caps thereon, boring is carried out with the cylinder bores deformed in a condition where the stress is generated, and a thermally sprayed coating is formed, after the boring, on each inner surfaces of the cylinder bores deformed in the condition where the stress is generated. According to the method for manufacturing a cylinder block, superior cylindricity, after assembling the bearing caps, of the cylinder bores on each of which the thermally sprayed coating is formed can be brought, and workability degradation of finishing works (honing) for each inner surface of the cylinder bores (thermally sprayed coatings) can be restricted.

A seal assembly that includes a substantially annular cylindrical configuration that defines an aperture that defines a cylindrical axis and a radial direction is provided. The seal assembly comprises a spring member that includes two arm portions that extend substantially in a direction that is parallel to the cylindrical axis and that meet forming a flex point, and a sealing member that at least partially encapsulates the spring member and that includes: a first sealing feature, and a second sealing feature that is positioned axially and radially adjacent the flex point of the spring member and that faces in a direction that is diametrically opposite the direction that the first sealing feature faces along the radial direction, and an elastomeric material that includes a base resistant type 5 fluoroleastomer made from a copolymer of propylene and tetrafluoroethylene.

A cylinder for opposed-piston engines includes a liner with a bore and longitudinally displaced intake and exhaust ports near respective ends thereof. An intermediate portion of the liner between the exhaust and intake ports contains a combustion chamber formed when the end surfaces of a pair of pistons disposed in opposition in the bore are in close mutual proximity. A compression sleeve encircles and reinforces the intermediate portion of the liner. An annular grid of pegs disposed between the intermediate portion and the compression sleeve supports the compression sleeve against the liner and defines a turbulent liquid flow path extending across the intermediate portion in a direction that parallels the longitudinal axis of the liner.

An object of the present invention is to provide a cylinder liner for insert casting that can improve the joining strength between a cylinder liner and a cylinder block by reducing voids generated between the cylinder liner and the cylinder block. The above-described problem can be solved when the molten metal running index YI defined by the following Formula (1) is from 2.2 to 14.5.
Molten metal running index YI=[area ratio S.sub.t (%) of top portions of protrusions×molten metal infiltration volume V (mm.sup.3)/surface area A (mm.sup.2) of cylinder liner base]/average surface-to-surface distance P.sub.av between top portions of protrusions (mm)  (1).

An internal combustion engine includes a cylinder head and a cylinder block. The cylinder head includes a first boss cylinder head conduit portion and a first boss cylinder head cavity portion. The first boss cylinder head conduit portion is configured to receive a first fastener without threadably engaging the first fastener. The first boss cylinder head conduit portion has a first diameter. The first boss cylinder head cavity portion is aligned with the first boss cylinder head conduit portion. The first boss cylinder head cavity portion is configured to receive the first fastener without threadably engaging the first fastener. The first boss cylinder head cavity portion has a second diameter greater than the first diameter. The cylinder block is coupled to the cylinder head. The cylinder block includes a first boss cylinder block threaded portion.

A method of forming an engine component includes providing a cylinder liner main body having a curved interior wall forming a cylinder bore extending along a bore axis and a curved exterior wall formed circumferentially about the curved interior wall. The method includes disposing a coating layer onto the interior wall and the exterior wall. A cylinder liner is provided that includes a main body and a coating layer disposed on an exterior wall and on an interior wall of the main body.

A method of forming an engine component includes providing a cylinder liner main body having a curved interior wall forming a cylinder bore extending along a bore axis and a curved exterior wall formed circumferentially about the curved interior wall. The method includes disposing a coating layer onto the interior wall and the exterior wall. A cylinder liner is provided that includes a main body and a coating layer disposed on an exterior wall and on an interior wall of the main body.

An internal combustion engine includes a cylinder head and a cylinder block. The cylinder head includes a first boss cylinder head conduit portion and a first boss cylinder head cavity portion. The first boss cylinder head conduit portion is configured to receive a first fastener without threadably engaging the first fastener. The first boss cylinder head conduit portion has a first diameter. The first boss cylinder head cavity portion is aligned with the first boss cylinder head conduit portion. The first boss cylinder head cavity portion is configured to receive the first fastener without threadably engaging the first fastener. The first boss cylinder head cavity portion has a second diameter greater than the first diameter. The cylinder block is coupled to the cylinder head. The cylinder block includes a first boss cylinder block threaded portion.