An internal combustion engine includes: a cylinder in which a piston reciprocates; a cylinder head positioned above the cylinder; a gasket disposed between the cylinder and the cylinder head; a stepped portion that is formed at an upper end portion of an inner peripheral surface of the cylinder and positioned below the gasket; a ring member having a cylindrical shape provided to the stepped portion; and a protrusion portion that is formed in a manner to protrude from the ring member and bites into a lower surface of the gasket.

An internal combustion engine includes: a cylinder in which a piston reciprocates; a cylinder head positioned above the cylinder; a gasket disposed between the cylinder and the cylinder head; a stepped portion formed at an upper end portion of an inner peripheral surface of the cylinder; a ring member having a cylindrical shape provided to the stepped portion; and a seal member that is provided on an upper surface of the ring member and is sandwiched between the ring member and the cylinder head.

An apparatus is provided to test valves. The apparatus includes an actuation mechanism having an actuator that seals a valve of a combustion chamber of an engine. The apparatus further includes a flow control device that controls a flow of a pressurized fluid to the combustion chamber. The apparatus further includes a plurality of sensors having a first sensor and a second sensor. The first sensor is disposed in an inlet port of the combustion chamber to detect a first flow rate of the pressurized fluid in the inlet port. The second sensor is disposed in an exhaust port of the combustion chamber to detect a second flow rate of the pressurized fluid in the exhaust port. The apparatus further includes a notification device configured to generate an alert based on the detected first flow rate and the detected second flow rate.

A cylinder head (1) disclosed herein includes a cylinder head main body (10) having an intake port (3) communicating with a combustion chamber (2) of an engine; and an insulation member (20) being arranged at an inner side of the intake port (3), made of resin, and formed into an annular shape. A step part (14) is formed at a downstream side of the insulation member (20) in a flow direction of intake air in the intake port (3) such that the intake port (3) has a cross section perpendicular to the flow direction at the downstream side smaller than a cross section perpendicular to the flow direction at an upstream side of the flow direction; and an annular seal member (21) that seals a space between the insulation member (20) and the step part (14) is arranged between the insulation member (20) and the step part (14).

An engine comprises a housing and a combustion assembly carried by the housing. The combustion assembly comprises an annular bore defined by the housing, at least one combustion piston disposed within the annular bore, and a sealing mechanism configured to selectively seal the at least one combustion piston relative to at least one corresponding wall of the annular bore. The engine comprises at least one rotary valve configured to move between a first position within the annular bore to allow the at least one combustion piston to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one rotary valve and a second position within the annular bore to define a combustion chamber relative to the at least one combustion piston at the second location.

An internal combustion engine and a head gasket are provided. The internal combustion engine includes a block having at least one cylinder, a head joined to the block at a head interface, a cooling fluid circulation passage extending at least partially through the head and the block and having a first portion disposed in the head and a second portion disposed in the block, a head gasket having a plate extending across the head interface and separating the first portion of the cooling fluid circulation passage from the second portion of the cooling fluid circulation passage, and a plurality of orifices extending through the plate. The plurality of orifices is aligned with the cooling fluid circulation passage and is configured to control a flow of cooling fluid circulating between the first portion of the cooling fluid circulation passage and the second portion of the cooling fluid circulation passage.

An engine includes a housing and a combustion assembly. The combustion assembly includes an annular bore and a combustion piston assembly disposed within the annular bore. The combustion piston assembly includes a set of pistons, a first sealing ring connected to each piston and a second sealing ring connected to each piston. The second sealing ring is configured to provide selective access between the annular bore and at least one fluid conduit carried by the engine. The engine includes at least one valve configured to move between a first position within the annular bore to allow the combustion piston assembly to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position within the annular bore to define a combustion chamber.

A gasket is described herein. The gasket might be used between internal combustion engine components. The gasket might be comprised of metal. The gasket might have several layers including a sealing layer and a compression layer. The gasket includes sections having different radii of curvature. The different radii of curvature might have particular relationships to one another.

Systems are provided for cooling a cylinder block via bore bridge cooling passages. In one example, a cylinder block with a bore bridge positioned between a first cylinder and a second cylinder, the cylinder block also including a coolant jacket at least partially surrounding the first cylinder and the second cylinder, has at least one cooling passage positioned within the bore bridge. An inlet of the at least one cooling passage has a larger area than an outlet of the at least one cooling passage and at least a portion of the at least one cooling passage has a non-cylindrical geometry formed by a lost core.

Various systems and methods are provided for utilizing a crankshaft lip seal over the course of a first overhaul life and a second overhaul life. In one example, a method includes installing the crankshaft lip seal between a flywheel housing and a crankshaft of an engine and operating the engine with the crankshaft lip seal. The method further includes removing the crankshaft lip seal, re-machining a floating seal sleeve coupled to the crankshaft or the flywheel housing, and replacing a lip. The crankshaft lip seal is then re-installed between the flywheel housing and the crankshaft and the engine operated with the re-installed crankshaft lip seal.