Methods and systems are provided for using a crankcase vent tube pressure or flow sensor for diagnosing a location and nature of crankcase system integrity breach. The same sensor can also be used for diagnosing air filter plugging and PCV valve degradation. Use of an existing sensor to diagnose multiple engine components provides cost reduction and sensor compaction benefits.

A positive crankcase ventilation (PCV) valve mounting structure has a blow-by gas passage with an upstream-side passage portion and a down-stream-side passage portion positioned in a cylinder head and an intake manifold, respectively. The blow-by gas passage may receive the PCV valve therein such that an upstream side portion of a valve case of the PCV valve is positioned within the upstream-side passage portion and that a downstream side portion of the valve case is positioned within the down-stream-side passage portion when the cylinder head and the intake manifold are joined together. A gasket may seal the cylinder head to the intake manifold and may include a seal portion positioned between the valve case of the PCV valve and at least one of the cylinder head and the intake manifold.

In a multi-fuel system for diesel engines, natural gas is mixed with diesel fuel and conditioned in a mixing chamber before being injected into the mixing chamber of the engine. Filtered blow-by gas may also be introduced into the combustion chamber. A computerized controller is used to determine and control the proportion of diesel fuel, natural gas fuel, the mixing and conditioning of these fuels, and the supply of filtered blow-by gas.

A switching membrane for a pressure control valve has a plate-shaped flat body with a central area and a bending area surrounding the central area. The central area is provided with a closure area. For switching the switching membrane, the central area can be moved back and forth by a bending movement of the bending area in a direction transverse to an extension of the central area. At least the bending area is made of fluorocarbon rubber. A pressure control valve, especially for crankcase ventilation, is provided with a valve housing that has a housing cover and further is provided with a valve seat. A switching membrane as described above is disposed in the valve housing and switches at pressure differences of at most 500 mbar to release or shut off a flow of fluid at the valve seat.

An actuator for a separator for separating contaminants from a fluid stream which includes entrained contaminants. The actuator is arranged to move along an actuator axis to adjust an open cross-sectional area of at least one aperture of the separator, and comprises a flexible diaphragm, and a support assembly for the flexible diaphragm. The support assembly is movable along the actuator axis carrying the flexible diaphragm and has an upper support member mounted on a lower support member. A portion of the flexible diaphragm is located between the upper and lower support members. The lower support member comprises an axially extending support portion coupled to a radially extending support portion. The upper support member comprises a diaphragm anti-inversion feature coupled to a radially extending support portion. The diaphragm anti-inversion feature extends such that it axially overlaps at least part of the axially extending support portion of the lower support member.

An internal combustion engine has a control device, an EGR valve that adjusts an EGR rate, a PCV valve that adjusts an opening degree of a first PCV passage that communicates an inside of a crankcase and a downstream side of a throttle valve. The control device operates the throttle valve in a closing direction in response to a deceleration request. The control device adjusts an opening degree of the PCV valve based on an immediately preceding EGR rate immediately before reception of the deceleration request.

A pressure-limiting valve for use in a gas line conveying a gas that includes aerosols. The pressure-limiting valve has a movable valve body, a valve seat, and a compressible coalescing medium placed therebetween. The valve body has passages and nozzle openings and the valve seat has through-holes. In the closed position, the valve functions in separator mode and in the fully open position, in impactor mode. The pressure-limiting valve according to the invention provides a more sensitive response to varying flow conditions, due to deviating surface profiles of the valve seat and coalescing medium, which provide intermediate stages of separator and impactor modes as a function of the volume of flow.

A PCV valve that regulates the flow of gases to a turbocharger. A spring biased plunger member is used to restrict and meter the flow of gases through the PCV valve. The plunger member can include an axially extending through opening extending through the length of the plunger member to allow back flow of gases to be routed to the turbocharger. The through opening can be selectively opened and closed by a valve module contained in the plunger member.

To provide an electromagnetic valve capable of preventing damage due to stress of a buffer member. An electromagnetic valve includes a solenoid having a case, a flow path member, and a columnar valve element that is housed in the valve element housing portion of the flow path member and moves with a plunger of the solenoid to open and close a flow path. A seat member with which the plunger comes into contact is disposed in the case of the solenoid. The seat member includes a core portion with which the plunger comes into contact, and a plurality of protruding portions protruding radially outward from an outer peripheral surface on the radially outer side of the core portion.

A two-stroke internal combustion engine has a crankshaft disposed at least in part in a crankcase, and a cylinder block connected to the crankcase and defining a cylinder. The cylinder defines at least one exhaust port for discharging exhaust fluid. A piston is movably disposed within the cylinder and is operatively connected to the crankshaft. The piston is movable along a cylinder axis in a reciprocating motion including an upstroke and a downstroke. An exhaust valve assembly is operatively connected to and rotates with the crankshaft. The exhaust valve assembly has a shaft rotatably supported by the cylinder block and a valve configured to cyclically obstruct the exhaust port. The valve is operable to move clear of the exhaust port before the piston uncovers the exhaust port during its downstroke, and at least partially close the exhaust port before the piston fully covers the exhaust port during its upstroke.