The invention relates to an oil decantation system (1) comprising: (i) a separator device (6) designed to trap the oil droplets (107) that are present in a flow of a blow-by gas (110); and (ii) a jet pump (5) positioned upstream of the separator device (6) and designed to accelerate and draw the flow of the blow-by gas (110) before it enters said separator device (6).

Methods for indicating whether a crankcase of an engine is breeched are provided. One example method comprises restricting a communication of the crankcase with atmosphere, acting to increase or decrease a crankcase pressure, and indicating whether the crankcase is breeched based on the crankcase pressure. Another example method comprises sensing a crankcase pressure component, and indicating whether the crankcase is breeched based on the crankcase pressure component, the crankcase communicating with atmosphere via a conduit, a restrictedness of the conduit responsive to one or more of a crankcase pressure and a signal from an electronic control unit of the motor vehicle. Still other examples provide more particular methods for indicating whether the crankcase is breeched, and example configurations that enable the various methods.

Apparatuses, systems and methods for utilizing crankcase compression air to effect forced air induction (i.e. boost) into the combustion chamber of an internal combustion engine is provided. In some embodiments, the apparatuses are a supercharger apparatus that is attached to an existing engine. In other embodiments, the supercharger components are located within the structure of a novel engine itself. An embodiment of the apparatus includes a conduit that includes three inlets: 1) an inlet that is capable of being placed in fluidic communication with the crankcase chamber of an engine; 2) an inlet that is capable of being placed in fluidic communication with an intake to a combustion chamber of the engine; and 3) an inlet in fluidic communication with the atmosphere.

An abnormality assessment device includes an on-off valve that shuts an intake path on an upstream side of a connection portion of a breather line with respect to the intake path and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a difference between an intake flow rate that is detected by an intake flow rate sensor and a target intake flow rate in a case where the on-off valve is closed.

An internal combustion engine includes on-off valves that configure a closed space by closing an internal space of a breather line, a pump that depressurizes or pressurizes the closed space, a pressure sensor that detects a pressure of the closed space, and an abnormality assessment element that assesses abnormality of the breather line. The abnormality assessment element assesses abnormality of the breather line based on a pressure change of the closed space in a case where the closed space is depressurized or pressurized by the pump.

A method for ventilating a crankcase of an internal combustion engine using natural gas as a fuel source may include filtering ambient air through an air filter. The method may also include heating the filtered ambient air by a jacket heat exchanger. The method may further include directing the heated ambient air through an inlet of the crankcase to purge blow-by gases including natural gas from the crankcase.

Systems and methods (e.g., a method for controlling and/or operating a compressor) are provided that includes the steps of monitoring a crankcase pressure of a first compressor; analyzing the monitored crankcase pressure that includes calculating an average of the crankcase pressure over a time period and comparing the average of the crankcase pressure over the time period to a nominal crankcase average pressure; identifying a condition of the first compressor based on the analysis of the monitored crankcase pressure; and adjusting operation of a second compressor to compensate for the first compressor in response to identifying the condition of the first compressor based on the analysis of the monitored crankcase pressure. (The method may be carried out automatically or otherwise by a controller).

A blow-by gas purge apparatus includes: a positive crankcase ventilation (PCV) valve disposed on a cylinder head; a head passage penetrating on the cylinder head to communicate with a discharge side of the PCV valve; and a port adaptor interposed between the cylinder head and an intake manifold. The port adaptor includes: multiple intake communication holes such that each intake runner of the intake manifold communicates with each intake port of the cylinder head; an inlet hole communicating with the head passage; and a distribution passage dividing and supplying blow-by gases introduced through the inlet hole into the multiple intake communication holes.

A positive crankcase ventilation (PCV) system includes: an oil separator separating oil from blow-by gases; a PCV valve allowing the blow-by gases from which the oil has been separated by the oil separator to flow into intake ports of a cylinder head; a PCV passage vertically extending from the PCV valve; a PCV chamber connected to the PCV passage; and a plurality of bypass passages branching off from the PCV chamber to the intake ports, respectively.

A blow-by gas purge apparatus includes: a positive crankcase ventilation (PCV) valve disposed on a cylinder head; a head passage penetrating on the cylinder head to communicate with a discharge side of the PCV valve; and a port adaptor interposed between the cylinder head and an intake manifold. The port adaptor includes: multiple intake communication holes such that each intake runner of the intake manifold communicates with each intake port of the cylinder head; an inlet hole communicating with the head passage; and a distribution passage dividing and supplying blow-by gases introduced through the inlet hole into the multiple intake communication holes.