A ventilation apparatus of an internal combustion engine of the invention ventilates a chain chamber by recirculating blow-by gas to an intake passage through a blow-by gas recirculation pipe and introducing air into the chain chamber through an air introduction pipe. The air introduction pipe is secured to a head cover wall portion which corresponds to a portion of a head cover wall which defines the chain chamber.

A valve has a valve housing with a valve seat and a valve body holder with a fluid-permeable flow opening. A valve body is arranged in the valve body holder and axially displaceable between an open state and a closed state of the valve. The valve body has an envelope surface with a sealing region for fluid-tightly contacting the valve seat in the closed state. It has a base region adjoining the sealing region in longitudinal direction. A cross section contour of the envelope surface increases monotonously from the sealing region to the base region. In the open state, an axial end of the base region contacts the valve body holder. The envelope surface has a weakened region connecting sealing region and base region to each other. The weakened region has a reduced stiffness along the longitudinal direction. The valve body is formed of a thermoplastic polyhalogen olefin.

An internal combustion engine may be used to compress natural gas for vehicle fuel. The engine may contain a plurality of gas compression cylinders, at least one standard combustion cylinder to drive the compression cylinders, and a common crankshaft in a crankcase coupling the compression cylinders and the at least one standard combustion cylinder. Some combustible gas being compressed may leak past the piston rings of the compression cylinders into the engine crankcase posing a safety concern. This invention eliminates this concern by actively flushing the crankcase at a higher rate than normal.

Systems are provided for a crankcase ventilation system. In one example, a crankcase ventilation (CCV) system for an engine configured to transmit crankcase gases into a clean side air duct, the clean side air duct comprising a sensor and a crankcase ventilation spigot, wherein the crankcase ventilation spigot is configured to be disposed downstream of the sensor, the crankcase ventilation spigot having an outlet configured to direct crankcase gases emerging from the crankcase ventilation spigot away from the sensor.

Systems are provided for a crankcase ventilation system. In one example, a crankcase ventilation (CCV) system for an engine configured to transmit crankcase gases into a clean side air duct, the clean side air duct comprising a sensor and a crankcase ventilation spigot, wherein the crankcase ventilation spigot is configured to be disposed downstream of the sensor, the crankcase ventilation spigot having an outlet configured to direct crankcase gases emerging from the crankcase ventilation spigot away from the sensor.

Various systems and methods are provided for reducing an amount of oil reaching a crankcase overpressure sensor. In one example, a system may include a cast wall protruding perpendicularly from an internal wall of crankcase, the cast wall at least partially surrounding a sensor port for a crankcase overpressure (COP) sensor, the sensor port fluidically coupled to the COP sensor via an internal passage; and a cover plate fixedly coupled to the cast wall, the cover plate parallel to the internal wall. In this way, oil may be blocked from reaching the COP sensor, while air may flow through the internal passage to the COP sensor.

A cable holder for securing a plurality of vehicle engine cables while simulating a vehicle engine distributor comprises a shaft portion and a cap portion provided at a top of the shaft portion. The cap portion cooperates with the shaft portion to define a central passageway therethrough. At least one opening is provided proximate a bottom of the shaft portion and opening to the central passageway, and a plurality of upper apertures are provided proximate a top of the cap portion and opening to the central passageway. A hollow path is formed between the at least one lower aperture and plurality of upper apertures to channel a plurality of vehicle engine cables through the cable holder.

A cable holder for securing a plurality of vehicle engine cables while simulating a vehicle engine distributor comprises a shaft portion and a cap portion provided at a top of the shaft portion. The cap portion cooperates with the shaft portion to define a central passageway therethrough. At least one opening is provided proximate a bottom of the shaft portion and opening to the central passageway, and a plurality of upper apertures are provided proximate a top of the cap portion and opening to the central passageway. A hollow path is formed between the at least one lower aperture and plurality of upper apertures to channel a plurality of vehicle engine cables through the cable holder.

A crankcase breather configured to simulate an ignition system coil is provided that comprises a substantially cylindrical canister having a hollow interior, a first aperture provided proximate a top of the canister and a second aperture provided proximate a bottom of the canister, at least one of the first and second apertures opening to the interior and configured to be connected to a breather hose, and one or more output apertures formed in the canister to release gases received through the breather hose. An exterior of the canister is shaped to resemble an ignition system coil.

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.