An engine includes: an exhaust manifold 7 close to one of left and right side surfaces of an engine; a turbocharger 60 having an exhaust-side inlet connected to the exhaust manifold 7; and a rocker-arm-chamber-integrated intake manifold 8 being disposed on an upper surface of a cylinder head 5 and integrally including a rocker arm chamber 90 and an intake manifold 6. The intake manifold 8 has a wall 101 dividing the rocker arm chamber 90 close to the one of the left and right side surfaces of the engine 1 and the intake manifold 6 close to the other of the left and right side surfaces to isolate the rocker arm chamber 90 and the intake manifold 6 from each other. The rocker arm chamber 90 has, in its upper portion, a positive crankcase ventilation device 69 protruding therefrom and being configured to return blowby gas to an intake system. The positive crankcase ventilation device 69 has, in its side surface, a blowby-gas discharge port 67 connected with a gas conduit 68 through which blowby gas is delivered to an intake-side inlet of the turbocharger 60.

An engine includes: an exhaust manifold 7 close to one of left and right side surfaces of an engine; a turbocharger 60 having an exhaust-side inlet connected to the exhaust manifold 7; and a rocker-arm-chamber-integrated intake manifold 8 being disposed on an upper surface of a cylinder head 5 and integrally including a rocker arm chamber 90 and an intake manifold 6. The intake manifold 8 has a wall 101 dividing the rocker arm chamber 90 close to the one of the left and right side surfaces of the engine 1 and the intake manifold 6 close to the other of the left and right side surfaces to isolate the rocker arm chamber 90 and the intake manifold 6 from each other. The rocker arm chamber 90 has, in its upper portion, a positive crankcase ventilation device 69 protruding therefrom and being configured to return blowby gas to an intake system. The positive crankcase ventilation device 69 has, in its side surface, a blowby-gas discharge port 67 connected with a gas conduit 68 through which blowby gas is delivered to an intake-side inlet of the turbocharger 60.

An apparatus that improves the gas mileage of an internal combustion engine in a vehicle is disclosed that is comprised of an air inlet, a condensation chamber, and an air outlet that is connected to the vehicle's oil system through an oil filler port in the engine of the vehicle.

A blowby gas treatment device includes a pressure control valve, a fresh air induction pipe, a first blowby gas pipe, a second blowby gas pipe, a shutoff valve, a one-way valve, and a PCV valve. A leak diagnosis includes a first-stage diagnosis to determine whether or not falling of a pressure in a crank case after closing of the shutoff valve under a non-supercharging condition is normal. A second-stage diagnosis is implemented by moving the pressure control valve from a fully opened state into a fully closed state, and determining whether an intake air quantity in each state is equal to each other. When the intake air quantity in each state is equal to each other, presence of an in-system leak is determined. When a fully closed state intake air quantity is different from a fully opened state intake air quantity, presence of an out-of-system leak is determined.

An engine control device is provided, which includes a blowby gas passage connecting an engine body to an intake passage so that blowby gas leaked from a combustion chamber is recirculated to the intake passage, a boost pressure changer configured to change a boost pressure of a turbocharger, and a controller configured to set a target boost pressure and control the boost pressure changer. The turbocharger includes a turbine which is provided to an exhaust passage and driven by exhaust gas, and a compressor which is provided to the intake passage and rotary driven by the turbine to boost intake air. The blowby gas passage is connected to the intake passage near the compressor. The controller corrects the target boost pressure when an ambient temperature is below a given determination temperature, to be higher than the target boost pressure when the ambient temperature is at or above the determination temperature.

A prime mover includes an engine, a fan to generate a cooling airflow around the engine, an air-intake tube to supply outside air to the engine, a connection tube to supply, to the air-intake tube, a blow-by gas generated in the engine, and a wind shielding member to shield the connection tube from the cooling airflow, the wind shielding member being arranged around the connection tube.

A prime mover includes an engine, a fan to generate a cooling airflow around the engine, an air-intake tube to supply outside air to the engine, a connection tube to supply, to the air-intake tube, a blow-by gas generated in the engine, and a wind shielding member to shield the connection tube from the cooling airflow, the wind shielding member being arranged around the connection tube.

Systems, devices and methods for diagnosing malfunctioning in a crankcase ventilation (CCV) system can include a controller receiving a plurality of pressure values. The plurality of pressure values include a first pressure value indicative of pressure of gases flowing between a crankcase and a breather assembly, a second pressure value indicative of pressure of gases flowing through a CCV tube from the breather assembly, and a third pressure value representing pressure of gases in a tube connected to the CCV tube. The controller can calculate a pair of pressure differences including a first pressure difference between the first pressure value and the second pressure value and a second pressure difference between the first pressure value and the third pressure value. The controller can detect a malfunctioning or defect in the CCV system based on the pair of pressure differences falling within a predefined clustering region.

In a combustion engine, an exit stream of blow-by gases follows a fluid pathway through an oil and air separator and a breather filter, the oil and air separator including a first housing including a central chamber therein, the central chamber divided into a first outer portion and a second inner portion by a barrier; a filter material disposed between the first outer portion and the second inner portion; a cap directly coupled to the first housing, the cap including a first lumen therethrough, the first lumen including a first end disposed at the second inner portion; and a coupler removably coupling the cap and an extension portion including a second lumen therethrough.

The ventilator-equipped engine is configured to: guide a blow-by gas generated in a crankcase to an intake passage through an inside of a cylinder head, an inside of a head cover, and a pressure regulating valve; and to directly introduce fresh air into an internal space of the cylinder head by providing a fresh air introduction passage that extends across the intake passage and the cylinder head.