Abstract: A combination for an opposed-piston engine includes an intake piston and an exhaust piston, each with a top land height. The intake piston top land height is less than the exhaust piston top land height.

Abstract: Pistons for opposed-piston engines include an interior annular cooling gallery. The gallery is provided with inlet and drain passageways constructed to shield a jet of liquid coolant entering the gallery, thereby reducing interference between the incoming jet and liquid coolant circulating in the gallery.

Abstract: A connecting rod assembly has a connecting rod with a large end and a small end, a piston wrist pin, and fasteners to connect the connecting rod to the piston wrist pin and optionally one or more shims in between the connecting rod and piston wrist pin. A notch on the wrist pin allows for the seating of a flat surface on the small end of the connecting rod in the connecting rod assembly. Side walls on both the notch and the small end of the connecting rod limit twist. The connecting rod assembly allows for the adjustment of piston location in a cylinder while limiting connecting rod twist.

Abstract: An opposed-piston engine is configured to fit in an engine compartment of a light-duty truck without compromising engine operations or the integrity of the engine compartment. The opposed-piston engine includes an air handling system and can be configured so that a cylinder assembly of the engine is tilted. The tilt of the cylinder assembly can allow for all of the components of the engine's air handling system to be located on one side of the opposed-piston engine. The air handling system of the opposed-piston engine can be configured with a cobra-head shaped intake duct assembly.

Abstract: A main bearing cap construction far a dual-crankshaft, opposed-piston engine has two sets of bolts in a cross-bolted configuration. In a dual-crankshaft opposed-piston engine with at least four main bearings, at least one of the main bearings will have a cap with two sets of bolts in a cross-bolted configuration. In addition to having a cross-bolted configuration, the main bearing cap configuration can have flanges to receive blind bolts and/or additional surface area to interface with the cylinder block.

Abstract: In an opposed-piston engine which includes a catalytic aftertreatment device in its exhaust system an exhaust gas condition indicating a catalyst temperature of the aftertreatment device is monitored. When the catalyst temperature is near or below a light-off temperature, a catalyst light-off procedure is executed to elevate the temperature of the catalyst.

Abstract: Control of fuel flow in a uniflow-scavenged, two-stroke cycle, opposed-piston engine includes limiting an amount of torque or fuel in response to a torque demand, based upon a comparison and a selection of fuel delivery options derived from a global airflow parameter and/or a trapped airflow parameter.

Abstract: A piston for an opposed-piston, internal combustion engine includes a crown with an end surface having a bowl shaped to form a combustion chamber with an end surface of an opposing piston in the opposed-piston engine. A substantially circumferential top land of the crown meets the end surface at a substantially circular peripheral edge, and a skirt comprising a sidewall extends from a substantially circumferential belt region of the crown. A wristpin bore with a wristpin axis opens through the sidewall. The end surface of the piston includes a pair of injection regions across which fuel is injected into the bowl. The injection regions are disposed in substantially diametrically-opposed quadrants of the end surface which are defined by the wristpin axis and a connecting rod envelope axis substantially orthogonal to the wristpin axis. Each injection region extends along a respective arc concentric with the substantially circular peripheral edge.

Abstract: An exhaust plenum chamber with a thermal barrier coating for an opposed-piston engine reduces heat rejection to coolant, while increasing exhaust temperatures, fuel efficiency, and quicker exhaust after-treatment light-off. The exhaust plenum chamber can include a coating on the inside surface of the chamber. Posts which are structural and provide cooling channels or passageways can be present in the exhaust plenum chamber and coated with the thermal barrier coating material.

Abstract: An air handling arrangement in a two-stroke cycle, opposed-piston engine with uniflow scavenging and constructed for heavy-duty operation includes sequentially arranged turbochargers in series with a supercharger. In some aspects, the air handling system is equipped with an EGR channel.

Abstract: A cylinder liner for an opposed-piston engine, and corresponding methods of extending engine durability and thermal management therewith, has opposite ends and a bore with a longitudinal axis for supporting reciprocating movement of a pair of opposed pistons. An intermediate portion of the liner extends between the opposite ends and includes an annular liner portion within which the pistons reach respective TC locations. A liner ring is seated in a portion of the bore in the annular liner portion, between the TC locations, for scraping carbon from top lands of the pistons and/or increasing the thermal resistance of the annular liner portion.

Abstract: An exhaust manifold assembly with a thermal barrier coating for an opposed-piston engine reduces heat rejection to coolant, while increasing exhaust temperatures, fuel efficiency, and quicker exhaust after-treatment light-off. The exhaust manifold assembly can include a coating on the inside surface of the manifold assembly. The coated exhaust manifold assembly can ensure structural robustness of the exhaust manifold assembly over a larger range of operating temperatures.

Abstract: A method of operating a two-stroke cycle, opposed-piston engine comprising a pumping device coupled to pump air to cylinders of the engine through a charge air cooler and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders by which a thermal state of the exhaust sufficient to sustain thermal activation of one or more of the aftertreatment system devices may be maintained during a deceleration or motoring condition of operation by reducing the mass airflow to the engine.

Abstract: A supercharger assembly includes rotors, a base plate, and a housing with an anti-fouling material on one or more surfaces where accumulation of soot and/or soot-like material may lead to mechanical friction and possibly seizing. The anti-fouling material can have oleophobic and/or hydrophobic properties.

Abstract: A parent bore cylinder block of an internal combustion, opposed-piston engine includes cooling passages that are formed using a 3-D printed casting core. The casting core can include portions that are ceramic. The parent bore cylinder block can include multiple cylinders, each cylinder with cooling passages and turbulence inducing features in those cooling passages, particularly surrounding the central portions of the cylinders.

Abstract: A piston crown for a piston of a pair of pistons in a two-stroke, opposed-piston, compression ignition combustion engine has a barrier layer and a conductive layer. The barrier layer at least partially surrounds a combustion chamber formed by the piston crown and an end surface of an opposing piston. The conductive layer connects the crown to the rest of the piston body. The barrier layer and the conductive layer are joined either through welding or through the fabrication process. Optionally, the piston crown includes an insulating layer between the barrier and conductive layers.

Abstract: In an air handling system of an opposed-piston engine, mass airflow sensor operation is monitored by comparing mass airflow measured by the sensor with mass airflow through a supercharger.

Abstract: In a supercharged, two-stroke cycle, opposed-piston engine with an EGR loop, exhaust gas recirculated to a charge air channel through which charge air is provided to a supercharger inlet is cleansed of particulate materials by a particulate filter located in the EGR channel to capture and oxidize particulate matter before EGR is allowed to flow through the supercharger and any cooler in the EGR flow path. A diesel oxidation catalyst device may be provided in the EGR channel, in series with the particulate filter.

Abstract: An opposed-piston engine includes at least two of: a gear train with a backlash reducing means; a viscous damper; and a centrifugal pendulum absorber. The opposed-piston engine can include two crankshafts and a gear train to connect the crankshafts. Any viscous dampers and centrifugal pendulum absorbers can be used to mitigate torsional velocity fluctuations in crankshafts in the engine, and multiple viscous dampers and/or centrifugal pendulum absorbers can be used in an engine. The backlash reducing means can include any of a means to adjust the position of gears in a gear train relative to each other and one or more backlash reducing gears.

Abstract: A transmission for an opposed-piston engine with two crankshafts includes a crankshaft gear train that combines the torque inputs from the two crankshafts and a gear arrangement coupled to the gear train that is operable to obtain various speed ratios for an output torque drive.