A standby generator includes an engine including an output shaft, an alternator, and an enclosure including a base and a number of walls extending from the base including a front wall, a rear wall, a left wall, and a right wall. The output shaft extends toward the alternator and the left wall. The standby generator includes an intake opening configured to allow air to be drawn into the enclosure and an exhaust opening configured to allow heated air and exhaust gases to be expelled from the enclosure. The intake opening is provided on the rear wall and the exhaust opening is provided on the front wall.

A standby generator includes an engine, an alternator, and an enclosure including a base and a number of walls extending from the base including a front wall, a rear wall, a left wall, and a right wall. The standby generator includes an intake opening configured to allow air to be drawn into the enclosure and an exhaust opening configured to allow heated air and exhaust gases to be expelled from the enclosure. The intake opening is provided on the rear wall and the exhaust opening is provided on the front wall.

An engine may include a cylinder having a first combustion chamber at one end thereof and a second combustion chamber at an opposing end thereof, first and second cylinder heads at an end of the first combustion chamber and the second combustion chamber, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in a first stroke from the first end to the second end of the cylinder. The piston and the cylinder may be configured such that the first stroke includes an expansion stroke portion during which chemical energy from combustion in the first combustion chamber is converted into mechanical power of the piston, and a momentum stroke portion during which the piston continues to move to the second end of the cylinder and gases are exchanged between the first combustion chamber and a location outside the cylinder.

The oil filter device is disposed on a side portion of one side of a cylinder body in a width direction in a cylinder head side with respect to an engine case in a space between center lines of main lubricating oil passages and a cylinder axis line of the cylinder body, and includes an oil pump disposed on the engine case and further lubricating oil passages that connect to the main lubricating oil passage.

An engine case includes bearings, an oil pump, lubricating oil passages, and a relief device. The bearings rotatably support a crankshaft and a camshaft. The oil pump and the lubricating oil passages are configured to pressure-feed lubricating oil to the bearings. The relief device is configured to adjust a pressure of the lubricating oil. The lubricating oil passages include main lubricating oil passages. The main lubricating oil passages include communication portions linearly formed with extending portions. The communication portions communicate between the respective bearings of the crankshaft and the camshaft from outside the engine case. The extending portions extend from outside the engine case to the bearing of the camshaft. The relief device is disposed having a relief valve and a relief hole at the extending portions.

An opposed-piston engine has a cylinder block with a plurality of cylinders arranged inline, with each cylinder including an intake port longitudinally separated from an exhaust port. The engine is equipped with an air handling system that includes intake and exhaust chambers inside the cylinder block. All of the cylinder intake ports are contained in the intake chamber to receive charge air therein. The intake chamber includes elongated air inlets opening through opposing sides of the cylinder block. The exhaust chamber includes at least one exhaust outlet opening through a side of the cylinder block; all of the cylinder exhaust ports are contained in the exhaust chamber to discharge exhaust thereinto.

An opposed-piston engine has a cylinder block with a plurality of cylinders arranged inline, with each cylinder including an intake port longitudinally separated from an exhaust port. The engine's air handling system includes open intake and exhaust chambers in the cylinder block. The open chamber constructions eliminate the need for multi-pipe manifolds and smooth the flow of charge air.

An internal combustion engine may include an engine block, a cylinder defining a combustion chamber, and a piston in the cylinder. The piston may travel in a first stroke from one end to an opposite end of the cylinder, and may be sized relative to the cylinder to enable an expansion stroke portion of the first stroke while the piston travels under gas expansion pressure, and a momentum stroke portion of the first stroke for the remainder of the first stroke following the expansion stroke portion. A piston rod portion may be connected to the piston and extend from a location within the combustion chamber to an area external to the cylinder. A recess in the piston rod portion may form a passageway to continuously communicate gas flow between the combustion chamber and the area external to the cylinder when the piston is in the momentum stroke portion.

An internal combustion engine may include an engine block, a cylinder defining a combustion chamber, and a piston in the cylinder. The piston may travel in a first stroke from one end to an opposite end of the cylinder, and may be sized relative to the cylinder to enable an expansion stroke portion of the first stroke while the piston travels under gas expansion pressure, and a momentum stroke portion of the first stroke for the remainder of the first stroke following the expansion stroke portion. A piston rod portion may be connected to the piston and extend from a location within the combustion chamber to an area external to the cylinder. A recess in the piston rod portion may form a passageway to continuously communicate gas flow between the combustion chamber and the area external to the cylinder when the piston is in the momentum stroke portion.

A linear reciprocating engine may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The engine may further include a first piston rod portion extending from a first face of the double-faced piston through the first combustion chamber, and a second piston rod portion extending from a second face of the piston through the second combustion chamber. Passageways in the piston rod portions may be configured to communicate gases between the combustion chamber and a location outside the cylinder and configured to prevent gases from being exchanged between the cylinder and a location outside the cylinder via a path that crosses both face of the piston.