Methods and systems are provided for an engine. In one example, a method comprises stopping an engine via a soft-stop method in response to a likelihood of condensate forming being less than or equal to a threshold likelihood. The method further comprises stopping the engine via an exhaust gas evacuation method in response to the likelihood of condensate forming being greater than the threshold likelihood.

A control device predicts whether temporary reduction occurs to a charging efficiency of fresh air in an in-cylinder gas by an influence of an EGR rate of the in-cylinder gas, which increases later than increase of a charging efficiency of the in-cylinder gas, if a first arithmetic operation is applied to calculating a target throttle opening degree based on a target charging efficiency which is increasing, in a case of shifting to an acceleration operation, by using a prediction model expressing dynamic characteristics of an internal combustion engine. When it is predicted that temporary reduction occurs to the charging efficiency of the fresh air, the control device calculates the target throttle opening degree by a second arithmetic operation by which an increase speed of a throttle opening degree is restrained more than by the first arithmetic operation, instead of calculating the target throttle opening degree by the first arithmetic operation.

A controller may identify an indication to initiate an engine braking procedure associated with an engine of a machine. The controller may obtain, based on identifying the indication to initiate the engine braking procedure, information relating to a requested amount of engine braking power of the engine. The controller may cause one or more components of a variable geometry turbocharger (VGT) of the engine to adjust, and a throttle valve of the engine to adjust, based on the information relating to the requested amount of engine braking power of the engine.

A controller may identify an indication to initiate an engine braking procedure associated with an engine of a machine. The controller may obtain, based on identifying the indication to initiate the engine braking procedure, information relating to a requested amount of engine braking power of the engine. The controller may cause one or more components of a variable geometry turbocharger (VGT) of the engine to adjust, and a throttle valve of the engine to adjust, based on the information relating to the requested amount of engine braking power of the engine.

A general purpose engine includes: a cooling fan fixed to an engine rotary shaft; a muffler to silence exhaust gases; a muffler covering to cover the muffler; and an auto choke device to control an opening of a choke valve in an air intake passage by the utilization of heat evolved from the muffler. The auto choke device includes: a drive source, which is fitted to the muffler covering in a non-contact fashion to the muffler and exposed to an outer surface of the muffler covering; and a link member to connect between the drive source and the choke valve. The drive source includes a bracket, which is fitted to the muffler covering, and a bimetal fitted inside the bracket. The bracket includes a heat shield extending towards an inner side of the muffler covering, and the heat shield blocks out a cooling wind then flowing towards the bimetal.

A method is provided for controlling an internal combustion engine including at least one first cylinder and at least one second cylinder with respective reciprocating pistons, each of the first and second cylinders being arranged to receive air from a fresh air intake arrangement, to receive fuel, and to provide repetitive combustions by means of the received air and fuel, the method including receiving in the first cylinder air from the fresh air intake arrangement, expelling from the first cylinder gases in the form of the air received in the first cylinder or gases including at least a portion of the air received in the first cylinder, guiding to the second cylinder gases expelled from the first cylinder, injecting fuel into the second cylinder so as to provide repetitive combustions with air in the gases guided from the first cylinder to the second cylinder, and, while guiding to the second cylinder gases expelled from the first cylinder, throttling or inhibiting the supply to the second cylinder of air from the fresh air intake arrangement, wherein guiding to the second cylinder gases expelled from the first cylinder includes guiding to the second cylinder all gases expelled from the first cylinder.

An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

Methods and systems are provided for an engine. In one example, a method comprises stopping an engine via a soft-stop method in response to a likelihood of condensate forming being less than or equal to a threshold likelihood. The method further comprises stopping the engine via an exhaust gas evacuation method in response to the likelihood of condensate forming being greater than the threshold likelihood.

A method is provided for controlling an internal combustion engine including at least one first cylinder and at least one second cylinder with respective reciprocating pistons, each of the first and second cylinders being arranged to receive air from a fresh air intake arrangement, to receive fuel, and to provide repetitive combustions by means of the received air and fuel, the method including receiving in the first cylinder air from the fresh air intake arrangement, expelling from the first cylinder gases in the form of the air received in the first cylinder or gases including at least a portion of the air received in the first cylinder, guiding to the second cylinder gases expelled from the first cylinder, injecting fuel into the second cylinder so as to provide repetitive combustions with air in the gases guided from the first cylinder to the second cylinder, and, while guiding to the second cylinder gases expelled from the first cylinder, throttling or inhibiting the supply to the second cylinder of air from the fresh air intake arrangement, wherein guiding to the second cylinder gases expelled from the first cylinder includes guiding to the second cylinder all gases expelled from the first cylinder.