The present disclosure relates to a piston for a reciprocating-piston internal combustion engine, comprising a piston head and a piston barrel, wherein the piston head has an encircling ring belt with at least one ring groove for a piston ring and has, in the region of the ring belt, an encircling cooling duct. The cooling duct extends from the ring belt as far as a wall of the piston barrel in order to increase an oil film temperature of the oil film in the cylinder liner between the piston barrel and cylinder and to thereby reduce the piston barrel friction.

A method for operating an active oil separator for separating oil from exhaust air of a crankcase of a motor vehicle with an internal combustion engine. An engine operating state of the internal combustion engine is detected. A first SET rotational speed of the oil separator is determined as a function of the detected engine operating state and a first characteristic map. A maximum SET rotational speed of the oil separator is determined as a function of the first SET rotational speed by the determination device. A preferred SET rotational speed is determined on the basis of the maximum SET rotational speed by a determination device. An electric motor is controlled to drive the oil separator at the preferred SET rotational speed by a control device. A device is also provided for separating oil from exhaust air of a crankcase of a motor vehicle with an internal combustion engine.

An agricultural work vehicle according to an aspect of the invention that can monitor a state of the agricultural work vehicle when the agricultural work vehicle performs agricultural work using a working machine which is attached thereto includes: a vehicle body; a working machine that is attached to the front or rear of the vehicle body and performs agricultural work; an engine that generates a driving force for movement of the vehicle body and work of the working machine; and a monitoring device that determines at least one of whether there is an abnormality in a temperature of a coolant for cooling the engine, whether there is an abnormality in a pressure of an engine oil supplied to the engine, and whether there is an abnormality in the engine when the working machine performs work using the driving force.

The invention relates to a method for controlling the oil pressure of an oil pump (40, 140) in a combustion engine (100). The combustion engine (100) comprises a crankcase (11) and a separator (14, 114) for separating oil present in a blow-by gas from the crankcase (11). The method comprises the step (201) of providing oil pressure demand for a set of different engine operation conditions, the oil pressure demand defining the theoretical required oil pressure of the oil pump (40, 140); the step (203) of controlling the oil pressure of the oil pump (40, 140) based on the oil pressure demand for at least one engine operation condition in the set of different engine operation conditions; the step (205) of driving the separator (14, 114) using oil from the oil pump (40, 140), the oil being pressurized based on the oil pressure demand.

The disclosure relates to a method and a device for checking the functionality of a crankcase ventilation system of an internal combustion engine. The crankcase ventilation system includes two crankcase ventilation lines arranged between a crankcase outlet of a crankcase and an associated introduction point into an air path of the internal combustion engine, via which crankcase ventilation lines gas can be introduced from the crankcase into the air path. The method includes measuring a pressure in the crankcase, supplying the measured pressure values to a control unit, and calculating the gradient of the measured pressure. The method also includes performing a gradient check, checking whether the gradient satisfies a specified criterion, and returning to the measurement of the pressure if the gradient satisfies the specified criterion. The method also includes recording an entry in a fault memory if the gradient does not satisfy the specified criterion.

A method of operating a relief valve assembly for an oil pump includes unblocking a first bypass inlet passage and blocking a first bypass outlet passage, a second bypass inlet passage, and a second bypass outlet passage with a plunger, introducing oil to the relief valve assembly, moving the plunger in a downward direction by a first displacement to unblock the first bypass outlet passage, starting a first bypass of the oil, moving the plunger in the downward direction by a second displacement to block the first bypass inlet passage and unblock the second bypass inlet passage, terminating the first bypass of the oil, moving the plunger in the downward direction by a third displacement to unblock the second bypass outlet passage, and starting a second bypass of the oil.

A method of operating a relief valve assembly for an oil pump includes unblocking a first bypass inlet passage and blocking a first bypass outlet passage, a second bypass inlet passage, and a second bypass outlet passage with a plunger, introducing oil to the relief valve assembly, moving the plunger in a downward direction by a first displacement to unblock the first bypass outlet passage, starting a first bypass of the oil, moving the plunger in the downward direction by a second displacement to block the first bypass inlet passage and unblock the second bypass inlet passage, terminating the first bypass of the oil, moving the plunger in the downward direction by a third displacement to unblock the second bypass outlet passage, and starting a second bypass of the oil.

An arrangement for measuring torque on a camshaft includes a hub extending from a hub first end distal from the camshaft to a hub second end proximal to the camshaft. A barrel extends from a barrel first end distal from the camshaft to a barrel second end and has a barrel bore extending thereinto from the barrel second end such that the hub is received within the barrel bore in a close-sliding interface. The barrel is fixed to the hub at an interface such that relative rotation between the barrel and the hub about the axis is prevented at the interface and the close-sliding interface does not contribute to transmission of torque between the barrel and the hub. A strain gage is located on the barrel between the barrel second end and interface which varies in resistance according to a magnitude of torque transmitted between the barrel and the camshaft.

Methods and systems are provided for diagnosing variable oil pump degradation. In one example, a method may include cranking an engine with a motor and monitoring the motor current draw from a battery during cranking. The method may indicate degradation of a variable oil pump coupled to the engine by comparing the motor current draw with a baseline current level.

An agricultural work vehicle according to an aspect of the invention that can monitor a state of the agricultural work vehicle when the agricultural work vehicle performs agricultural work using a working machine which is attached thereto includes: a vehicle body; a working machine that is attached to the front or rear of the vehicle body and performs agricultural work; an engine that generates a driving force for movement of the vehicle body and work of the working machine; and a monitoring device that determines at least one of whether there is an abnormality in a temperature of a coolant for cooling the engine, whether there is an abnormality in a pressure of an engine oil supplied to the engine, and whether there is an abnormality in the engine when the working machine performs work using the driving force.