An adjustable lubrication oil conveying system for a combustion engine is proposed which comprises a screw pump for conveying lubrication oil with at least one screw rotatably accommodated in a screw chamber, wherein the screw pump is arranged such that a suction side of the screw chamber is connected with an intake path from an oil sump of the combustion engine, and a pressure side of the screw chamber is connected with a feed path to moving parts of the combustion engine. The lubrication oil conveying system is characterised in particular in that the screw pump is driven by the combustion engine; and towards the suction side of the screw chamber, an adjustable throttle valve is provided by means of which a flow cross-section of the intake path is gradually limitable between an opened position and a closed position. Therefore, the oil pressure in a combustion engine is, for the first time, adjusted by suction throttling in connection with a screw pump.