An assembly for an aircraft turbine engine, the assembly comprising a reduction gear for driving the fan of the turbine engine, as well as a lubrication system including: - a reduction gear enclosure, lubricated and containing the fan drive reduction gear; - a lubricant tank; - a lubricant supply circuit connecting the tank to the reduction gear enclosure, the supply circuit comprising a lubricant supply pump; - a lubricant recovery circuit connecting the reduction gear enclosure to the tank, the recovery circuit comprising a pump for recovering lubricant from the reduction gear enclosure, characterised in that the lubricant recovery circuit includes a controlled lubricant dispenser, comprising: - a lubricant inlet communicating with a lubricant outlet of the reduction gear enclosure; - an air inlet; and - a dispenser outlet communicating with the recovery pump, the controlled lubricant dispenser being configured so as to be able to adopt several configurations, among which: - a lubricant recovery configuration, in which the dispenser communicates the lubricant inlet thereof with the outlet thereof, and prohibits the communication between the air inlet thereof and the outlet thereof; and - a configuration for blocking the lubricant in the enclosure, a configuration in which the dispenser communicates the air inlet thereof with the outlet thereof, and prohibits the communication between the lubricant inlet thereof and the output thereof. - a reduction gear enclosure, lubricated and containing the fan drive reduction gear; - a lubricant tank; - a lubricant supply circuit connecting the tank to the reduction gear enclosure, the supply circuit comprising a lubricant supply pump; - a lubricant recovery circuit connecting the reduction gear enclosure to the tank, the recovery circuit comprising a pump for recovering lubricant from the reduction gear enclosure, characterised in that the lubricant recovery circuit includes a controlled lubricant dispenser, comprising: - a lubricant inlet communicating with a lubricant outlet of the reduction gear enclosure; - an air inlet; and - a dispenser outlet communicating with the recovery pump, - a lubricant inlet communicating with a lubricant outlet of the reduction gear enclosure; - an air inlet; and - a dispenser outlet communicating with the recovery pump, the controlled lubricant dispenser being configured so as to be able to adopt several configurations, among which: - a lubricant recovery configuration, in which the dispenser communicates the lubricant inlet thereof with the outlet thereof, and prohibits the communication between the air inlet thereof and the outlet thereof; and - a configuration for blocking the lubricant in the enclosure, a configuration in which the dispenser communicates the air inlet thereof with the outlet thereof, and prohibits the communication between the lubricant inlet thereof and the output thereof. - a lubricant recovery configuration, in which the dispenser communicates the lubricant inlet thereof with the outlet thereof, and prohibits the communication between the air inlet thereof and the outlet thereof; and - a configuration for blocking the lubricant in the enclosure, a configuration in which the dispenser communicates the air inlet thereof with the outlet thereof, and prohibits the communication between the lubricant inlet thereof and the output thereof.