Abstract: In an engine assembly a fuel reservoir is located at a relatively high position, a fuel pump at a relatively low position, and a fuel strainer between the two. The strainer is fitted with a three-way cock, which in turn is connected by an inclined conduit to the fuel reservoir. In one position, the cock is closed. In the other two positions, it connects with either the unfiltered-fuel chamber or the filtered-fuel chamber of the fuel strainer, to drain air from the connected chamber into the fuel reservoir. With the arrangement, fuel entrained in escaping air is captured, and now allowed to enter the atmosphere.