Flange Mounted Pumps are ideal for use on diesel engines, fuel oil boosters, gear-reducers or for lubricating oil pumps on engines and compressors. Flange mounted pumps are compact, lightweight and designed to mount directly on the equipment. These pumps are selected when space is limited and an immersed type pump cannot be used. The pumps are mounted directly to the outside of the reservoir solving limited space problems and the direct mounting of these pumps eliminates the need for inlet pipes, shut-off valve and external strainer which can restrict flow and cause vaporization problems. Flange-mounted pumps also eliminate the need for couplings, bases, gears or outboard bearings. In addition, these pumps have an internal safety relief valve and a replaceable casing liner and end discs for easy rebuilding of the pumping chamber if ever necessary.