GRAF WATER PUMP w/METAL IMPELLER + O-RING BMW: 320i 1992-1995; 2001-2005; 323Ci 2000; 323i 1998-2000; 323is 1998-1999; 325Ci 2001-2006; 325i 1992-1995, 2001-2005; 325is 1992-1995; 325xi 2001-2005; 328Ci 2000, 328i 1996-2000; 328is 1996-1999; 330Ci 2001-2006; 330i 2001-2005; 330xi 2001-2005; 525i 1991-1995, 2001-2005; 525iT 1993; 528i 1997-2000; 530i 2001-2005; M3 1994-1999; X3 2004-2006; X5 2001-2006; Z3 1997-2002; Z4 2003-2005 Please be sure your vehicle is listed in the compatibility chart. We are not responsible for fitment. Sold with a 2 year warning. Graf Water Pump The Graf Water Pump contains no remanufactured parts and is produced using an optimized all metal impeller design to assist in cooling under high RPM, and performance demands. Selection of raw materials, reliability of machinery and production processes, stringent controls throughout the production process, from melting to fitting, as well as reliability tests performed using equipment able to determine true performance, go to ensure this product is a real guarantee of safety and long life. The Graf water pump is centrifugal in type and comprises a bladed rotor linked by means of a shaft (which rotates on bearings housed in a support) to the drive gear; the seal between the pump and the motor block is guaranteed by a gasket, while the inside of the pump is guaranteed by a mechanical seal. Component parts: Impeller: supplies the fluid with the necessary energy to cover the entire cooling circuit. Mechanical seal: ensures fluid seal inside the pump. Bearing: transmits movement to the impeller and supports any ventilation parts. Entrainment part: for transmitting movement to the bearing. Pump body: supports the basic pump component parts and conveys the coolant in the motor block. Features and Benefits: All the component parts fitted are pre-tested to evaluate durability, performance and reliability. The bearings undergo a durability test equivalent to nominal lifespan and are then inspected to assess integrity. The mechanical seals are tested in extreme coolant temperature conditions according to predefined cycles. The shape of the impellers is optimized thanks to the use of prototypes on which flow and performance tests are performed. On both the entrainment parts and the bodies, the choice of materials and/or technologies different to original ones is made on the basis of structural and mechanical tests. After assembly all the pumps undergo seal tests on units that reject those with leaks above set limits.