The 00642239 is a genuine OEM dishwasher drain pump assembly designed for Bosch, Thermador, Gaggenau, and Kenmore Elite dishwashers. This critical component removes used water from the dishwasher tub at the end of each wash and rinse cycle, pumping it through the drain hose to your home's drain system. The drain pump is essential for proper dishwasher operation—without a functioning drain pump, water remains standing in the bottom of the tub, preventing the dishwasher from completing cycles, causing odors, and making the dishwasher completely unusable. The drain pump operates during the drain phase of each cycle, typically running for 1-3 minutes to evacuate all water from the tub and sump area before the next cycle phase begins. The 00642239 features a high-efficiency 9-vane impeller design that provides superior water evacuation performance, handles food debris and particles without clogging, and operates quietly compared to older pump designs. The drain pump is constructed from premium materials including a powerful 120V AC electric motor (0.6 amp draw, 72 watts power consumption, rated for continuous duty operation), durable 9-vane centrifugal impeller (thermoplastic construction, designed to handle food particles up to 1/4 inch, self-cleaning design prevents clogging), corrosion-resistant pump housing (sealed construction prevents leaks, designed for hot water and detergent exposure), two male electrical terminals with spade connectors (quick-connect design for easy installation), inlet and outlet ports with hose barb connections (secure hose attachment, prevents leaks), integrated mounting bracket with screw holes (secures pump to dishwasher base), and sealed motor bearings (maintenance-free, designed for 10+ year lifespan). The pump measures approximately 5.5 inches in length, 4.5 inches in width, and 5 inches in height, with a weight of approximately 1.5 pounds. The 00642239 replaces older part numbers including 642239, AP3996662, PS8729769, 1387293, 00184178, 9000200446 and features improved motor design for longer life and quieter operation (30% quieter than previous generation), enhanced impeller design for better debris handling and reduced clogging, upgraded seals for better leak prevention, improved electrical connections for reliability, and optimized pump efficiency for faster drainage and lower energy consumption. The dishwasher drain pump operates through electric motor-driven centrifugal force and fluid dynamics: during the drain phase, the control board sends 120V AC power to the drain pump motor through the wiring harness; the motor spins the impeller at high speed (typically 2800-3200 RPM); centrifugal force from the spinning impeller creates low pressure at the center (inlet) and high pressure at the outer edge (outlet); water is drawn from the dishwasher tub through the sump and into the pump inlet; the impeller accelerates the water and forces it out through the pump outlet under pressure; the pressurized water flows through the drain hose to your home's drain system (standpipe, garbage disposal, or air gap); the pump continues running until the water level sensor or timer signals the control board that the tub is empty; the control board cuts power to the pump motor and the cycle advances to the next phase. The pump is designed to handle hot water (up to 160°F), detergent solutions, food particles, and continuous operation without overheating or failure. Common failure causes include normal wear from age and continuous operation (typical pump lifespan 8-12 years with average use, 3000-5000 wash cycles), motor bearing failure from wear causing grinding noise and eventual seizure, impeller damage from hard objects (bones, fruit pits, glass fragments) jamming the pump, seal failure causing water leaks from the pump housing, motor winding failure from electrical issues or overheating, clogging from excessive food debris or foreign objects preventing impeller rotation, electrical connection corrosion from moisture exposure, or manufacturing defects. When the drain pump fails, symptoms include dishwasher not draining (water standing in bottom of tub after cycle), slow drainage (takes longer than 2-3 minutes to drain), loud grinding, humming, or buzzing noise during drain cycle (motor running but impeller jammed or bearing failed), water leaking from bottom of dishwasher (pump seal failure), error codes on display (E24, E25 drain fault codes on Bosch models), dishwasher stopping mid-cycle with water in tub, or complete pump failure (no sound during drain cycle, motor won't run). The 00642239 is a complete pump assembly that includes the motor, impeller, housing, and all necessary connections, providing a comprehensive solution for dishwasher drainage problems. IMPORTANT: This is a 9-vane impeller design rated for 120V operation—verify your dishwasher requires this specific pump before ordering. Some models use different pump configurations. CRITICAL: Always disconnect power and water supply before working on the dishwasher to prevent electrical shock and water damage. This is a moderate repair requiring removal of the dishwasher kickplate and access panel to reach the pump in the base of the unit.