An additional water pump is an electric coolant pump that works independently of the engine speed. Where the mechanical water pump moves little coolant at idle, the additional pump keeps the coolant flowing through the cabin heater, so the heater blows warm in traffic; on turbocharged engines it runs on after the engine has been switched off and carries the heat out of the turbocharger housing; on engines with stop-start and on hybrid cars it keeps the coolant moving while the engine is stopped. It is switched by the engine control unit and sits in a hose run, in the engine bay or under the car.
Additional pumps fail electrically and mechanically. The motor wears its brushes or its bearing and seizes, so the pump draws current without turning; the winding fails open and the control unit logs a fault; the housing cracks or the seal between the motor and the pump chamber leaks coolant into the motor. The symptoms are a heater that is cold at idle and warm on the move, a fault code for the pump circuit, a coolant leak at the pump, and on turbocharged engines a turbocharger that runs its bearing hot.
MONTTRON additional water pumps are made to OEM-compliant quality and as aftermarket spare parts: the delivery, the hose connections, the connector and the mounting of the original, so the pump fits the original hoses and bracket and answers the original control unit. The materials are tested for durability and temperature resistance.
The range covers European and Japanese passenger cars. Each reference is identified by the OE number of the original part; send that number and the vehicle identification number (VIN) and we confirm the matching MONTTRON reference.
For availability and OE cross-references, contact us by email.