Quote:
Originally Posted by Efthreeoh
The BMW electric water pump should last the life of the car, there is nothing to cause it to fail other than heat.
Heat should be better taken into consideration of the design of the pump. IMO whoever designed the pump (BMW or the OEM supplier) did a poor job at managing the heat load the pump sees during its life. My pump failed at 150,000 miles because the control electronics overheated on a 100+ degree day in July. Someone posted pictures in the Forum of his dissected pump where the motor armature delaminated. Electric motors have been around for over 100 years and are used in service locations where they run for thousands and thousands of hours in much harsher environments than pushing a few gallons of 230 degree coolant around an engine cooling system.
But if the BMW waterpump has a design life of so many miles as a compromise on energy use, weight, or cost factors then fine, just tell us the mean time between failure of the pump and recommend a replacement interval. Or at least give us a water temperature gauge and a better early warning system when it starts to fail. The ECU keeps codes on when the pump starts to fail. There is no reason BMW could not incorporate the codes into a notification of the event so the owner can preemptively replace the pump and avoid a breakdown.
And $500 for a replacement pump is a bit ridiculous; for that kind of price I would expect the pump to be a robust piece that SHOULD last the life of the car. The only bebefit I see to the BMW use of an electric waterpump is the Rest-heat function, and faster warmup of the engine.
Major fail by BMW.
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So true for the part in bold. I wonder if another carmaker uses electric waterpumps? Another "benefit" is also the control of the temperature according to context. On highways, the engine runs hotter (215-230) while in city, it is colder (175-190). But frankly, the results are not spectacular.
That was not a brilliant idea to put electronic on a boiling circuitry.