BMW Electric Water Pump Failure – How, Why, and What To Prevent

What This BMW 540 has was diagnosed with a defective engine coolant pump. Symptoms were overheating and damaged drive belt system. Disassembly of the front cover and removal of the water pump allowed for inspection of the pump. How The mode of failure with this pump appears to be simple age and miles, likely exasperated by a lack of coolant changes. The bearing failed on the pump, allowing the plastic impeller to contact the aluminum housing, you can see the growing on the surface. Finally the plastic impeller itself failed, the vehicle overheated, and came to a stop. As the water pump [...]

By | July 18th, 2018|Case Studies|Comments Off on BMW Electric Water Pump Failure – How, Why, and What To Prevent

2008 BMW 335XI – Electric Water Pump Replacement

Most cars, including older BMWs, use a water pump which is driven by a belt on the front of the engine, a tried and proven design, but not one which allows dynamic control. As it has transitioned from the older "M" engine to the new "N" designs, BMW has come up with an interesting twist, an electric engine coolant/water pump. An electric water pump is really a brilliant idea, it offers a higher level of control of the engine operating parameters. The electric pump can be turned on and off as needed to speed up engine warm up time and [...]

By | August 19th, 2011|Case Studies|Comments Off on 2008 BMW 335XI – Electric Water Pump Replacement

Audi TT Quattro 1.8 Turbo – Defective Water Pump

This car has was diagnosed with a defective engine coolant pump. Symptoms were overheating and noise from the front timing belt area. Disassembly of the front cover and timing belt, no easy task on at Audi TT, allowed for removal and inspection of the pump. As you can see from the photos, it is a bit of a process to access the pump, so be sure to always replace the timing belt and tensioner at the same time. The timing belt, scheduled by Audi for replacement at 105K miles, has a history of failing considerably sooner, so consider timing belt [...]

By | July 21st, 2011|Case Studies|Comments Off on Audi TT Quattro 1.8 Turbo – Defective Water Pump

Audi S6 – Timing Belt Service w/ Water Pump

The Audi S6 timing belt service does not normally require removal of the nose of the car, but in this case the silicone filled fan clutch was seized onto the idler shaft and could not be removed with the nose in place. 10 years and more recently time in the coastal environment seemed to have done its worse. To fully access the clutch required removal of the front bumper cover, radiator support and radiator, evacuate and recharge of the A/C system. As the engine water pump is driven off the camshaft belt, it is a good idea to replace the [...]

By | July 18th, 2011|Case Studies|Comments Off on Audi S6 – Timing Belt Service w/ Water Pump

Audi A8 – Head Gasket Service

Timing belt replacement on the Audi A8 requires a fair amount of disassembly on the front end of the vehicle. The Audi 4, 6 and 8 cylinder engines are high compression types, failure of the timing belt will result in major engine damage. Although scheduled by Audi for 90,000 miles, we have found loose or severely worn timing belts and tensioners at the 75K mile mark. When replacing the rubber timing belt, all belt rollers, water pump and thermostat must be replaced. This is a service you only want to do every 100,000 miles. We have noted a number of [...]

By | July 17th, 2011|Case Studies|Comments Off on Audi A8 – Head Gasket Service