Remove the retaining ring and press the impeller and bearing off the shaft using a press.
Remove the sealing cuff and thrust sealing ring.
Wash the parts and check their technical condition. The water pump is assembled in the reverse order of removal, taking into account the following:
- press the impeller onto the roller, applying a sealant such as Loctite 270 to the mating surfaces. In this case, it is necessary to maintain the dimension "B" of 1±0.2 mm, shown in the photo. When installing previously used parts, apply a force of approximately 400 kgf when pressing, for new parts it is 500 kgf;
- when installing the hub, maintain the dimension "A" 3±0.5 mm, shown in the photo.
Clean the mating surfaces thoroughly and replace the copper washers.
Further installation of the water pump is performed in the reverse order of removal. Fill with coolant, having first turned the heater control valve switch handle clockwise until it stops.
Start the engine and check for coolant leaks.
[The original article is posted on the resource «BMWMAN»]