How to Replace the Water Pump on a 1998 BMW

The water pump is the heart of your engine's cooling system, circulating the coolant throughout the engine. When the bearing goes bad in the water pump, it stops working properly and your car will begin to overheat. You can replace the water pump in just a couple of hours with some basic tools right in your own driveway. Failure to replace the water pump when it becomes a problem will cause serious damage to your engine, including blown head gaskets.

Instructions

1

Disconnect the negative battery terminal.

2

Drain the engine coolant into a proper container. You can use the coolant again if you keep it clean.

3

Remove the distributor cap and rotor by unsnapping the clips on the distributor cap. Also remove the rotor adapter, dust shield and the distributor housing.

4

Remove the engine cooling fan using the proper wrench and the fan removal tool. Remove the coupling nut, turning it counterclockwise to remove.

5

Remove the belt and pulley using the proper wrench.

6

Remove the rubber guard and the upper timing belt cover using the proper wrench.

7

Compress the timing tensioner spring using the timing belt tensioner clamp.

8

Remove the water hoses and the three bolts that mount the water pump to the engine.

9

Clean the surface of the engine where the water pump mounts with the scraping tool and make sure there is no residual gasket material left behind.

10

Place the new water pump gasket on the mounting surface and put the new water pump into place. Tighten the bolts snugly.

11

Connect the water hoses back to their proper locations.

12

Release the tensioner clamp and reinstall the timing belt cover. Tighten the bolts snugly but don't damage the threads.

13

Reinstall the fan using the proper wrench and the fan tool. Reinstall the distributor housing and dust shield.

14

Tighten the rotor adapter using the proper wrench.

15

Reinstall the rotor, O-ring and distributor cap.

16

Add the coolant to the engine and reconnect the negative battery terminal.

17

Start the engine and check thoroughly for leaks in the cooling system.