How to Change an Automobile Water Pump

An automobile's water pump is responsible for distributing the antifreeze within the radiator throughout the engine. A properly operating water pump is vital to keeping the engine cool. An engine can quickly overheat once a water pump no longer works efficiently. This is particularly problematic if the automobile is operated in a hot climate or in an area at high elevations. If the engine overheats, gaskets within the engine will fail and require replacement. In extreme cases, the engine block itself can crack. Thankfully, a water pump is comparatively inexpensive to purchase and installation is fairly straightforward.

Things You'll Need

• Flathead screwdriver Flair nut wrench Wrench Gasket scraper New water pump gasket Gasket sealer Antifreeze Water

Instructions

1. Drain the radiator when the engine is cool. To drain the radiator, first remove the radiator cap, then turn the drain located at the bottom of the radiator in a counterclockwise direction.

2. Remove both the upper and lower radiator hoses and the two transmission cooler lines from the radiator. The hoses are held into place with hose clamps, which can be loosened with a flathead screwdriver. Once the clamps are loosened, pull the hoses away from the radiator to disconnect them. The two transmission cooler lines are located at the bottom of the radiator and should be removed with a flair nut wrench.

3. Remove the radiator and the fan shroud. The fan shroud attaches to the back of the radiator with several small bolts around the sides of the shroud. Remove the bolts with a wrench. Then push the shroud away from the radiator. Remove the radiator by first removing the bolts which hold the radiator to the engine compartment. There is generally one bolt on each corner of the radiator. Once the bolts have been removed, lift the radiator out of the engine compartment.

4. Remove the drive belts for the alternator and the power steering, air conditioning and smog pump (if so equipped). Each of the these items is attached to the engine with brackets. To remove the drive belts, loosen the bolts on each bracket with a wrench to allow the particular devise to slide toward the engine.

5. Remove the fan assembly from the front of the water pump. The fan assembly is generally attached to the water pump with four long bolts, which can be removed with a wrench. Once the bolts have been removed, pull the fan assembly up and away from the engine.

6. Disconnect the lower radiator hose and the heater hose from the bottom of the water pump. To disconnect these hoses, use a flathead screwdriver to loosen the hose clamps. Then pull the hoses away from the water pump.

7. Remove the water pump from the engine. The water pump is attached to the engine with several bolts of varying sizes and lengths. Take note of each bolt's location on the front of the water pump to ease the installation of the replacement pump.

8. Clean any gasket material from the water pump's mounting surface on the engine with a gasket scraper. Apply gasket sealer on both sides of a new water pump gasket. Then position the gasket onto the back of the water pump.

9. Position the water pump onto the water pump's mating surface on the front of the engine. Then install and tighten each of the water pump's bolts with a wrench.

10. Install the lower radiator hose and the heater hose to the bottom of the water pump by sliding each hose over the pump. Then tighten the hose clamps with a flathead screwdriver.

11. Install the fan assembly onto the front of the water pump by inserting the bolt's through the assembly into the water pump. Tighten the bolts with a wrench.

12. Slide the drive belts for each accessory identified in step 4 over the pulley on the front of the water pump. Tighten each drive belt by pulling each device away from the engine and simultaneously tightening the device's bracket bolts with a wrench.

13. Lower the radiator into place and attach it to the engine bay by tightening the radiator's bolts with a wrench. Then slide the fan shroud against the back of the radiator and install the fan shroud bolts.

14. Install the transmission cooler lines and both radiator hoses to the transmission. Use the flair nut wrench to tighten the transmission cooler lines and a flathead screwdriver to tighten each radiator hose clamp.

15. Tighten the drain at the bottom of the radiator. Fill the radiator with a 50/50 mixture of antifreeze and water. Then install the radiator cap to complete the replacement.