Water Pump Replacement

Replacing a Water Pump
How to Replace a Water Pump

A water pump is a critical part of your car's engine cooling system. Most waters pumps fail in one of two ways, either the input shaft seal fails allowing coolant to leak externally or the main shaft bearing fails allowing the main pump pulley to wobble and make a squeaking or grinding noise. Once the water pump has failed it must be replaced or permanent engine damage could occur. Here is a list of the tools needed to complete this job in most cases. Before we start make sure the car's engine is cold and the car is located on level ground with the parking brake set, also make sure you are wearing protective gloves, eyewear and clothing.

Tools Needed to Complete this Job

1. Hose clamp pliers

2. Set of wrenches

3. Set of socket wrenches and extensions

4. Gasket scraper or cleaner

5. Shop towels

6. Gasket sealer

7. Coolant catch pan

8. Leverage Bar

Parts needed:

1. Water pump

2. Water pump gasket (usually is included with the pump)

3. Engine coolant

4. Gasket sealer

Related Replacement Parts

1. Upper and lower radiator hoses

2. Thermostat

3. Serpentine drive belt

4. Bypass hose


Step 1 - First release the hood latch cable located under the dash on the drivers side on most cars, then disconnect the negative terminal from the battery. Note: radio presets will be lost. So make a note of them to re-enter them after the job is complete.

Step 2 - Next, raise the car to gain access to the underside of the car. Always lift the vehicle according to the vehicle's manufacturers instructions. Use jack stands to secure the automobile.

Step 3 - Remove plastic covers under the engine compartment to gain access to the radiator drain valve or lower radiator hose. Position a coolant drain pan under the radiator to catch the engine coolant. Loosen the drain valve or lower radiator hose the release the coolant. Once this process is complete move to the topside of the engine compartment.

Step 4 - Remove any plastic covers and shields to gain access to the main pulley to water pump bolts. Loosen these bolts two turns but do not remove them. Next remove the serpentine drive belt. On some models you may need to remove the upper radiator hose and brackets to gain access.

Step 5 - Now, remove any obstructing brackets or accessories needed to remove the water pump mounting bolts. Remove the water pump mounting bolts. Use the leverage bar and carefully pry up on the snout of the pump, this will break the gasket seal and allow the pump to be removed.

Step 6 - Once the pump has been removed use the gasket cleaner to remove any excessive gasket material or old sealer. The gasket sealing surface needs to be as clean as possible to ensure a good seal for the new water pump gasket.

Step 7 - Before installing the new water pump match the old part to the new part, make sure the bolt holes and mounting flanges are exactly the same. Once confirmed that in fact we do have the right part install the water pump gasket. Some water pumps require gasket sealer while others do not. Typically water pump that uses an "o" ring seal do not need gasket sealer.

Step 8 - Next, reinstall the water pump and hold it in place by installing one or two mounting bolts tightened by hand. Next, install the remainder of the mounting bolts, Tighten the mounting bolts evenly and to the recommended torque tightness.

Step 9 - Once the new pump is on and secured reinstall all mounting brackets and hoses.

Step 10 - Reinstall the main cooling fan clutch or water pump drive pulley.

Step 11 - Install fan shroud and plastic valances as needed.

Step 12 - Now reinstall the serpentine belt, make sure the belt is aligned with the pulley groves.

Step 13 - Reinstall the upper radiator hose and double check all bolts and cooling hose connections.

Step 14 - Remove the radiator cap and pour the recommended coolant mixture until full.

Step 15 - Start the engine and allow to idle, Keep adding coolant as needed until the engine is running at operating temperature. You will know the engine is at operating temperature because you will able to notice coolant moving inside the radiator and the radiator will get hot. You can also reference the engine temperature gauge. Reinstall the radiator cap and check the level of the coolant reservoir, add if needed. Also after the engine has been running for a few hours allow the engine to cool completely and recheck the engine coolant level.

Best Practices

  • Once the job is done to inspect the under carriage for leaks and the engine compartment for funny noises to ensue the job it done correctly.
  • Flush radiator and cooling system while the water pump is has been removed form the engine.
  • Test the engine cooling thermostat and replace if needed.
  • Refill cooling system with new antifreeze.
  • When removing the serpentine belt inspect the condition of the belt and replace if needed
  • Check and replace the radiator hoses from the engine to the radiator
If further assistance is needed, our certified car repair technicians are ready to answer your car questions. Also, gain manufacturer specific instructions and information by clicking - Auto Repair Manual

Related Car Repair Information

To check your water pump condition, make sure the engine is off, next grab a hold of water pump flange and try to move it back and forth. There should be little to no play in the main shaft bearing. If excessive play exists the water pump has failed and needs replacement. Checking Water Pump Inspecting your water pump is another small thing that can save you big down the road. If the accessory drive belt drives your pump then you have it a lot easier. Look down the pulley for mis-alignment; this can be an indicator that the bearing is going out, letting the pulley move under the belts tension. Most water pumps have what is called a “Weep” hole; the weep hole lets coolant out that is making it into the bearing area of the pump, thus creating a leak that can be seen on the ground. If the pump is driven by the timing belt or timing chain, then inspection can be a lot tougher. Look for dried fluid under the pump area as well as fresh fluid. Water pumps can be tricky; sometimes they will only leak if the engine is running, so when the fluid leaks out it either dries on the engine or is blown away by the air circulating under the vehicle.

Article first published (Updated 2013-10-01)