Here's a general overview of the process. This is NOT a comprehensive guide and should not be considered a substitute for a proper repair manual specific to your vehicle's engine (3.4L, 3.5L, or 3.8L V6 are common in this model year). You'll need that manual for precise torque specifications and detailed instructions.
Before You Begin:
* Safety First: Disconnect the negative battery terminal before starting any work. Wear safety glasses and gloves.
* Gather Tools and Supplies: You'll need a variety of tools, including wrenches (metric), sockets, ratchets, screwdrivers (Phillips and flathead), pliers, a coolant drain pan, new coolant (the correct type for your car), new water pump, new thermostat (recommended to replace at the same time), possibly new belts and hoses depending on their condition, and a torque wrench.
* Consult a Repair Manual: A Haynes or Chilton manual specific to your 2005 Chevy Impala is crucial. These manuals provide detailed step-by-step instructions, diagrams, and torque specifications.
General Steps (Highly Simplified):
1. Drain the Coolant: Locate the coolant drain plug at the bottom of the radiator and carefully drain the coolant into a suitable container.
2. Remove Related Components: This will vary depending on your engine, but may involve removing:
* Serpentine Belt: Use a belt tensioner tool to release tension and remove the belt.
* Fan and Fan Shroud: May need to be removed for better access to the water pump.
* Pulley(s): Depending on your engine setup, you might need to remove pulleys connected to the water pump.
* Other Components: Your repair manual will guide you on any other components that need to be removed to access the water pump.
3. Remove the Water Pump: This usually involves removing bolts that secure the pump to the engine block.
4. Install the New Water Pump: Carefully install the new water pump, ensuring the gasket is properly seated. Tighten the bolts to the correct torque specification (found in your repair manual).
5. Reinstall Components: Reinstall all components removed in the previous steps, including the serpentine belt, fan and fan shroud, and pulleys.
6. Refill with Coolant: Carefully refill the cooling system with the correct type and amount of coolant, as specified in your owner's manual or repair manual.
7. Bleed the Cooling System: This is crucial to remove air pockets from the cooling system. Consult your repair manual for the correct bleeding procedure.
8. Test: Run the engine and check for leaks. Monitor the temperature gauge to ensure the engine is not overheating.
Important Considerations:
* Thermostat Replacement: It's highly recommended to replace the thermostat while you're working on the water pump, as this is relatively easy to do at the same time and prevents future problems.
* Gasket: Use a new gasket or sealant with the new water pump.
* Torque Specifications: Following the correct torque specifications is crucial to avoid damaging the engine block or the water pump.
* Coolant Type: Use the correct type of coolant recommended for your vehicle.
This is a simplified overview. You absolutely need a repair manual for your specific year and engine. The steps and procedures can vary significantly depending on your Impala's engine. If you're not comfortable performing this repair yourself, taking it to a qualified mechanic is the safest and most reliable option.
