Here's a general outline of the process:
1. Preparation:
* Safety First: Disconnect the negative battery terminal. This is crucial to prevent electrical shocks and short circuits.
* Gather Tools: You'll need a variety of tools, likely including:
* Socket wrench set (metric)
* Ratchet and extensions
* Wrenches (metric)
* Pliers
* Screwdrivers (possibly Phillips and flathead)
* Jack and jack stands (essential for safety)
* Wheel chocks
* New alternator (ensure you get the correct one for your Expedition's engine)
* Battery charger (optional, but recommended to prevent electrical issues after disconnecting the battery)
* Consult your repair manual: This step is critical. The manual will have precise diagrams and torque specifications specific to your vehicle's year and engine.
2. Accessing the Alternator:
* Location: The alternator is usually located on the engine's front, typically near the belt system. Consult your repair manual to verify the precise location on your specific Expedition.
* Raising the Vehicle: Safely jack up the front of the Expedition and secure it on jack stands. Never work under a vehicle supported only by a jack.
* Removing Obstacles: You might need to remove some components to access the alternator. This could include:
* Removing the serpentine belt (this usually involves loosening a tensioner pulley. Be careful; these pulleys can spring back forcefully).
* Removing various covers or brackets. Again, your repair manual is essential here.
3. Removing the Old Alternator:
* Disconnect Electrical Connections: Carefully disconnect the alternator's electrical connectors. Take note of how they are connected for easy reassembly. Some connectors may require a small amount of force to disconnect, but avoid excessive force to prevent damage.
* Remove Mounting Bolts: Loosen and remove the bolts holding the alternator to the engine. The number and location of these bolts will vary depending on the specific Expedition model.
* Remove the Alternator: Carefully remove the old alternator. It might be heavy, so be prepared.
4. Installing the New Alternator:
* Install in Reverse Order: Install the new alternator in the reverse order of removal.
* Connect Electrical Connections: Reconnect the electrical connectors.
* Tighten Bolts: Tighten the mounting bolts to the manufacturer's specified torque (find this in your repair manual).
* Install Serpentine Belt: Carefully reinstall the serpentine belt. Ensure it's properly routed over all the pulleys.
5. Final Steps:
* Lower the Vehicle: Carefully lower the Expedition from the jack stands.
* Reconnect Battery: Reconnect the negative battery terminal.
* Test the System: Start the engine and check the charging system. The alternator should be charging the battery (check the voltage with a multimeter).
Important Considerations:
* Serpentine Belt Tension: Incorrect serpentine belt tension can cause premature wear and damage to the alternator and other components. Consult your repair manual for the correct tension. A tension gauge is often helpful.
* Torque Specifications: Using the correct torque values is crucial to prevent damage. Always refer to your repair manual.
* Professional Help: If you're not comfortable with this repair, take your vehicle to a qualified mechanic. Improperly installing the alternator can cause significant damage.
Remember, this is a general guide. Your 1999 Ford Expedition's specific procedure might differ slightly. Always consult your repair manual for detailed, vehicle-specific instructions. Ignoring this advice could lead to damage to your vehicle or personal injury.
