1. Locate the Belt Tensioner: The serpentine belt tensioner is usually a pulley with a lever arm. It's typically located near the alternator and may have a visible bolt head or a locking mechanism. Consult your owner's manual or a repair manual specific to your vehicle's engine for the exact location and appearance. A picture search online for "2006 Ford Expedition [4.6L or 5.4L] serpentine belt tensioner" would also be helpful.
2. Use the Correct Tool: You'll need a tool to apply pressure to the tensioner, relieving the tension on the belt. This is often a wrench or ratchet with the appropriate socket size, sometimes a special tensioner tool. Again, your owner's manual or a repair manual will specify the correct tool. Some tensioners require a short, strong push to release tension, while others have a longer arm requiring more leverage. Sometimes just a properly sized wrench can be used against the tensioner itself.
3. Loosen the Belt Tension: With the correct tool, apply pressure to the tensioner in the direction that will relieve the pressure on the belt. This will usually be counter-clockwise, but double-check this by observing the belt routing. While maintaining tension on the tensioner, carefully remove the belt from the alternator pulley and any other pulleys it wraps around.
4. Remove the Alternator: Once the belt is off, you can then proceed to remove the alternator. This involves disconnecting electrical connectors and removing mounting bolts. Again, a repair manual will provide detailed instructions and torque specifications for these steps.
Important Considerations:
* Safety First: Always disconnect the negative battery terminal before starting any work on the electrical system.
* Repair Manual: A repair manual specific to your 2006 Ford Expedition's engine (4.6L or 5.4L) is highly recommended. It will provide diagrams, torque specifications, and detailed instructions that are far safer and more accurate than general advice.
* Proper Tools: Using the incorrect tool can damage the tensioner or other components.
* Belt Routing: Pay close attention to how the belt is routed around the pulleys. Take photos or make notes before removing it to ensure correct reinstallation.
If you are not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improperly installing the belt or alternator can cause damage to your vehicle.
