Safety First:
* Disconnect the battery's negative terminal. This prevents accidental shorts and electrical hazards.
* Wear safety glasses and gloves. Exhaust manifolds get incredibly hot, and broken parts can cause injuries.
* Work in a well-ventilated area. Exhaust fumes are toxic.
* Support the vehicle securely. Use jack stands, never rely solely on a jack.
Tools You'll Need:
* Socket set (metric): You'll need various sizes, likely including 13mm, 15mm, and possibly others.
* Wrench set (metric): Open-end and box-end wrenches will be useful in tight spots.
* Ratchet and extensions: To reach those hard-to-access bolts.
* Breaker bar: For stubborn bolts.
* Penetrating oil (PB Blaster, etc.): Soak the bolts liberally several hours (or even overnight) *before* you start. This is crucial.
* Pry bar: To help separate the manifold from the cylinder head. Use carefully to avoid damage.
* Hammer (optional): Gentle taps might help loosen stubborn bolts.
* Torque wrench: For proper reassembly.
* Jack stands: To safely support the vehicle.
* Shop rags: To clean up the mess.
Procedure:
1. Preparation: Spray all the manifold bolts liberally with penetrating oil. Let it soak for several hours, ideally overnight. This is the most important step to avoid broken bolts.
2. Disconnect Exhaust System: Disconnect the exhaust pipe from the manifold. This usually involves bolts and possibly a gasket.
3. Remove the Manifold Bolts: Carefully remove the manifold bolts. They are usually located on top and on the sides of the manifold. They will likely be very tight and rusted. Use your breaker bar and patience. If a bolt breaks, you'll have a much bigger problem. Consider using a heat gun to help loosen the bolts (but be careful not to overheat anything).
4. Separate the Manifold: Once all the bolts are removed, the manifold should be relatively free, but it might be stuck due to rust and corrosion. Gently pry the manifold away from the cylinder head using your pry bar. Work carefully to avoid damage to the cylinder head gasket.
5. Clean the Surface: Once the manifold is removed, clean the mating surfaces of the cylinder head and the manifold thoroughly. This will help ensure a good seal when you install the new manifold.
Reassembly:
Reassembly is the reverse of removal. Use new gaskets. Torque the bolts to the manufacturer's specifications (find this in a repair manual).
Important Considerations:
* Repair Manual: A Haynes or Chilton repair manual specific to your vehicle is invaluable. It will show you exactly where all the bolts are located and provide torque specifications.
* Broken Bolts: If a bolt breaks off, you might need to drill it out and use an extractor. This is a more advanced repair.
* Exhaust Gaskets: Always replace the exhaust manifold gaskets. Reusing old gaskets will likely lead to leaks.
* Professional Help: If you're uncomfortable with any part of this process, consider taking your vehicle to a mechanic. This is a potentially complex job, especially if bolts are rusted or broken.
This process is a general guideline. Always consult a repair manual for your specific vehicle for detailed instructions and torque specifications. Remember safety is paramount.
