Everything You Need to Know about Exhaust Manifolds

What Are the Exhaust Manifolds?

Exhaust manifolds are considered as the ‘leading role’ of an engine exhaust system. However, if there is an exhaust leak, it is not the first thing to be checked because the exhaust system has many parts and some are quite complex. On the other hand, the manifold is simple in design and function.

What happens when your exhaust manifold cracks?

An exhaust manifold crack is usually caused by two reasons. As you can imagine, exhaust manifolds are subject to extreme heat, so the first possible reason is the heat cycles the manifold experiences. For a long period of time, these cycles affect the manifold to the point where it cannot handle the heat anymore.black metal pipe on brown wooden table

When that happens, the material will start to weaken and may crack in certain spots. Depending on how severe the crack is, it can be spot welded. You may be able to do it yourself or you can hire a professional to make sure the job gets done well. Keep in mind that welding of cracks is only a temporary solution.

The second reason is brackets (also referred to as “hangers”) that hold the weight of the exhaust system break down. If these brackets fail, the exhaust system will be supported by the exhaust manifold instead. However, exhaust manifolds are not meant to support the exhaust system.

Aside from leaks, cracks in the manifold can also allow outside air in. When this happens, it can cause the engine to stop working. Once you spot a crack, you should get it fixed on time because if it takes too long to get repaired, you can also cause major damage to the engine like blown head gaskets and overheated heads.

If you are not sure whether your exhaust manifold is still okay or not, here are some early detection signs that your exhaust manifold is going bad:

  1. Visible Cracking

    • As discussed above, cracks can allow outside air in. This air can cause the exhaust engine to falter. So when you see a visible crack, make sure to get it fixed immediately to avoid more issues in the long run.
  2. Exhaust Odors

    • Once you’ve noticed unpleasant odors coming from the exhaust, it’s best to seek help from a professional to resolve the issue. If it goes unnoticed, exhaust fumes may cause certain dangers like respiratory problems.
  3. Excess/Unusual noise

    • This may be caused by pressure forcing air out of the crack in the manifold. Upon a cold start of the engine, noises may be heard easier.

Exhaust Manifold Replacement

If you ignore faulty exhaust manifolds, the problem will only worsen over time. It can reduce engine power, cause sputtering, and other problems. Also, you won’t be able to pass emissions testing either. So if you have a faulty manifold, it must be taken off and inspected immediately. Afterwards, it should be replaced with a new manifold. While it might be expensive to do all that, just keep in mind that an exhaust manifold is an important component to your vehicle.