Exhaust Gaskets & Seals

Is there a ticking noise from the engine bay on cold start, or a smell of exhaust fumes after a project with new headers? A leaking gasket between the exhaust manifold and cylinder head, at the turbo or in a flange joint can be the cause. In this category we bring together exhaust gaskets and seals for both car and motorcycle engines.

Three locations, three types of gaskets

Exhaust gaskets have to seal between metal parts that expand and contract with large temperature changes. The category is divided by location: exhaust manifold gaskets sit between the cylinder head and the manifold or headers, flange gaskets seal joints further down the system, and turbo gaskets sit at the turbo flanges. Brands here include Fel-Pro, Cometic Gasket, Vertex Pistons, Magnaflow and JBA.

How to choose an exhaust gasket

Start by choosing based on engine and location, then look at:

• Shape and port size: the gasket must match the ports; with ported heads or aftermarket headers, a matching gasket is typically required.
• Material: e.g. multi-layer steel (MLS) or copper. The choice depends on the surfaces, the temperature and whether the joint will be taken apart again.
• Thickness: some gaskets are available in specific thicknesses, e.g. .064 inch, which affects how the gasket compresses.
• Flange and pipe diameter: the number of bolt holes and the diameter must match, e.g. a 3-bolt flange or a donut gasket for a ball-joint connection.
• Pair or set: for engines with two cylinder banks, many gaskets are available as a pair or a complete set.

Installation and common mistakes

A new gasket only seals if the flanges are flat and clean. Remove old residue without scratching the surface, check the flanges for warping, and tighten the bolts evenly and in stages to the manufacturer's torque spec. Some joints need re-torquing after the first heat cycles – follow the instructions for the specific product. If the rest of the engine needs sealing too, you'll find it under engine gaskets and seals in the main category for gaskets and seals.

Frequently asked questions

Can I reuse an exhaust gasket?

It is typically not recommended. Most gaskets compress and conform to the flanges on first heat-up, so a used gasket rarely seals as well again. If you replace the manifold, headers or turbo, you should as a rule replace the gaskets too.

How do I spot a leaking manifold gasket?

Typical signs are a ticking noise that can be most noticeable on cold start, soot around the joint or a smell of exhaust fumes in the engine bay. A cracked manifold or loose bolts can cause the same symptoms, so check those as well.

Can a leaking exhaust cause problems at the vehicle inspection?

A leaking exhaust can lead to a remark at the vehicle inspection, and exhaust fumes can get into the cabin. Whether aftermarket parts are road legal depends on the product and the car and must be checked for the specific part number.

Should the gasket be installed with sealant?

It depends on the gasket. Many ready-made exhaust gaskets are designed to be installed dry, and extra sealant can in some cases impair the seal. Follow the manufacturer's instructions for the exact gasket you are installing.