Why you should never reuse a cylinder head gasket – Jalopnik

A cylinder head gasket forms a seal to prevent leaks between your engine’s cylinder head and the engine block. It must accommodate the enormous pressure created by the combustion cycle and seal the connection well enough to prevent engine oil and coolant from seeping outside their respective passageways. As a general rule, gaskets are one of the car parts you should never skimp on. However, with a set of high-quality head gaskets for a regular V8 engine usually costing upwards of $100 – and some prices for head gaskets going above $1,000 – it is sometimes difficult to justify the cost for such an everyday part.

As the cost of rebuilding an engine increases, it becomes easier to justify reusing a head gasket that still looks like it has some life left in it. However, it is not a good way to keep costs down. Dragzine sums up the situation nicely, saying that “if a head gasket becomes damaged, all kinds of bad things will quickly happen that will damage the engine and the owner’s wallet.”

While it is seemingly preferable to reuse a head gasket in some situations, a new one is almost always the right choice. Even if a used head gasket looks pristine, after use it loses its ability to fill any irregularities between the head and the block. Confusion surrounding this issue likely stems from reusing a head gasket after it has been installed to check for clearance, or from the practice of reusing a gasket on a race car on the track.

Depending on the make and model of your car’s engine, there are different materials from which the head gasket can be made. As mentioned earlier, the head gasket fills the space between the cylinder head and the engine block. If this fails, your car may show some symptoms, such as white sludge under the oil cap or white smoke coming from your exhaust.

Gasket manufacturers produce multi-layer steel (MLS) head gaskets using a variety of materials, including different grades of steel and coatings. Some of these MLS gaskets use specialized layers to limit compression around the combustion chamber as they are installed, improving reliability. Dobsonian gasketsbased in Great Britain, says that “the best material for a head gasket often depends on the specific requirements of the engine.” This company primarily produces head gaskets made from MLS, graphite, copper and composites that may contain combinations of graphite, asbestos or aramid fibers. You can even get custom gaskets for your classic car, so you don’t have to rely on an old one anymore.