Cars Simplified: Everything Automotive Explained

Gaskets

Gaskets are found in the space between many components in a vehicle which need that gap sealed. Many materials, especially dissimilar metals, don't seal well on their own, and gaskets are used to fix this problem. They are often made out of moderately soft materials which can withstand a large amount of heat and pressure, as well as some flexing. Gaskets are generally there to seal environments so fluids don't get in or out, but also allow two pieces to fasten together without small imperfections ruining the fitment.

Gasket Material Selection

Many different gasket materials are used throughout a vehicle and will be selected based on what the physical and chemical demands are. For example, anything used within a fuel tank needs to be fuel and solvent resistant, and anything in the engine lubrication system needs to be oil resistance.

Cork Gaskets

Cork provides high compressibility and flexibility. Combining cork with rubber produces a gasket material that is also resistant to some fuels, oils, and solvents. Cork gaskets are still available but were more common on older vehicles.

Rubber Gaskets

Rubber gaskets are quite common, but some other materials may be incorrectly identified as rubber due to their similar appearance and flexibility. Rubber can also be formulated in multiple ways.

Closed-cell sponge rubber features cells that are fully separated from surrounding cells to prevent the intrusion of most fluids. It can be found in various densities, depending on application needs.

Open-cell sponge rubber features interconnected cells that allow liquids, gasses, and other media to pass through the material. It is also available in various densities, but isn't frequently used on vehicles.

Felt Gaskets

Felt is a wool-based material formed by subjecting it to moisture, heat, and pressure. It isn't frequently use, but sometimes makes an appearance as an oil drain plug material.

Gasket Makers

In this video uploaded to YouTube by , discusses the varieties of gasket makers available. This video was published on December 1st, 2016.

Sometimes when a component needs a gasket but a form-cut gasket isn't available, or there is a custom part which no one would make a gasket for, gasket makers are used. There are a wide variety of gasket makers available, including oil resistant, high temperature, coolant resistant, copper-infused, rigid/high torque, and some that don't solidify.

Choosing the right gasket maker for the particular part connection. In some situations, a formed gasket can work better than a pre-molded gasket, while in other situations, such as when replacing head gaskets, no gasket maker can handle the stresses.

Further reading: More About Gasket Makers

Gasket Sealers

Gasket sealers are glue-like chemicals that help gaskets bond to the surface of parts. Three common types of sealants are hardening, which dries to form a solid seal, non-hardening, which doesn't dry but sticks in place, and tacky, a middle ground which assists with some gasket installations where it helps to have a gasket held in place while a part is installed.

Some gaskets are meant to be used without sealant, and some sealants make reusable gaskets one-time-use gaskets. Always check the gasket instructions for warnings.