How To Skip Head Gasket Hell And Seal That Engine Up Properly

If an engine is the heart of a vehicle, then gaskets are the connective tissue that keeps it all together. So in essence, even a rebuilt engine is only as reliable as the grade of the gasket seal contained within each chamber of its heart. For if it were not for these simple, yet vital components, everything would fall apart.

When it comes to crafting kick-ass gaskets, few brands come close to producing the same grade of quality that Cometic crams into each of its products.

But even the highest-grade gasket from industry-leading brands will eventually slowly start to fail. Cometic knows this. This is precisely why we had a nice little chat with Jeff Evers, the sales manager over at Cometic, with the subject of head gasket materials and design, and various failure scenarios being our preferred topic of discussion.

Cometic Gasket install

Signs of Head Gasket Failure

Signs that a head gasket may be overtaxed or have failed can show up in a few different ways. One is combustion pressure entering the cooling system. An indication of this would be coolant coming out of the overflow tank. Another potential failure would be combustion gasses leaking between cylinders.

Coolant and oil leaks from assembly errors or machining mistakes are also a possibility. For example, a less-than-ideal surface finish could cause a leak. Heavy resurfacing of the head or block could cause the gasket to not be fully compressed, even when properly torqued, due to the dowels suddenly being too long.

Cometic Gasket Engine

Additionally, certain interfaces are tougher to seal due to the number of fasteners or OE casting design. That’s why it is so imperative that in performance applications, a high-quality set of aftermarket bolts or studs are implemented everywhere you turn a wrench. These simple yet effective additions can go a long way to ensuring a robust seal.

The last, but perhaps most frustrating-to-fix variable is detonation. The wrong air/fuel ratio, or having crappy ignition timing due to a mechanical or tuning issue can wreak havoc on any engine. That is why it is so critical to not only focus on performance but engine longevity as well. Not only for that head gasket sandwiched inside but for every other engine component stuffed inside your ride’s ticker.

A close-up look at a couple of renderings of Cometic's MLS Head Gasket designs.

MLS Head Gaskets

Cometic’s Multi-Layer Steel (MLS) gaskets are comprised of multiple embossed layers of both coated and uncoated stainless steel. This design and material selection requires less fastener clamp load, creating less bore distortion, and conforms to pressure load distribution far more evenly across the sealing area.

The embossed outer layers of Cometic’s head gaskets don’t just meet the demands of a variety of harsh sealing environments, load conditions, and surface finishes. They create an active combustion seal on a multitude of layers, which is its own separate write-up for another time.

MLX head gaskets from Cometic provide an additional layer of protection and sealing power for higher horsepower applications, race engines, and torque-rich towing vehicles.

MLX Head Gaskets

Then there is Cometic MLX Gasket (Multi-Layer-Steel-Stopper) from Cometic. This unique formula features an extra “stopper” layer for more sensitive scenarios. Utilizing a fold-over layer, this gasket forms a torque-limiting surface to help reduce the risk of combustion seal woes. An additional high-temperature polymer has been paired with specialized embossments to form a micro seal against fluids hitting the head and block surface.

Cometic Gasket StreetPro Gasket Kit

StreetPro Gasket Kits

In order to make sure you get everything you need, Cometic offers  StreetPro Kits. These package deals are intended for complete engine builds. Available for almost any popular import and domestic hotrod and race engine on the market, as well as a select few rarities, these kits feature OE or higher quality materials. These not only cover the gamut of applications, but they also make ordering dozens of gaskets and seals a hell of a lot easier. No more chasing down one part number after another and searching for obscure seals!

Cometic Gasket operations

Remember These Head Gasket Installation Basics

  • Much like human mating rituals, gasket mating requires being smooth, with a surface finish of 50 Ra or finer and full flat-deck surfaces serving as a bare minimum.
  • ALWAYS install head gaskets dry with no sealants whatsoever.
  • Follow those manufacturer torque specifications or prepare to suffer the consequences.
  • Aftermarket head bolts and studs are highly recommended for all the obvious reasons.
Cometic Head Gaskets

Selecting the Right Gasket Thickness

Cometic’s MLS head gaskets are commonly produced in thicknesses ranging anywhere from  .027 inch to .140 inch with every gasket girth imaginable being offered in between.

MLX head gaskets, on the other end, have thickness options that are based purely upon application. Furthermore, Cometic has the ability to customize gaskets as needed, so that is definitely something worth considering prior to getting that engine assembled.

Cometic Mopar Race Engine

Yeah, But What About Those Performance Ratings?

When it comes to producing monitored amounts of power, Cometic says that is on you to figure out.

In fact, Cometic doesn’t even rate its head gaskets for horsepower or boost levels, due to the unfathomable amount of variations that occur from build to build. Things such as head and deck thicknesses, fastener forms, surface finish, and intended compression ratios all play a part in how much horsepower each gasket can handle.

That being said, Cometic’s standard MLS head gasket remains the brand’s biggest seller and is a crowd favorite for those pumping out high-horsepower heartbeats.

However, even then, certain applications require even more sealing security, which is precisely why Cometic engineered its MLX line of stopper-layer head gaskets. Extreme horsepower and hard-to-seal engines demand superior gasket solutions, which means that Cometic’s R&D team won’t be letting up anytime soon.

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About the author

Micah Wright

Raised on LEGOs by grandfathers who insisted on fixing everything themselves, Micah has been a petrolhead in training since age four. His favorite past times include craft beer, strong cigars, fast cars, and culinary creativity in all of its forms.
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