Have you ever been sitting around the house and thought, “I bet this idea would work,” only to become succumbed by reality? Maybe your thought would work, but it didn’t make sense compared to a tried and true approach after considering the amount of money, time, and effort involved. Well, leave it to Cleetus McFarland (AKA Garret Mitchell) to come up with the idea that some would love to try but aren’t willing to put the time and effort into it.
In this video, McFarland and crew decided to use Flex Seal in place of a blown head gasket on their nitrous huffing blazer. As you can imagine, while Flex Seal might fix many things, a blown head gasket is not on the list. However, the company claims Flex Seal can be used on aluminum and auto repairs. So would this outlandish idea actually work? Probably not, but like you, we wanted to see what would happen.
After McFarland inquires with Lowes employees about the best product to use, he decides on the original Flex Seal spray before checking out. And while this product is rated from -80 to 350 degrees, which sounds promising, we found out that the company’s website also states, “Flex Seal is not made to withstand extreme heat or pressure.” Meaning that this product was more than likely to fail gloriously.
Armed with 16 cans of Flex Seal, McFarland and Geroge headed back to the shop. Upon arrival, the team does a test run on a blown-up LS engine before applying the product to the engine in the Blazer. But, the guys decided to ditch the head gasket altogether and then coat the engine block mating surface and the cylinder head with Flex Seal before bolting the hurt LS back together.
George fires up the Blazer with the Flex Sealed engine reassembled. And while it does start and run, the Blazer has some hellacious valvetrain noise and didn’t seem to idle very well. But, this unit was running and surprisingly not leaking any water yet. So, the guys decided to pull the Blazer out into the parking lot and make a fist gear hit off the trans brake. Much to our surprise, the Flex Seal did its job and sealed off the water passages.
Unfortunately, the guys wouldn’t be as lucky on round two as they decided to hit the nitrous, which resulted in a small water leak. But it was the third and final nitrous hit that would seal (pun intended) the fate of the nitrous huffing blazer as the wounded LS puked water all over the engine compartment and windshield. With the nitrous still armed, George tries to restart the engine as a blowtorch-like flame emits from the throttle body, letting us know that this combination was done.
In the comment section of the video, Flex Seal left a note saying, “What will you Flex next?! For future reference, we do not recommend applying the Flex Seal Family of Products on a gasoline tank, oil tank, radiator, or on or around any other flammable liquids or ignition sources (such as Engines). Our team is always available for tips, tricks, and safety advice or visit our FAQs.”
So what did we learn from this video? First, while Flex Seal may fix many things, you can undoubtedly mark a blown LS head gasket off the list along with anything to do with gas, oil, and radiators. Secondly, if George says that you need 16 cans of Flex Seal for a project, don’t listen to him. Finally, McFarland has some off-the-wall ideas that are entertaining to watch, especially when they don’t work.