🔥 Permatex 81878-12PK Ultra Copper High Heat RTV Silicone Gasket Maker, 3 oz. (Pack of 12) Review

This product failed to meet my expectations as an automotive sealant. It claims to withstand high temperatures, yet it failed to do so in my car. The sealant broke down and actually caused damage to the area I applied it. The only positive was its ease of application. Unfortunately, that doesn't make up for its lack of performance. I would not recommend this product for any automotive use.

This was the first time I made something out of silicone myself. I was a little scared but figured that a single component silicone hose couldn't be too harsh. I printed a mold for my Geeetech A20M OG hotend from Thingiverse and squeezed some of this paste onto it. After about a day (with some heating in between) the mold was ready. I've had the best results "painting" a small amount of dish soap around the shape with a brush. The cured product is flexible and has withstood many hours at…

I used Permatex as a double safety net for my new headers. I smoothed both sides of the gasket in a thin layer. My mistake the first time was not letting the Permatex cure. I jumped in the car 30 minutes after installing it and sped down the freeway. DO NOT do this, it will burn the Permatex and render it ineffective. After the pad would inevitably burst due to improper curing, I installed new pads with Permatex and this time let them dry for 24 hours. (light driving, idling). A month later I…