What kind of exhaust sealant should be used?
2 Answers
Exhaust sealant requires high-strength, crack-resistant sealant. Introduction to sealant: In automotive maintenance, sealants have unique characteristics in sealing applications. Most mating surfaces undergo varying degrees of deformation and damage after use and disassembly, increasing the difficulty of leak prevention and making the "three leaks" issue particularly prominent in the automotive repair industry. Some areas, due to their location and high pressure, have consistently high oil leakage failure rates, becoming a major challenge in quality improvement. Classification of sealants: PVC-based automotive coating sealants are divided into tintable and non-tintable types. Their primary function is to maintain the overall body sealing, isolating external moisture, dust, and smoke. Additionally, these sealants have anti-corrosion, sound insulation, and vehicle beautification effects. Tintable sealants can be used in both low-temperature and high-temperature paint baking processes, applied to visible external seams without contaminating the dried topcoat.
Exhaust sealant isn't something you can just use any ordinary glue for. I recommend using specialized high-temperature sealants, like copper-based or silicone-based varieties. The exhaust system reaches extremely high temperatures, and regular glue will simply melt, leading to leaks that can affect engine performance and even fuel consumption. From my experience, choose products that can withstand temperatures above 800°C—Permatex's high-temperature exhaust sealant is a reliable option. When applying, first thoroughly clean the surface of any oil and rust, then spread a thin, even layer and let it cure naturally for a few minutes before assembly. Never use household silicone or adhesives—they can't handle the heat, and you might end up having to repair the entire exhaust system. Also, consider the location: manifold joints require more heat-resistant sealant, while regular exhaust pipe joints are slightly less demanding. Safety first—leaking exhaust gases are toxic and could even cause a fire. Regularly inspecting the exhaust system and replacing the sealant when needed can save you a lot of money in the long run.
