Can I Use JB Weld on My Exhaust? Need Some Advice!

Maintenance & Repairs
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Introduction

I’ve been dealing with a small exhaust leak in my car, and I heard that JB Weld might be a good fix. However, I’m a bit hesitant and wanted to reach out to you all for some insight.

What is JB Weld?

For those who might not be familiar, JB Weld is a popular epoxy adhesive that is often used for automotive repairs due to its incredibly strong bond and resistance to heat and chemicals when cured properly.

Current Situation

I found a small crack in my exhaust manifold and a couple of pinhole leaks in my muffler. I’d really like to avoid a costly visit to the mechanic, so I wanted to try JB Weld as a DIY fix.

Things I’m Concerned About

  1. Heat Resistance: Given that exhaust systems can get extremely hot, I’m curious about how JB Weld holds up under those conditions. What’s the maximum temperature it can withstand once cured?
  2. Longevity: Has anyone used JB Weld on their exhaust system? If so, how long did it last before needing a redo?
  3. Application Tips: Any tips on how to properly apply it? Should I clean the surface thoroughly? Are there specific methods or techniques that can improve adhesion?
  4. Potential Risks: What are the risks of using it? I’ve read mixed opinions about it failing over time and causing more damage—or even a safety hazard.

Conclusion

I would really appreciate any firsthand experiences or technical advice from those who have attempted using JB Weld on their exhaust systems. Is it a feasible solution, or do you think I should reconsider? Thanks in advance for your input!

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I’ve used JB Weld on my exhaust system with mixed results. It held up for a few months but eventually blew out. I’m curious if the environment affects its durability.

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That’s interesting! I’ve also had a temporary success with JB Weld. It seems to depend heavily on the specific exhaust material and joint type.

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I’ve seen people compare JB Weld to exhaust tape. The tape is easier to apply, but I’ve heard JB can be more durable if applied correctly. Has anyone had long-term success?

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Exactly! I tried exhaust tape once, and it didn’t last long. JB Weld seems better for cracking issues but is tricky to apply in tight spots.

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I use JB Weld for a lot of automotive repairs. It’s not perfect for exhaust, but if done correctly, it can last. Just make sure to clean the area well before application.

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Cleaning is key! After my application, I ensured the area was prepped, but I still had issues. Just curious, what kind of vehicle did you use it on?

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I wonder how JB Weld holds up against high heat. Has anyone tried it on turbo exhaust systems? I have a friend who swears by it for his project car.

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That’s a good question! I wouldn’t trust it for long-term turbo applications, but it might be fine for minor patches.

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I’ve used JB Weld in less demanding areas, and it works fine. But for exhaust systems, I think it’s a temporary fix at best. Maybe consider proper welding for longevity.

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Good point! I think it’s perfect for quick fixes. Just don’t set your expectations too high for a permanent solution.

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You all are making it sound like a gamble! Maybe I should just invest in proper repairs instead of patterning my car with JB Weld! :joy:

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Absolutely, you can use JB Weld on your exhaust! To get the best bond, make sure to clean the area thoroughly and remove any rust or old gaskets first. It’s key for a solid attachment.

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Good point! I usually use a wire brush and then some acetone to make sure the surface is clean. Don’t forget to let it dry completely.

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When applying JB Weld, consider the temperature range. It works best at ambient temperatures around 70°F-90°F. Extreme heat can affect curing times and the bond quality.

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Totally agree with williamschristopher! Also, if this exhaust part will get really hot, ensure it cures fully before running the engine—always follow the instructions for the curing time.

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This is really helpful! Does anyone have tips on how to apply JB Weld evenly? I’m worried about making it look clean.

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I usually use a small putty knife or a popsicle stick for an even application. Just work it into the cracks and smooth it out.

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Don’t forget to wear gloves! JB Weld can be messy, and it’s tough to get off skin. Learn from my experience—my hands looked like a craft project gone wrong!

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You know, some people argue that JB Weld isn’t strong enough for high-stress exhaust parts. Anyone have thoughts on alternatives?

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