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Will Brake Fluid Eat JB Weld?  

Will Brake Fluid Eat JB Weld

Brake fluid is some pretty caustic stuff, which is why you have to be so careful with how you repair brake lines or brake components that have begun to leak.

JB Weld – a fantastic epoxy product that can fix almost anything – is commonly used in automotive repair. It’s foolishly strong, creates a permanent bond, and can be shaped and molded, filed and sanded, and even drilled after it has had time to cure.

At the same time, using JB weld on your brake lines (especially when it’s going to come in direct contact with brake fluid) is not a smart idea. Will brake fluid eat JB Weld? No, brake fluid won’t eat JB Weld. But it will mess with the finished result and you’ll end up with “soft brakes” that are going to misbehave – if not fail outright – if this is the fixed you shoot for.

Will Brake Fluid Eat JB Weld?

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While JB Weld is a very powerful epoxy, and a frequent “go to” solution in automotive repair, the last place you want to think about using JB Weld is on your brake lines or any other part of your car’s braking system.

While the brake fluid – a super caustic, corrosive fluid that can melt through pretty much anything – isn’t going to burn holes in your JB Weld the way it might with other products, it’s still going to soften the epoxy significantly.

Instead of ending up with a bunch of other leaks you’ll end up with JB Weld that feels sort of rubbery in your hands, compromising the effectiveness of the brake system from top to bottom.

To check the current price and availability of JB Weld, click here to view the listing on Amazon.

What Glue is Resistant to Brake Fluid?

Though there are some adhesives and glues that can stand up to brake fluid (specifically glues like cataloy and ardalite), it’s not recommended to use glues or epoxy products to fix issues that are causing brake fluid to leak in the first place.

Even the best adhesives will eventually give way, falling apart even if they been able to create an otherwise permanent bond to your brake components simply because of the sheer amount of force the brake fluid has behind it – as well as the amount of vibrations those adhesives are going to be subjected to on a moving vehicle.

No, it’s best to move forward with a non-glue or adhesive solution when you’re looking to fix brakes that aren’t behaving the way you expect them to.

Can You Patch a Leaky Brake Line?

Patches can work in a pinch to seal off a leaky brake line but they should not be considered a permanent or even semipermanent solution.

Almost every auto parts store under the sun will sell a hydraulic system or braking system adhesive patch that you can use for at least 25 to 50 miles – as long as you aren’t braking aggressively – to hold the brake line together until you can get underneath your vehicle and fix the lines permanently.

JB Weld might even work in an emergency (as we mentioned a moment ago, brake lines won’t eat through JB Weld) but you don’t want to have this on your brake lines any longer than absolutely necessary.

100% new lines need to be run ASAP!

How Do You Stop a Brake Fluid Leak?

There are a couple of things you need to focus on when it comes time to stop a brake fluid leak. Here’s a quick checklist to help you hit the ground running, getting this problem resolved just as soon as humanly possible.

Find the Leak

The first piece of the puzzle is (obviously) identifying where the leak is happening and the severity of the situation.

Pop the hood, check your brake fluid reservoir, and confirm that your fluid is actually running low. Have a look underneath your vehicle to see if you can spot any obvious signs of brake fluid leakage, too. Some newspaper or butcher paper placed underneath your parked vehicle for a couple of hours will let you know how bad the leak really is.

If you are having a tough time finding the leak consider pumping the brake pedal a couple of times to force fluid through the system. You want the car to be off (this is important) when you do this, and it doesn’t hurt to have a second set of eyes to help you spot the leak as the fluid comes pouring out.

Repair Brake Lines

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One of the most common reasons you have brake fluid leaking out is because of a pinhole (or larger) leak in your actual steel brake lines or hoses.

These hoses get exposed to some pretty rough conditions (as you can imagine) every time you drive your vehicle. On top of that, there’s a ton of pressurized fluid running through the lines all the time just waiting to spring a leak.

If you find a hole in your brake lines the entire line needs to be swapped out with brand-new lines. This is not a patch job kind of solution.

To check the current price and availability of Brake Line Repair Kits, click here to view the selection on Amazon.

Final Thoughts

At the end of the day, JB Weld isn’t going to get melted away the same way that other temporary patches or adhesive/epoxy solutions might when exposed to brake fluid – but that doesn’t mean that this is something you’ll want to slop all over your brake lines for anything more than a quick fix.

JB Weld is a great emergency patch solution for a few miles (we are talking about 50 miles maximum), and even then you have to give it plenty of time to dry, cure, and harden. It’s a good product to keep in your vehicle for other fixes but if you have sprung a brake fluid leak you’ll want to reach for something else nine times out of 10.

When you get right down to it, though, leaky brake fluid is a surefire sign that something’s gone sideways with your braking system. That requires you to diagnose the issue, repair or replace the parts completely, and not try to get away with a quick fix patch – especially when you’re talking about the only system in your vehicle that actually slows and stops you on demand.

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